73 research outputs found

    Linking country level food supply to global land and water use and biodiversity impacts : The case of Finland

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    The agricultural products consumed in Finland are increasingly grown on foreign farms. We analyze the Finnish imports of food and feed crops from 1986 to 2011 by products and by their geographic origin drawing a link to environmental impacts. The share of foreign crops consumed in Finland nearly doubled in the study period. The imports increased especially with commodities that could also be produced domestically. While the production of food increasingly shifted abroad, also the exports from Finland increased. >90% of the blue water of the Finnish crop supply came from foreignwater resources. Wemap the results of land and water use together with their impacts on global biodiversity, and show thatmost of the land and water use related biodiversity impacts (>93%) associated with the Finnish food consumption are related to the imports and therefore taken place outside the Finnish borders. The use ofmultiple environmental indicators can help identifying products and spatial hotspots associated with themost severe environmental impacts of the Finnish crop imports contributing to a more holistic decision-making and the promoting of sustainable food consumption both domestically and globally. (C) 2016 Elsevier B. V. All rights reserved.Peer reviewe

    The Forum: Spring 2005

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    Spring 2005 journal of the Honors Program at the University of North Dakota. The issue includes stories, poems, essays and art by undergraduate students.https://commons.und.edu/und-books/1056/thumbnail.jp

    The Forum: Spring 2004

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    Spring 2004 journal of the Honors Program at the University of North Dakota. The issue includes stories, poems, essays and art by undergraduate students.https://commons.und.edu/und-books/1054/thumbnail.jp

    A Framework for Modeling Polycyclic Aromatic Hydrocarbon Emission in Galaxy Evolution Simulations

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    We present a new methodology for simulating mid-infrared emission from polycyclic aromatic hydrocarbons (PAHs) in galaxy evolution simulations. To do this, we combine theoretical models of PAH emission features as they respond to varying interstellar radiation fields, grain size distributions, and ionization states with a new on-the-fly model for dust evolution in hydrodynamic galaxy simulations. We apply these models to 3 idealized arepo galaxy evolution simulations within the smuggle physics framework. We use these simulations to develop numerical experiments investigating the buildup of PAH masses and luminosities in galaxies in idealized analogs of the Milky Way, a dwarf galaxy, and starburst disk. Our main results follow. Galaxies with high specific star formation rates have increased feedback energy per unit mass, and are able to efficiently shatter dust grains, driving up the fraction of ultra small grains. At the same time, in our model large radiation fields per unit gas density convert aliphatic grains into aromatics. The fraction of dust grains in the form of PAHs (q_PAH) can be understood as a consequence of these processes, and in our model PAHs form primarily from interstellar processing (shattering) of larger grains rather than from the growth of smaller grains. We find that the hardness of the radiation field plays a larger role than variations in the grain size distribution in setting the total integrated PAH luminosities, though cosmological simulations are necessary to fully investigate the complex interplay of processes that drive PAH band luminosities in galaxies. Finally, we highlight feature PAH strength variations, cautioning against the usage of emission templates with constant feature strength ratios.Comment: Submitted to ApJ; comments welcom

    Higher than present global mean sea level recorded by an Early Pliocene intertidal unit in Patagonia (Argentina)

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    Reconstructions of global mean sea level from earlier warm periods in Earth?s history can helpconstrain future projections of sea level rise. Here we report on the sedimentology and age ofa geological unit in central Patagonia, Argentina, that we dated to the Early Pliocene(4.69?5.23 Ma, 2σ) with strontium isotope stratigraphy. The unit was interpreted as representativeof an intertidal environment, and its elevation was measured with differential GPS atca. 36m above present-day sea level. Considering modern tidal ranges, it was possible toconstrain paleo relative sea level within ±2.7m (1σ). We use glacial isostatic adjustmentmodels and estimates of vertical land movement to calculate that, when the Camaronesintertidal sequence was deposited, global mean sea level was 28.4 ± 11.7m (1σ) above present.This estimate matches those derived from analogous Early Pliocene sea level proxies inthe Mediterranean Sea and South Africa. Evidence from these three locations indicates thatEarly Pliocene sea level may have exceeded 20m above its present level. Such high globalmean sea level values imply an ice-free Greenland, a significant melting of West Antarctica,and a contribution of marine-based sectors of East Antarctica to global mean sea level.Fil: Rovere, Alessio. Universitat Bremen; AlemaniaFil: Pappalardo, Marta. Universidad de Pisa; ItaliaFil: Richiano, Sebastián Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; ArgentinaFil: Aguirre, Marina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Sandstrom, Michael R.. Columbia University; Estados UnidosFil: Hearty, Paul J.. University of Texas at Austin; Estados UnidosFil: Austermann, Jacqueline. Columbia University; Estados UnidosFil: Castellanos, Ignacio. Universidad Nacional de La Plata; ArgentinaFil: Raymo, Maureen E.. Columbia University; Estados Unido

    An Early Pliocene relative sea level record from Patagonia (Argentina)

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    We report ciao a geological unit surveyed and dated in central Patagonia, Argentina (Camarones town, San Jorge Gulf). The unit was interpreted as representative of an intertidal environment and dated to the Early Pliocene (4.69-5.23 Ma) with strontium isotope stratigraphy. The elevation of this unit was measured with differential GPS at ca. 36 m above present-day sea level. Considering modern tidal ranges, it was possible to constrain paleo relative sea level within ±2.5m (1s). We use glacial isostatic adjustment models and estimates of vertical land movement to calculate that, when the Camarones intertidal sequence was deposited, global mean sea level was 28.4 ± 11.7m above present. This estimate matches those derived from analogous Early Pliocene sea level proxies in the Mediterranean Sea and South Africa. Evidence from these three locations indicates that Early Pliocene sea level may have exceeded 20m above its present level. Such high global mean sea level values imply an ice-free Greenland, a significant melting of West Antarctica, and a contribution of East Antarctica to global mean sea level.Los datos utilizados para este trabajo pueden accederse haciendo clic en "Documentos relacionados".Facultad de Ciencias Naturales y Muse

