126 research outputs found

    USDA's Livestock Gross Margin Insurance for Dairy: What Is It and How Can It Be Used for Risk Management

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    Dairy farmers are faced with tremendous and increasing volatility, both in terms of milk prices, and the costs of purchased feed. There is a new weapon in the risk management arsenal of U.S. dairy producers: the Livestock Gross Margin for Dairy (LGM-Dairy) insurance program controls for lower gross revenue, defined as the value of milk produced minus feed costs. This program is administered by USDA's Risk Management Agency, and made available via authorized crop insurance agents to dairy farm operators in the lower 48 states.

    Livestock Gross Margin Insurance for Dairy Cattle: An Analysis of Program Performance and Cost under Alternative Policy Configurations

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    Livestock Gross Margin insurance for dairy cattle (LGM-Dairy) is a risk management tool that can be used to insure a lower bound on a dairy producer’s gross margin. In this paper we (1) review the basic structure of LGM-Dairy (2) examine the sensitivity of Gross Margin Guarantee (GMG) and premium to changes in feeding regimes and (3) quantify impacts of changes in deductible level on important program characteristics.Dairy Price Risk, Uncertainty, Livestock Insurance., Agribusiness, Farm Management, Financial Economics, Livestock Production/Industries, Production Economics, Risk and Uncertainty,

    Amplifying Agroecology in Vermont: Principles and Processes to Foster Food Systems Sustainability

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    Agroecology is grounded in principles that support transitions toward economic, social and ecological sustainability and proposes that real and lasting change will require a significant transformation of our agri-food systems. Evidence for agroecology’s potential continues to grow, both through word of mouth by farmers and social movements, and through recent scientific assessments of its performance. With endorsements from the Food & Agriculture Organization of the United Nations (FAO), national governments in both the global north and south, and social movements, it is developing the web of ‘thick legitimacy’ required for even broader adoption (Montenegro de Wit & Iles, 2016). “...Agroecology represents a system that works with nature instead of against it and offers an approach to food production that boosts biodiversity, creates ecological resilience, improves soils, cools the planet and reduces energy and resource use. It has been shown to be highly productive, to provide highly diverse dietary offerings and to support the process of community building and women’s empowerment” (Anderson et al., 2020, p. 3). However, agroecology is an approach that is not yet recognized as being actively practiced in Vermont and the USA, despite its significant potential for supporting transitions to sustainable food systems in different contexts. The University of Vermont is home to researchers and practitioners at the forefront of agroecological research and learning. The objectives of this white paper are to demonstrate the importance of agroecology for the future of sustainable food systems in Vermont, and as a framework to assess and advance transformations towards sustainability. In this paper we will: a) Demonstrate the global evidence base for agroecology and the potential of agroecology in the United States, and Vermont. b) Present the case for an agroecological principles-based approach to assess food and farming sustainability which can capture the multifunctional dynamics and benefits of agroecology to economic, social and ecological sustainability. c) Present examples based on our newly developed Agroecological Assessment for Sustainability framework to existing initiatives in Vermont that represent constituencies across a range of farm types and scales. d) Demonstrate the importance of participatory and transdisciplinary approaches for researc

    Very-high energy gamma-ray astronomy: A 23-year success story in high-energy astroparticle physics

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    Very-high energy (VHE) gamma quanta contribute only a minuscule fraction - below one per million - to the flux of cosmic rays. Nevertheless, being neutral particles they are currently the best "messengers" of processes from the relativistic/ultra-relativistic Universe because they can be extrapolated back to their origin. The window of VHE gamma rays was opened only in 1989 by the Whipple collaboration, reporting the observation of TeV gamma rays from the Crab nebula. After a slow start, this new field of research is now rapidly expanding with the discovery of more than 150 VHE gamma-ray emitting sources. Progress is intimately related with the steady improvement of detectors and rapidly increasing computing power. We give an overview of the early attempts before and around 1989 and the progress after the pioneering work of the Whipple collaboration. The main focus of this article is on the development of experimental techniques for Earth-bound gamma-ray detectors; consequently, more emphasis is given to those experiments that made an initial breakthrough rather than to the successors which often had and have a similar (sometimes even higher) scientific output as the pioneering experiments. The considered energy threshold is about 30 GeV. At lower energies, observations can presently only be performed with balloon or satellite-borne detectors. Irrespective of the stormy experimental progress, the success story could not have been called a success story without a broad scientific output. Therefore we conclude this article with a summary of the scientific rationales and main results achieved over the last two decades.Comment: 45 pages, 38 figures, review prepared for EPJ-H special issue "Cosmic rays, gamma rays and neutrinos: A survey of 100 years of research

