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2010

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Articles 6361 - 6390 of 8625

Full-Text Articles in Physical Sciences and Mathematics

Kentucky Water Resources Research Institute Annual Technical Report Fy 2009, Kentucky Water Resources Research Institute, University Of Kentucky Jan 2010

Kentucky Water Resources Research Institute Annual Technical Report Fy 2009, Kentucky Water Resources Research Institute, University Of Kentucky

KWRRI Annual Technical Reports (USGS’s 104b Grant Program)

The 2009 Annual Technical Report for Kentucky consolidates reporting requirements of the Section 104(b) base grant award into a single document that includes: 1) a synopsis of each research project conducted with grant funds during the period, 2) citations for related publications, reports, and presentations, 3) a description of information transfer activities, 4) a summary of student support during the reporting period, and 5) notable awards and achievements during the year.

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Dipolar Ordering In Crystals Of Mn12 Ac, Dmitry A. Garanin Jan 2010

Dipolar Ordering In Crystals Of Mn12 Ac, Dmitry A. Garanin

Publications and Research

Ordering in realistic elongated box-shape crystals of the molecular magnet Mn_12 Ac is investigated with the site-resolved mean-field approximation that does not assume a uniform ordering. It is shown that ferromagnetic ordering should not occur in crystals with the aspect ratio up to 12. Instead, for the aspect ratio about 6, the inner and outer regions of the crystal order in different directions, uniformly along its length. Finding ordering temperature by extrapolating the inverse susceptibility curve does not provide a correct T_C.

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Dynamical Decompactification And Three Large Dimensions, Brian Greene, Daniel N. Kabat, Stefanos Marnerides Jan 2010

Dynamical Decompactification And Three Large Dimensions, Brian Greene, Daniel N. Kabat, Stefanos Marnerides

Publications and Research

We study string gas dynamics in the early universe and seek to realize the Brandenberger - Vafa mechanism - a goal that has eluded earlier works - that singles out three or fewer spatial dimensions as the number which grow large cosmologically. Considering wound string interactions in an impact parameter picture, we show that a strong exponential suppression in the interaction rates for d > 3 spatial dimensions reflects the classical argument that string worldsheets generically intersect in at most four spacetime dimensions. This description is appropriate in the early universe if wound strings are heavy - wrapping long cycles - …

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Core/Shell Nanoparticles As Hybrid Platforms For The Fabrication Of A Hydrogen Peroxide Biosensor, Yu-Ho Won, Doreen Aboagye, Ho Seong Jang, Andrei Jitianu, Lia A. Stanciu Jan 2010

Core/Shell Nanoparticles As Hybrid Platforms For The Fabrication Of A Hydrogen Peroxide Biosensor, Yu-Ho Won, Doreen Aboagye, Ho Seong Jang, Andrei Jitianu, Lia A. Stanciu

Publications and Research

No abstract provided.

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Extraction Experiments Using Commerciallv Available Spices, Armando M. Guidote Jr, Maricar O. Ribo-Ramos, Dante Gilbert L. De Leon Jan 2010

Extraction Experiments Using Commerciallv Available Spices, Armando M. Guidote Jr, Maricar O. Ribo-Ramos, Dante Gilbert L. De Leon

Chemistry Faculty Publications

Safe and cost-effective experiments were designed for high school students to enhance their laboratory skills and knowledge on polarity and separation of mixtures. Annatto, Spanish paprika and turmeric were extracted yielding red-orange, light red-orange and yellow color, respectively. These were combined with a blue aqueous solution made from food color resulting to green mixtures. These were all extracted with kerosene or oil/kerosene. The non-polar solutes for each mixture combined with the kerosene or oil/kerosene layer, making the polar phase blue again. Students gained a better understanding of the concepts as shown in their laboratory report and test results.

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The Construction And Analysis Of Marker Gene Libraries, S.M. Short, F. Chen, Steven Wilhelm Jan 2010

The Construction And Analysis Of Marker Gene Libraries, S.M. Short, F. Chen, Steven Wilhelm

Microbiology Publications and Other Works

Marker genes for viruses are typically amplified from aquatic samples to determine whether specific viruses are present in the sample, or to examine the diversity of a group of related viruses. In this chapter, we will provide an overview of common methods used to amplify, clone, sequence, and analyze virus marker genes, and will focus our discussion on viruses infecting algae, bacteria, and heterotrophic flagellates. Within this chapter, we endeavor to highlight critical aspects and components of these methods. To this end, instead of providing a detailed experimental protocol for each of the steps involved in examining virus marker gene …

