10 research outputs found

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    Joseph Louis Lagrange. Mathematician. Biographical Sketch.

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    From the Farm to the Table: What All Americans Need to Know about Agriculture

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    As with other areas of human industry, it has been assumed that technological progress would improve all aspects of agriculture. Technology would increase both efficiency and yield, or so we thought. The directions taken by technology may have worked for a while, but the same technologies that give us an advantage also create disadvantages. Itā€™s now a common story in rural America: pesticides, fertilizers, ā€œbig ironā€ combines, and other costly advancements may increase speed but also reduce efficiency, while farmers endure debt, dangerous working conditions, and long hours to pay for the technology. Land, livelihood, and lives are lost in an effort to keep up and break even. There is more to this story that affects both the food we eat and our provisions for the future. Too many Americans eat the food on their plates with little thought to its origin and in blind faith that government regulations will protect them from danger. While many Americans might have grown up in farming families, there are fewer family-owned farms with each passing generation. Americans are becoming disconnected from understanding the sources and content of their food. The farmers interviewed in From the Farm to the Table can help reestablish that connection. Gary Holthaus illuminates the state of American agriculture today, particularly the impact of globalization, through the stories of farmers who balance traditional practices with innovative methods to meet market demands. Holthaus demonstrates how the vitality of Americaā€™s communities is bound to the successes and failures of its farmers. In From the Farm to the Table, farmers explain how their lives and communities have changed as they work to create healthy soil, healthy animals, and healthy food in a context of often inappropriate federal policy, growing competition from abroad, public misconceptions regarding government subsidies, the dangers of environmental damage and genetically modified crops, and the myths of modern economics. Rather than predicting doom and despair for small American growers, Holthaus shows their hope and the practical solutions they utilize. As these farmers tell their stories, ā€œorganicā€ and ā€œsustainableā€ farming become real and meaningful. As they share their work and their lives, they reveal how those concepts affect the food we eat and the land on which itā€™s grown, and how vital farming is to the American economy. Gary Holthaus is the author of several books, including Wide Skies: Finding a Home in the West, Circling Back, and Unexpected Manna. With much love, dedication, and diligence, and through interviews with farmers in Minnesota, Holthaus tells the story of today\u27s agriculture... it is not a pretty picture... This book serves an as eye-opener. Highly recommended. --Choice [Holthaus\u27s] book is a comprehensive look at the context of agriculture today and is valuable for urban readers as well as rural people who want to know where their food comes from and how it is produced. --Dickey County Leader Rural America is not somehow \u27behind us,\u27 a part of a past that is no longer central to our lives. For all of us, Holthaus shows, the thinking of rural people is relevant to the well-being of the nation and far more complex than we have realized. This book provides fresh insight into what is going on in the rural countryside and what farmers themselves have thought about those changes. --Donald Worster, author of Nature\u27s Economy: A History of Ecological Ideas Farmers all over the world have begun to choose a new path. --Fred Kirschenmann, Distinguished Fellow for the Leopold Center for Sustainable A His selected interviewees are all compelling studies. --Harvard Book Review Holthaus is a world-class listener, so much so that he is able to bring us farm stories that enlighten and enrich our sphere of knowledge and understanding of agriculture and all that it encompasses. --Helene Murray, Executive Director, Minnesota Institute for Sustainable Agriculture Holthaus\u27s book tells the story of modern agriculture through engaging interviews with men and women who make a living farming in southeastern Minnesota. In a tone reminiscent of Wendell Berry\u27s A Place on Earth, he examines the far-reaching effects of genetically modified organisms, free-trade agreements that nurture \u27transnational corporate profit,\u27 dependence on fossil fuel-derived chemicals, and the toll all this has taken on the land and farmers... Recommended for academic agriculture collections. --Library Journal When farmers tell their story, there is no end to learningā€¦. A solid piece of work in the mosaic of the farming history of our country. --Claus Sproll, Lilipohhttps://uknowledge.uky.edu/upk_environmental_sciences/1003/thumbnail.jp

    Knowledge, Causality and Temporal Representation

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    In this paper, a formal semantic framework is developed in order to account for the temporal semantics of text. The theory is able to represent and reason about both semantic issues, which are independent of world knowledge (wk), and pragmatic issues, which are not, within a single logical framework. The theory will allow a text's semantic entailments to differ from its pragmatic ones, even though they are all derived within the same logic. I demonstrate that this feature of the theory gives rise to solutions to several puzzles concerning the temporal structure of text. 1 The Problem The purpose of this paper is to provide a formal account of the temporal semantics of text. The chief goal is to explain when a text is temporally coherent: it should not mislead the reader as to the order of the events reported. If John hits Max, causing Max to turn round (to face John), then text (1) reflects this while (2) distorts it: (1) John hit Max. Max turned round. (2) Max turned roun..

