Enhancing the Sustainability of Integrated Biofuel Feedstock Production Systems

As use of second-generation biofuel crops increases, so do questions about sustainability, particularly their potential to affect fossil energy consumption and greenhouse gas emissions. Nitrogen (N)-fixing legumes interseeded into switchgrass (Panicum virgatum L.) may be an alternative to inorganic fertilizer in forage-feedstock systems. Research herein is divided into four general experiments: I). N replacement and feedstock impacts from legume intercrops and biochar in switchgrass; II). N-fixation rates in intercrop systems; III). impacts of biofuel systems under enhanced climate change; and, IV). projected sustainability of regional switchgrass production. Approaches included: characterization of feedstock/forage quality traits based on legume, biochar and synthetic-N applications, and harvest timing; quantification of nitrogenease activity in legumes via two techniques (15N [isotopic] enrichment and N-difference); and, determine impacts from regional switchgrass production, N-input sensitivities, and legume-intercropping via life cycle assessment (LCA). Results suggest pigeon pea, sun hemp, red clover, and partridge pea intercrops, and in some instances, biochar may supply analogous-N to that of synthetic fertilizers to Panicum species. Specifically, selected legume fixation may exceed recommended inorganic-N levels (67 kg [kilogram] N ha-1 [hectare]) in both temperate humid and semiarid tropical pasture/feedstock systems. N-difference method may be used to measure biological fixation, as it estimated comparable fixation rates to that of benchmark 15N enrichment values. Furthermore, harvest timing can be manipulated to obtain desired feedstock traits. Specifically, overwintering harvests minimized phosphorus and potassium removal, and maximize ethanol yield, hemicellulose, and in field dry-down [10.84 vs. 24.81% (P≤0.05)]. However, yield losses were observed (22%). Forage yields were generally more responsive to legumes, and legume intercropping may increase switchgrass forage quality (P-1rate. Intercropping selected legumes in switchgrass may enhance forage/feedstock quality and yield while reducing non-renewable inputs and greenhouse gas emissions

THE PORTRAYAL OF WATER AND WAVE PATTERNS IN THE MUSIC OF CLAUDE DEBUSSY

My thesis considers the shaping of Debussy’s aesthetic, the musical language he uses within an oeuvre that centres on the role of Nature as imaginative stimulus, and its particular relevance to his Water pieces within which I determine wave patterns. An examination of his piano and orchestral pieces, with particular reference to L’isle joyeuse, ‘Reflets dans l’eau’ from Images I and La mer reveals these wave patterns on every level of composition. Debussy’s use of modes to produce ‘floating’ harmonies that more easily suggest sliding curves and multiple lines above an equilibrium of water/key, together with his treatment of ‘rhythmicised time’ to evoke fluidity and the metamorphosis of spatial awareness, aid a perception of waves and liquidity within his Water music. This flowing organicism is supported by ternary-type forms when discernible (in an otherwise ‘open’ structure), and meticulous attention to musical instructions, particularly in the use of specific dynamic waves of sound, which repeatedly swell and contract. These elements contributed to the appearance of an improvisatory style that assisted the performer in the realization of Debussy’s conception for a ‘free’ music, so that the listener in turn recognizes audible waves of sound. All of these aspects are supported by the composer’s visual acuity, in the configuration and alignment of his notes and symbols on the written page, (which I have demonstrated on the relevant scores). Whether cognitively or intuitively based, they produce wave-like patterns that assist the spontaneity of Debussy’s intentions for his music, traversing bar-lines and enabling the composer to truly communicate his feelings. These pitch contours and innovative use of musical language act as signifiers for new correspondences between Debussy’s Water compositions and his twenty-first century followers, extending our knowledge of his genre

Brca2 and Trp53 deficiency cooperate in the progression of mouse prostate tumourigenesis.

Epidemiological studies have shown that one of the strongest risk factors for prostate cancer is a family history of the disease, suggesting that inherited factors play a major role in prostate cancer susceptibility. Germline mutations in BRCA2 predispose to breast and ovarian cancer with its predominant tumour suppressor function thought to be the repair of DNA double-strand breaks. BRCA2 has also been implicated in prostate cancer etiology, but it is unclear the impact that mutations in this gene have on prostate tumourigenesis. Here we have undertaken a genetic analysis in the mouse to determine the role of Brca2 in the adult prostate. We show that deletion of Brca2 specifically in prostate epithelia results in focal hyperplasia and low-grade prostate intraepithelial neoplasia (PIN) in animals over 12 months of age. Simultaneous deletion of Brca2 and the tumour suppressor Trp53 in prostate epithelia gave rise to focal hyperplasia and atypical cells at 6 months, leading to high-grade PIN in animals from 12 months. Epithelial cells in these lesions show an increase in DNA damage and have higher levels of proliferation, but also elevated apoptosis. Castration of Brca2;Trp53 mutant animals led to regression of PIN lesions, but atypical cells persisted that continued to proliferate and express nuclear androgen receptor. This study provides evidence that Brca2 can act as a tumour suppressor in the prostate, and the model we describe should prove useful in the development of new therapeutic approaches