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The Invisible Enemy, Aldemaro Romero Jr. Jan 2010

The Invisible Enemy, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

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The Adsl Router Forensics Process, Patryk Szewczyk Jan 2010

The Adsl Router Forensics Process, Patryk Szewczyk

Research outputs pre 2011

In 2010 the number of threats targeting ADSL routers is continually increasing. New and emergent threats have been developed to bypass authentication processes and obtain admin privileges directly to the device. As a result many malicious attempts are being made to alter the configuration data and make the device subsequently vulnerable. This paper discusses the non-invasive digital forensics approach into extracting evidence from ADSL routers. Specifically it validates an identified digital forensic process of acquisition. The paper then discusses how the approach may be utilised to extract configuration data ever after a device has been compromised to the point where …

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Algae And Biodiesel: Patenting Energized As Green Goes Commercial, Matthew R. Priess, Stanley P. Kowalski Jan 2010

Algae And Biodiesel: Patenting Energized As Green Goes Commercial, Matthew R. Priess, Stanley P. Kowalski

Law Faculty Scholarship

In the twenty-first century, predominant dependence on fossil fuels as energy resources will not be sustainable. Developing and commercializing green energy innovations will be an essential component of the transition to a more diversified energy economy. Algal biodiesel is one of the most promising green fuels because of its potential as a renewable and sustainable fuel source without displacing food crops. Algal biodiesel research and development are necessary early steps towards a transition to a green energy economy. The strategic use of strong patent portfolios will drive this by attracting investment, incentivizing innovation and accelerating commercialization. Whereas algal biodiesel research …

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Toward A General Approach For Rna-Templated Hierarchical Assembly Of Split-Proteins, Jennifer L. Furman, Ahmed H. Badran, Oluyomi Ajulo, Jason R. Porter, Cliff I. Stains, David J. Segal, Indraneel Ghosh Jan 2010

Toward A General Approach For Rna-Templated Hierarchical Assembly Of Split-Proteins, Jennifer L. Furman, Ahmed H. Badran, Oluyomi Ajulo, Jason R. Porter, Cliff I. Stains, David J. Segal, Indraneel Ghosh

Cliff Stains Publications

The ability to conditionally turn on a signal or induce a function in the presence of a user-defined RNA target has potential applications in medicine and synthetic biology. Although sequence-specific pumilio repeat proteins can target a limited set of ss- RNA sequences, there are no general methods for targeting ssRNA with designed proteins. As a first step toward RNA recognition, we utilized the RNA binding domain of argonaute, implicated in RNA interference, for specifically targeting generic 2-nucleotide, 3′ overhangs of any dsRNA. We tested the reassembly of a split-luciferase enzyme guided by argonaute-mediated recognition of newly generated nucleotide overhangs when …

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Alignment And Orientation Of Diatomic Molecules Induced By Polarized Electron Impact, Jack W. Maseberg, Timothy J. Gay Jan 2010

Alignment And Orientation Of Diatomic Molecules Induced By Polarized Electron Impact, Jack W. Maseberg, Timothy J. Gay

Timothy J. Gay Publications

We report measurements of linear and circular fluorescence polarizations for molecular transitions in H2, D2, and N2 induced by spin-polarized electron impact. Circular polarizations resulting from some Fulcher-α transitions in H2 and D2 are found to be significant, while the null results from nitrogen’s second positive system are consistent with an earlier measurement by the Münster group. We compare this nitrogen data to that from our previous study of nitrogen’s first negative system. Emphasis is placed on understanding the mechanisms that cause the values of circular polarization from N2 to be relatively …

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Electron-Spin-Reversal Phenomenon In Optically Pumped Rubidium, E. B. Norrgard, D. Tupa, J. M. Dreiling, Timothy J. Gay Jan 2010

Electron-Spin-Reversal Phenomenon In Optically Pumped Rubidium, E. B. Norrgard, D. Tupa, J. M. Dreiling, Timothy J. Gay

Timothy J. Gay Publications

We have studied the optical pumping of mixtures of Rb vapor and N2 buffer gas by laser light tuned to the D1 transition having a spectral width of ∼500 MHz. The Rb densities are of the order of 1013 cm−3, while the buffer-gas pressures range from 0.1 to 10 torr. As the frequency of the right-hand circularly polarized laser is varied across the D1 absorption profile, the electron spin polarization of the Rb is found to take on negative values for small negative values of pump detuning from the absorption profile center. This occurs for …