    Elucidating Drivers for Variations in the Explosive Human Immunodeficiency Virus Epidemic among People Who Inject Drugs in Pakistan

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    BACKGROUND: Pakistan’s explosive human immunodeficiency virus (HIV) epidemic among people who inject drugs (PWID) varies widely across cities. We evaluated possible drivers for these variations. METHODS: Multivariable regression analyses were undertaken using data from 5 national surveys among PWID (n = 18 467; 2005–2017) to determine risk factors associated with variations in city-level HIV prevalence. A dynamic HIV model was used to estimate the population-attributable fraction (PAF; proportion of HIV infections prevented over 10 years when that risk factor is removed) of these risk factors to HIV transmission and impact on HIV incidence of reducing their prevalence. RESULTS: Regression analyses suggested that city-level HIV prevalence is strongly associated with the prevalence of using professional injectors at last injection, heroin use in last month, and injecting ≥4 times per day. Through calibrating a model to these associations, we estimate that the 10-year PAFs of using professional injectors, heroin use, and frequent injecting are 45.3% (95% uncertainty interval [UI], 4.3%–79.7%), 45.9% (95% UI, 8.1%–78.4%), and 22.2% (95% UI, 2.0%–58.4%), respectively. Reducing to lowest city-level prevalences of using professional injectors (2.8%; median 89.9% reduction), heroin use (0.9%; median 91.2% reduction), and frequent injecting (0.1%; median 91.8% reduction) in 2020 reduces overall HIV incidence by 52.7% (95% UI, 6.1%–82.0%), 53.0% (95% UI, 11.3%–80.2%), and 28.1% (95% UI, 2.7%–66.6%), respectively, over 10 years. CONCLUSIONS: Interventions should focus on these risk factors to control Pakistan’s explosive HIV epidemic among PWID, including a concomitant expansion of high-coverage needle/syringe provision, opioid substitution therapy, and antiretroviral therapy

    DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy

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    We compare 500~pc scale, resolved observations of ionised and molecular gas for the z0.02z\sim0.02 starbursting disk galaxy IRAS08339+6517, using measurements from KCWI and NOEMA. We explore the relationship of the star formation driven ionised gas outflows with colocated galaxy properties. We find a roughly linear relationship between the outflow mass flux (Σ˙out\dot{\Sigma}_{\rm out}) and star formation rate surface density (ΣSFR\Sigma_{\rm SFR}), Σ˙outΣSFR1.06±0.10\dot{\Sigma}_{\rm out}\propto\Sigma_{\rm SFR}^{1.06\pm0.10}, and a strong correlation between Σ˙out\dot{\Sigma}_{\rm out} and the gas depletion time, such that Σ˙outtdep1.1±0.06\dot{\Sigma}_{\rm out} \propto t_{dep}^{-1.1\pm0.06}. Moreover, we find these outflows are so-called ``breakout" outflows, according to the relationship between the gas fraction and disk kinematics. Assuming that ionised outflow mass scales with total outflow mass, our observations suggest that the regions of highest ΣSFR\Sigma_{\rm SFR} in IRAS08 are removing more gas via the outflow than through the conversion of gas into stars. Our results are consistent with a picture in which the outflow limits the ability for a region of a disk to maintain short depletion times. Our results underline the need for resolved observations of outflows in more galaxies.Comment: 16 pages, 7 figures, Submitted to Ap

    A Two-Component Probability Distribution Function Describes the mid-IR Emission from the Disks of Star-Forming Galaxies

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    High-resolution JWST-MIRI images of nearby spiral galaxies reveal emission with complex substructures that trace dust heated both by massive young stars and the diffuse interstellar radiation field. We present high angular (0."85) and physical resolution (20-80 pc) measurements of the probability distribution function (PDF) of mid-infrared (mid-IR) emission (7.7-21 μ\mum) from 19 nearby star-forming galaxies from the PHANGS-JWST Cycle-1 Treasury. The PDFs of mid-IR emission from the disks of all 19 galaxies consistently show two distinct components: an approximately log-normal distribution at lower intensities and a high-intensity power-law component. These two components only emerge once individual star-forming regions are resolved. Comparing with locations of HII regions identified from VLT/MUSE Hα\alpha-mapping, we infer that the power-law component arises from star-forming regions and thus primarily traces dust heated by young stars. In the continuum-dominated 21 μ\mum band, the power-law is more prominent and contains roughly half of the total flux. At 7.7-11.3 μ\mum, the power-law is suppressed by the destruction of small grains (including PAHs) close to HII regions while the log-normal component tracing the dust column in diffuse regions appears more prominent. The width and shape of the log-normal diffuse emission PDFs in galactic disks remain consistent across our sample, implying a log-normal gas column density NN(H)1021\approx10^{21}cm2^{-2} shaped by supersonic turbulence with typical (isothermal) turbulent Mach numbers 515\approx5-15. Finally, we describe how the PDFs of galactic disks are assembled from dusty HII regions and diffuse gas, and discuss how the measured PDF parameters correlate with global properties such as star-formation rate and gas surface density.Comment: 30 pages without appendix, 17 figures, (with appendix images of full sample: 56 pages, 39 figures), accepted in A

    Genetic effects on gene expression across human tissues

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    Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of diseas
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