Life cycle analysis for the cultivation and combustion of miscanthus for biofuel compared with natural gas

As negative environmental and economic impacts of fossil fuels have escalated, so has the importance of renewable bioenergy crops whose feedstocks are noncompetitive with food supplies. Compared with fossil fuels, use of lignocellulosic feedstocks offers potential for greenhouse gas reduction and highly positive net energy returns because of low input demand and high yields per unit of land area, thus making them advantageous for the emerging biofuel industry. The aim of this study was to simulate environmental impacts of producing a biofuel grass for combustion use based on the inventory of inputs and their effects on eutrophication of surface waters; acidification of land and water; photochemical ozone-creation potential (i.e. smog); global atmospheric warming; and nonrenewable resource depletion (mainly fossil fuels). Hybrid miscanthus (Miscanthus x giganteus, or giant miscanthus), a perennial C4 grass originating from East Asia, was compared with natural gas by using a life-cycle analysis model for biomass production in France. The analysis showed a trade-off between natural gas and miscanthus. The latter had a lower global-warming potential and consumed less primary nonrenewable energy but produced more emissions that promote acidification and eutrophication than did natural gas

Long-Term Sustainability Implications of Diverse Commercial Pollinator Mixtures for the Conservation Reserve Program

The persistence of Conservation Reserve Program (CRP) seed mixtures following planting is crucial for the long-term support of pollinator habitat; however, the role of disturbance regimes and their interactions in supporting this ecosystem service are largely unknown. This study set out to evaluate how ecological disturbances (prescribed burn, light disking, or fallow control) and commercially available diverse species mixtures (‘Hamilton’, ‘Bamert’, and ‘Holland’) affect pollinator habitat and the flowering period of commonly used CRP species mixtures. Specifically, three pollinator species mixtures were assessed for plant stand dynamics (plant density, yield, and dual-use pollinator-lignocellulosic feedstock potential); the resulting soil properties; and the total bloom count during the growing season. Following 5 years after their establishment, the proportions of flowering pollinator species varied by disturbance regime × seed mixture (p \u3c 0.05), with the burned Hamilton and disked Holland plots having the greatest pollinator species percentages. Overall, if the long-term stability of pollinator blooms is a key consideration for management, the Hamilton mixture should be disturbed via prescribed burning, while the Holland mixture should be disked, owing to a species-specific disturbance regime preference. However, post-senescence yield and soil health properties did not vary (p \u3e 0.05) across pollinator mixtures or disturbance regimes. Pollinator mixtures could also be harvested as a lignocellulosic feedstock without damaging pollinator habitat and providing comparable biomass for regional feedstocks; however, seeding mixtures and disturbance regimes should be considered based on desired residue usage for long-term sustainable CRP pollinator habitat

Public Preferences to CCS:How does it Change Across Countries?

AbstractThe aim of this research was to extend an Australian developed large group process which proved effective in engaging the general public on issues related to climate change, energy technologies, and the overall shift towards a low carbon society. The results from Australia, the Netherlands, Canada and Scotland found that in each of the geographic locations the context varied, and participants reported different experiences and understanding of each topic. This paper explores how context may have impacted on the results, the differences that arise and discusses the implications for policy makers and research developers

Influence of Pyrolysis Temperature and Production Conditions on Switchgrass Biochar for Use as a Soil Amendment

Biochars form recalcitrant carbon and increase water and nutrient retention in soils; however, the magnitude is contingent upon production conditions and thermo-chemical conversion processes. Herein we aim at (i) characterizing switchgrass (Panicum virgatum L.)-biochar morphology, (ii) estimating water-holding capacity under increasing ratios of char: soil; and, (iii) determining nutrient profile variation as a function of pyrolysis conversion methodologies (i.e. continuous, auger pyrolysis system versus batch pyrolysis systems) for terminal use as a soil amendment. Auger system chars produced at 600 °C had the greatest lignin portion by weight among the biochars produced from the continuous system. On the other hand, a batch pyrolysis system (400 °C – 3h) yielded biochar with 73.10% lignin (12 fold increases), indicating higher recalcitrance, whereas lower production temperatures (400 °C) yielded greater hemicellulose (i.e. greater mineralization promoting substrate). Under both pyrolysis methods, increasing biochar soil application rates resulted in linear decreases in bulk density (g cm-3). Increases in auger-char (400 °C) applications increased soil water-holding capacities; however, application rates of \u3e2 Mt ha-1 are required. Pyrolysis batch chars did not influence water-holding abilities (P\u3e0.05). Biochar macro and micronutrients increased, as the pyrolysis temperature increased in the auger system from 400 to 600 °C, and the residence time increased in the batch pyrolysis system from 1 to 3 h. Conversely, nitrogen levels tended to decrease under the two previously mentioned conditions. Consequently, not all chars are inherently equal, in that varying operation systems, residence times, and production conditions greatly affect uses as a soil amendment and overall rate of efficacy