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A Fpga-Based Architecture For Led Backlight Driving, Zhaoshi Zheng Jan 2010

A Fpga-Based Architecture For Led Backlight Driving, Zhaoshi Zheng

Electronic Theses and Dissertations

In recent years, Light-emitting Diodes (LEDs) have become a promising candidate for backlighting Liquid Crystal Displays [1] (LCDs). Compared with traditional Cold Cathode Fluorescent Lamps (CCFLs) technology, LEDs offer not only better visual quality, but also improved power efficiency. However, to fully utilized LEDs' capability requires dynamic independent control of individual LEDs, which remains as a challenging topic. A FPGA-based hardware system for LED backlight control is proposed in this work. We successfully achieve dynamic adjustment of any individual LED's intensity in each of the three color channels (Red, Green and Blue), in response to a real time incoming video …

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Fast-Response Liquid Crystal Displays, Meizi Jiao Jan 2010

Fast-Response Liquid Crystal Displays, Meizi Jiao

Electronic Theses and Dissertations

After about five decades of extensive material research and device development, followed by massive investment in manufacturing technology, thin-film-transistor liquid-crystaldisplay (TFT-LCD) has finally become the dominant flat panel display technology. Nowadays, LCD performances, such as viewing angle, contrast ratio, and resolution, have reached acceptable levels. The remaining major technical challenges are response time, light efficiency, and sunlight readability. Fast response time is desired to reduce motion blur and to enable field sequential color displays using red (R), green (G), and blue (B) LEDs (light emitting diodes) without noticeable color breakup. Sequential RGB colors would eliminate the commonly used spatial color …

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Survey Of Meteorite Physical Properties Density, Porosity And Magnetic Susceptibility, Robert J. Macke Jan 2010

Survey Of Meteorite Physical Properties Density, Porosity And Magnetic Susceptibility, Robert J. Macke

Electronic Theses and Dissertations

The measurement of meteorite physical properties (i.e. density, porosity, magnetic susceptibility) supplements detailed chemical and isotopic analyses for small samples (thin sections or ~300 mg portions) by providing whole-rock data for samples massing in the tens of grams. With the advent of fast, non-destructive and non-contaminating measurement techniques including helium ideal-gas pycnometry for grain density, the Archimedean ―glass bead‖ method for bulk density and (with grain density) porosity, and the use of low-field magnetometry for magnetic susceptibility, all of which rely on compact and portable equipment, this has enabled a comprehensive survey of these physical properties for a wide variety …

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A Wearable Head-Mounted Projection Display, Ricardo F. Martins Jan 2010

A Wearable Head-Mounted Projection Display, Ricardo F. Martins

Electronic Theses and Dissertations

Conventional head-mounted projection displays (HMPDs) contain of a pair of miniature projection lenses, beamsplitters, and miniature displays mounted on the helmet, as well as a retro-reflective screen placed strategically in the environment. We have extened the HMPD technology integrating the screen into a fully mobile embodiment. Some initial efforts of demonstrating this technology has been captured followed by an investigation of the diffraction effects versus image degradation caused by integrating the retro-reflective screen within the HMPD. The key contribution of this research is the conception and development of a mobileHMPD (M-HMPD). We have included an extensive analysis of macro- and …

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Freeform Reflector Design With Extended Sources, Florian Fournier Jan 2010

Freeform Reflector Design With Extended Sources, Florian Fournier

Electronic Theses and Dissertations

Reflector design stemmed from the need to shape the light emitted by candles or lamps. Over 2,000 years ago people realized that a mirror shaped as a parabola can concentrate light, and thus significantly boosts its intensity, to the point where objects can be set afire. Nowadays many applications require an accurate control of light, such as automotive headlights, streetlights, projection displays, and medical illuminators. In all cases light emitted from a light source can be shaped into a desired target distribution with a reflective surface. Design methods for systems with rotational and translational symmetry were devised in the 1930s. …

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Real-Time Cinematic Design Of Visual Aspects In Computer-Generated Images, Juraj Obert Jan 2010

Real-Time Cinematic Design Of Visual Aspects In Computer-Generated Images, Juraj Obert

Electronic Theses and Dissertations

Creation of visually-pleasing images has always been one of the main goals of computer graphics. Two important components are necessary to achieve this goal --- artists who design visual aspects of an image (such as materials or lighting) and sophisticated algorithms that render the image. Traditionally, rendering has been of greater interest to researchers, while the design part has always been deemed as secondary. This has led to many inefficiencies, as artists, in order to create a stunning image, are often forced to resort to the traditional, creativity-baring, pipelines consisting of repeated rendering and parameter tweaking. Our work shifts the …