    The Problem of Experience in the Study of Organizations

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    This paper deals with the fact that we cannot experience large organizations directly, in the same way as we can experience individuals or small groups, and that this non-experientiability has certain implications for our scientific theories of organizations. Whereas a science is animated by a constructive interplay of theory concepts and experience concepts, the study of organizations has been confined to theory concepts alone. Implications of this analysis for developing a science of organizations are considered.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68303/2/10.1177_017084069301400102.pd

    Seroprevalence and distribution of arboviral infections among rural Kenyan adults: A cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Arthorpod-borne viruses (arboviruses) cause wide-spread morbidity in sub-Saharan Africa, but little research has documented the burden and distribution of these pathogens.</p> <p>Methods</p> <p>Using a population-based, cross-sectional study design, we administered a detailed questionnaire and used ELISA to test the blood of 1,141 healthy Kenyan adults from three districts for the presence of anti-viral Immunoglobulin G (IgG) antibodies to the following viruses: dengue (DENV), West Nile (WNV), yellow fever (YFV), Chikungunya (CHIKV), and Rift Valley fever (RVFV).</p> <p>Results</p> <p>Of these, 14.4% were positive for DENV, 9.5% were WNV positive, 9.2% were YFV positive, 34.0% were positive for CHIKV and 0.7% were RVFV positive. In total, 46.6% had antibodies to at least one of these arboviruses.</p> <p>Conclusions</p> <p>For all arboviruses, district of residence was strongly associated with seropositivity. Seroprevalence to YFV, DENV and WNV increased with age, while there was no correlation between age and seropositivity for CHIKV, suggesting that much of the seropositivity to CHIKV is due to sporadic epidemics. Paradoxically, literacy was associated with increased seropositivity of CHIKV and DENV.</p

    Quantitative historical analysis uncovers a single dimension of complexity that structures global variation in human social organization.

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    Do human societies from around the world exhibit similarities in the way that they are structured, and show commonalities in the ways that they have evolved? These are long-standing questions that have proven difficult to answer. To test between competing hypotheses, we constructed a massive repository of historical and archaeological information known as "Seshat: Global History Databank." We systematically coded data on 414 societies from 30 regions around the world spanning the last 10,000 years. We were able to capture information on 51 variables reflecting nine characteristics of human societies, such as social scale, economy, features of governance, and information systems. Our analyses revealed that these different characteristics show strong relationships with each other and that a single principal component captures around three-quarters of the observed variation. Furthermore, we found that different characteristics of social complexity are highly predictable across different world regions. These results suggest that key aspects of social organization are functionally related and do indeed coevolve in predictable ways. Our findings highlight the power of the sciences and humanities working together to rigorously test hypotheses about general rules that may have shaped human history

    The Occurrence of Rocky Habitable-zone Planets around Solar-like Stars from Kepler Data

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    We present the occurrence rates for rocky planets in the habitable zones (HZs) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define η⊕ as the HZ occurrence of planets with radii between 0.5 and 1.5 R⊕ orbiting stars with effective temperatures between 4800 and 6300 K. We find that η⊕ for the conservative HZ is between 0.37^(+0.48)_(−0.21) (errors reflect 68% credible intervals) and 0.60^(+0.90)_(−0.36) planets per star, while the optimistic HZ occurrence is between 0.58^(+0.73)_(−0.33) and 0.88^(+1.28)_(−0.51) planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates between using Poisson likelihood Bayesian analysis and using Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ~6 pc away and there are ~4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun

    The Occurrence of Rocky Habitable Zone Planets Around Solar-Like Stars from Kepler Data

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    We present occurrence rates for rocky planets in the habitable zones (HZ) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define η⊕\eta_\oplus as the HZ occurrence of planets with radius between 0.5 and 1.5 R⊕R_\oplus orbiting stars with effective temperatures between 4800 K and 6300 K. We find that η⊕\eta_\oplus for the conservative HZ is between 0.37−0.21+0.480.37^{+0.48}_{-0.21} (errors reflect 68\% credible intervals) and 0.60−0.36+0.900.60^{+0.90}_{-0.36} planets per star, while the optimistic HZ occurrence is between 0.58−0.33+0.730.58^{+0.73}_{-0.33} and 0.88−0.51+1.280.88^{+1.28}_{-0.51} planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates using both a Poisson likelihood Bayesian analysis and Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with 95%95\% confidence that, on average, the nearest HZ planet around G and K dwarfs is about 6 pc away, and there are about 4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun.Comment: To appear in The Astronomical Journa
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