    A processing framework for temporal analysis and its application to instructional texts

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    Temporal analysis is the task of determining the temporal structure of a given text. Such a structure represents the order of the events and states mentioned in the text on a time line. The main contribution of this thesis is in presenting a new processing framework for temporal analysis.The framework is a computational one and has been implemented in a system called taste for the temporal analysis of instructional texts. In particular, taste has been successfully tested on nine cookery recipes. Amongst the more important ideas explored in this thesis are the following: ā€¢ We integrate qualitative information (as expressed by temporal connectives like before and after) and quantitative information (as expressed in phrases like for 20 minutes and 20 minutes before) in a text into the temporal analysis framework. Previous work has only considered qualitative information but ignored the quantitative kind. ā€¢ We propose a new approach to the problem of integrating the current event or state into the preceding discourse. This problem has been identified as important for solving the temporal analysis task. ā€¢ We show how information from the environment surrounding a text can affect the temporal analysis of instructional texts. In particular, we show that different temporal structures for the same text can be derived in different environments. Note that the environment information is in addition to the usual information considered in temporal analysis such as information from tense and aspect, temporal connectives and real-world knowledge. An example of information from the environment for the domain of cookery recipes is the availability of resources for carrying out an action. ā€¢ We incorporate techniques developed in the field of temporal reasoning into the temporal analysis task. In addition, we analyse the complexity of temporal reasoning algorithm needed in the temporal analysis of instructional texts. ā€¢ We propose a novel ontology for representing the composite and repetitive events that are mentioned in cookery recipes.Finally, the thesis ends with some suggestions for extending the work reported here

    Localisation and Resilience at the local level: the case of Transition Town Totnes

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    This thesis provides a critical review of the Transition movement, a grassroots response to peak oil and climate change, co-founded by this author. It focuses on two key aspects of the Transition approach, resilience and economic relocalisation, with the aim of analysing whether and how they can be implemented in a locality based on the Transition approach, and assessing what socio-economic and community-related structures would be necessary to implement such a process. The focus of the research is Totnes, Devon, which because of its status as the UKā€™s first Transition initiative and the longer history of various initiatives to promote local resilience, offers a valuable case study of attempts to practically implement resilience and localisation. A variety of research methods were employed, including surveys, focus groups, oral history and in-depth interviews, as well less conventional public participation methods such as Open Space and World CafĆ©. The first major finding was that Transition Town Totnes (TTT) has become a significant organisation in the town, with a high level of popular support. It was also found that the obstacles to resilience and relocalisation lie not, as was hypothesised, in a lack of skills or an absence of community cohesion, but in issues of governance and the need for increased social entrepreneurship. It was found that what researchers call the ā€˜Value Action Gapā€™ (i.e. the gap between peopleā€™s declared sympathies and intentions and their actions) exists in Totnes as much as anywhere else, but that some of TTTā€™s projects, such as ā€˜Transition Togetherā€™, are working imaginatively to overcome this and to reduce emissions. From this evidence is it concluded that Transitionā€™s approach towards relocalisation and reducing carbon emissions can be argued to be effective in, generating engagement and initiating new enterprises. Like other ā€˜greenā€™ initiatives, it struggles to engage those from more disadvantaged backgrounds, but some of its initiatives are showing promise for overcoming this. Its primary contribution is in suggesting a redefining of resilience, not as a state of preparedness for disaster, but as a desired characteristic of a sustainable society. A more resilient community, it is argued, would be one more in control of its food and energy production, as well as being one that enables inward financial investment. It also argues that the government focus on ā€˜localismā€™, the devolving of political power to the local level, ought to be expanded to include ā€˜localisationā€™, the strengthening of local production to meet local needs, a shift which would financially benefit local communities. It argues that the key challenge for Transition initiatives such as TTT is going to be scaling up from being ā€˜nicheā€™ organisations to become economically viable organisations with a broad appeal and engagement, and also articulates the need for ā€˜Resilience Indicatorsā€™ which would allow communities to measure the degree to which their levels of resilience are increasing.Economic and Social Research Council

    Molecular studies of the sources and significance of archaeal lipids in the oceans

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    Thesis (Ph. D. in Geochemistry)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2013.Cataloged from PDF version of thesis.Includes bibliographical references.Marine archaea are ubiquitous and abundant in the modem oceans and have a geologic record extending >100 million years. However, factors influencing the populations of the major clades - chemolithoautotrophic Marine Group I Thaumarchaeota (MG-I) and heterotrophic Marine Group II Euryarchaeota (MG-II) - and their membrane lipid signatures are not well understood. Here, I paired techniques of organic geochemistry and molecular biology to explore the sources and significance of archaeal tetraether lipids in the marine water column. Using metagenomics, 16S rDNA pyrosequencing, QPCR and mass spectrometric analyses, I found that uncultivated MG-IL Euryarchaeota synthesize glycerol dialkyl glycerol tetraether (GDGT) lipids - including crenarchaeol, previously thought limited to autotrophic Thaumarchaeota. This finding has important implications for paleoenvironmental proxies reliant upon GDGTs. To investigate the effects of organic matter and bicarbonate + ammonia amendments on archaeal tetraether lipids and microbial community composition, I conducted large scale microcosm experiments. Experimental conditions did not promote the overall growth of archaea, but several changes in tetraether lipid abundance and relative ring distribution suggest that future incubation labeling studies using whole seawater may be valuable in probing the metabolism of individual archaeal clades in mixed populations. A rapid decrease in GDGT concentrations was observed within the first 44 h of the experiment, suggesting that the residence time of these compounds in the open ocean may be short. Changes in functional gene representation and microbial community composition over the course of the experiment provide potential insight into mechanisms of copiotrophy and the identity of bacteria that may degrade GDGTs. Finally, I present the results of a study of the sources and patterns of bacterial and archaeal GDGTs detected in the Lost City Hydrothermal Vent Field. Branched GDGTs, generally considered markers of terrestrial input to marine sediments, were detected in carbonate chimneys of this alkaline site near the mid-Atlantic Ridge. A relatively uncommon H-shaped GDGT was also present, and appears to be a marker of hydrothermal archaeal input rather than a mesophilic euryarchaeotal signal. Taken together, the work presented in this thesis emphasizes the necessity of understanding the biological underpinnings of archaeal lipids in the environment, increasingly used as biomarkers in microbial ecology and paleoenvironmental reconstruction.by Sara Ann Lincoln.Ph.D.in Geochemistr
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