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Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy Jan 2010

Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy

Articles

Organic-inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, such as organically modified silanes (Ormosils) have found applications as electronic, optical and protective coatings. Such coatings possess important characteristics such as chemical stability, physical strength and scratch resistance. Further performance improvement is achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through the sol-gel process. However due to the inherent difference in the reactivity of the precursors, the hydrolysis of each precursor must be carried out separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acid or acetyl acetonate prior to hydrolysis, …

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A Categorical Semantics For Fuzzy Predicate Logic, Lawrence Stout Jan 2010

A Categorical Semantics For Fuzzy Predicate Logic, Lawrence Stout

Scholarship

The object of this study is to look at categorical approaches to many valued logic, both propositional and predicate, to see how different logical properties result from different parts of the situation. In particular, the relationship between the categorical fabric I introduced at Linz in 2004 and the Fuzzy Logics studied by Hajek (2003) [5], Esteva et al. (2003) [1], and Hajek (1998) [4], comes from restricting the kind of structures used for truth values. We see how the structure of the various kinds of algebras shows up in the categorical logic, giving a variant on natural deduction for these …

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Hybridization And Postprocessing Techniques For Mixed Eigenfunctions, Bernardo Cockburn, Jay Gopalakrishnan, F. Li, Ngoc Cuong Nguyen, Jaume Peraire Jan 2010

Hybridization And Postprocessing Techniques For Mixed Eigenfunctions, Bernardo Cockburn, Jay Gopalakrishnan, F. Li, Ngoc Cuong Nguyen, Jaume Peraire

Mathematics and Statistics Faculty Publications and Presentations

We introduce hybridization and postprocessing techniques for the Raviart–Thomas approximation of second-order elliptic eigenvalue problems. Hybridization reduces the Raviart–Thomas approximation to a condensed eigenproblem. The condensed eigenproblem is nonlinear, but smaller than the original mixed approximation. We derive multiple iterative algorithms for solving the condensed eigenproblem and examine their interrelationships and convergence rates. An element-by-element postprocessing technique to improve accuracy of computed eigenfunctions is also presented. We prove that a projection of the error in the eigenspace approximation by the mixed method (of any order) superconverges and that the postprocessed eigenfunction approximations converge faster for smooth eigenfunctions. Numerical experiments using …

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Restructuring Introductory Physics By Adapting An Active Learning Studio Model, Delena Bell Gatch Jan 2010

Restructuring Introductory Physics By Adapting An Active Learning Studio Model, Delena Bell Gatch

Department of Physics and Astronomy Faculty Publications

Despite efforts to engage students in the traditional lecture environment, faculty in Georgia Southern University’s Physics Department became dissatisfied with lecture as the primary means of instruction. During the fall semester of 2006, our department began adapting the studio model to suit the needs of introductory calculus-based physics students at our institution. A studio course seamlessly integrates the lecture and laboratory courses into a single course, devoting much of the class time to active, collaborative, student-centered learning. An emphasis was placed on replacing traditional lectures with interactive, technology enriched class periods designed around the various learning styles. New teaching materials …

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Book Review: Digital Forensic Evidence Examination, Gary C. Kessler Jan 2010

Book Review: Digital Forensic Evidence Examination, Gary C. Kessler

Publications

This document is Dr. Kessler's review of the second edition of Digital Forensic Evidence Examination by Fred Cohen. ASP Press, 2010. ISBN: 978-1-878109-45-3

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Clustering Spam Domains And Destination Websites: Digital Forensics With Data Mining, Chun Wei, Alan Sprague, Gary Warner, Anthony Skjellum Jan 2010

Clustering Spam Domains And Destination Websites: Digital Forensics With Data Mining, Chun Wei, Alan Sprague, Gary Warner, Anthony Skjellum

Journal of Digital Forensics, Security and Law

Spam related cyber crimes have become a serious threat to society. Current spam research mainly aims to detect spam more effectively. We believe the identification and disruption of the supporting infrastructure used by spammers is a more effective way of stopping spam than filtering. The termination of spam hosts will greatly reduce the profit a spammer can generate and thwart his ability to send more spam. This research proposes an algorithm for clustering spam domains extracted from spam emails based on the hosting IP addresses and tracing the IP addresses over a period of time. The results show that many …

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Solid State Drives: The Beginning Of The End For Current Practice In Digital Forensic Recovery?, Graeme B. Bell, Richard Boddington Jan 2010

Solid State Drives: The Beginning Of The End For Current Practice In Digital Forensic Recovery?, Graeme B. Bell, Richard Boddington

Journal of Digital Forensics, Security and Law

Digital evidence is increasingly relied upon in computer forensic examinations and legal proceedings in the modern courtroom. The primary storage technology used for digital information has remained constant over the last two decades, in the form of the magnetic disc. Consequently, investigative, forensic, and judicial procedures are well-established for magnetic disc storage devices (Carrier, 2005). However, a paradigm shift has taken place in technology storage and complex, transistor-based devices for primary storage are now increasingly common. Most people are aware of the transition from portable magnetic floppy discs to portable USB transistor flash devices, yet the transition from magnetic hard …

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Projecting The Distribution Of Forests In New England In Response To Climate Change, Guoping Tang, Brian Beckage Jan 2010

Projecting The Distribution Of Forests In New England In Response To Climate Change, Guoping Tang, Brian Beckage

College of Agriculture and Life Sciences Faculty Publications

Aim To project the distribution of three major forest types in the northeastern USA in response to expected climate change. Location The New England region of the United States. Methods We modelled the potential distribution of boreal conifer, northern deciduous hardwood and mixed oak-hickory forests using the process-based BIOME4 vegetation model parameterized for regional forests under historic and projected future climate conditions. Projections of future climate were derived from three general circulation models forced by three global warming scenarios that span the range of likely anthropogenic greenhouse gas emissions. Results Annual temperature in New England is projected to increase by …

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Fire Effects On Demography Of The Invasive Shrub Brazilian Pepper (Schinus Terebinthifolius) In Florida Pine Savannas, Jens T. Stevens, Brian Beckage Jan 2010

Fire Effects On Demography Of The Invasive Shrub Brazilian Pepper (Schinus Terebinthifolius) In Florida Pine Savannas, Jens T. Stevens, Brian Beckage

College of Agriculture and Life Sciences Faculty Publications

Fire is a common disturbance in savanna ecosystems that may either facilitate or impede non-native plant invasions. Although fire can create recruitment opportunities for non-native plants, it can also prevent their invasion if it exerts strong negative effects on their demographic processes. Some savannas may, therefore, be able to resist invasion provided the natural, frequent-fire regime remains intact. We examined the effects of fire on the demography of the invasive shrub Brazilian pepper, Schinus terebinthifolius Raddi., which is invading fire-prone slash pine savannas of southern Florida. We studied survivorship, growth, and reproduction of low-density populations of Brazilian pepper in a …

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From Permutahedron To Aassociahedron, Colum Watt, Thomas Brady Jan 2010

From Permutahedron To Aassociahedron, Colum Watt, Thomas Brady

Articles

For each finite real reflection group $W$, we identify a copy of the type-$W$ simplicial generalised associahedron inside the corresponding simplicial permutahedron. This defines a bijection between the facets of the generalised associahedron and the elements of the type $W$ non-crossing partition lattice which is more tractable than previous such bijections. We show that the simplicial fan determined by this associahedron coincides with the Cambrian fan for $W$.

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Associative Learning In Larval Dosophila Melanogaster: The Role Of Heredity In Learning Speed And Persistence Of Leaning Into Adulthood, Jasmin Hicklen, Domonique Jones, Michelle Vieyra Jan 2010

Associative Learning In Larval Dosophila Melanogaster: The Role Of Heredity In Learning Speed And Persistence Of Leaning Into Adulthood, Jasmin Hicklen, Domonique Jones, Michelle Vieyra

Journal of the South Carolina Academy of Science

No abstract provided.

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‘Food For Life’: Looking Beyond The Horizon, Charles A. Francis, John W. Doran Jan 2010

‘Food For Life’: Looking Beyond The Horizon, Charles A. Francis, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Our real challenge appears to be anticipating what the major challenges and constraints will be to food production and distribution a decade or more into the future. This could be called ‘Beyond the Horizon’ thinking. Today there is little disagreement over the massive depletion on a global scale of two essential inputs to agriculture: fossil fuels and fresh water. We also recognize that phosphorus is found in concentrated form in only a few deposits in nature, and that agriculture is rapidly using this limited resource and dispersing it through harvested products and soil loss from fields in forms that make …

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