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2008

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Articles 5431 - 5460 of 5871

Full-Text Articles in Physical Sciences and Mathematics

Book Review: Your Cosmic Context: An Introduction To Modern Cosmology, T. D. Oswalt Jan 2008

Book Review: Your Cosmic Context: An Introduction To Modern Cosmology, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Your Cosmic Context : an Introduction to Modern Cosmology by Todd Duncan and Craig Tyler Pearson Addison-Wesley, 2008 466p, 0132400103 $80.00, 9780132400107 $80.00.


Fact Sheet, Yale University Office Of Institutional Research Jan 2008

Fact Sheet, Yale University Office Of Institutional Research

Fact Sheets

No abstract provided.


Cold Atmospheric Pressure Air Plasma Jet For Medical Applications, Juergen Friedrich Kolb, A.-A H. Mohamed, R. O. Price, R. J. Swanson, A. Bowman, R. L. Chiavarini, Michael W. Stacey Jan 2008

Cold Atmospheric Pressure Air Plasma Jet For Medical Applications, Juergen Friedrich Kolb, A.-A H. Mohamed, R. O. Price, R. J. Swanson, A. Bowman, R. L. Chiavarini, Michael W. Stacey

Bioelectrics Publications

By flowing atmospheric pressure air through a direct current powered microhollow cathode discharge, we were able to generate a 2 cm long plasma jet. With increasing flow rate, the flow becomes turbulent and temperatures of the jet are reduced to values close to room temperature. Utilizing the jet, yeast grown on agar can be eradicated with a treatment of only a few seconds. Conversely, animal studies show no skin damage even with exposures ten times longer than needed for pathogen extermination. This cold plasma jet provides an effective mode of treatment for yeast infections of the skin.


Estimates Of Positive Solutions For Higher Order Right Focal Boundary Value Problem, Bo Yang Jan 2008

Estimates Of Positive Solutions For Higher Order Right Focal Boundary Value Problem, Bo Yang

Faculty Articles

We consider the (p;n - p) right focal boundary value problem. A new set of upper and lower estimates of positive solutions for the boundary value problem are obtained. These estimates implement and improve the ones in the literature.


Otolith Chemistry Indicates Population Structuring By The Antarctic Circumpolar Current, Julian R. Ashford, Cynthia M. Jones, Eileen E. Hofmann, Inigo Everson, Carlos A. Moreno, Guy Duhamel, Richard Williams Jan 2008

Otolith Chemistry Indicates Population Structuring By The Antarctic Circumpolar Current, Julian R. Ashford, Cynthia M. Jones, Eileen E. Hofmann, Inigo Everson, Carlos A. Moreno, Guy Duhamel, Richard Williams

CCPO Publications

Large-scale transport of seawater in ocean currents may generate spatially complex population structure through the advection of life stages of marine fish species. To test this, we compared the chemistry of otolith nuclei from Patagonian toothfish (Dissostichus eleginoides), presently managed as spatially discrete Populations corresponding to fishing management areas along the Antarctic Circumpolar Current (ACC), which transports water eastward around the Southern Ocean. The chemistry of otolith nuclei, laid down during early life, differed significantly between fishing areas Off South America and the Antarctic and between some Antarctic areas. However, we found significant discrepancies from expectation for a …


A Modelling Study Of Developmental Stage And Environmental Variability Effects On Copepod Foraging, Jerry D. Wiggert, Eileen E. Hofmann, Gustav-Adolf Paffenhöfer Jan 2008

A Modelling Study Of Developmental Stage And Environmental Variability Effects On Copepod Foraging, Jerry D. Wiggert, Eileen E. Hofmann, Gustav-Adolf Paffenhöfer

CCPO Publications

We used a stochastic Lagrangian model to study how behaviour contributes to copepod grazing success. The model simulates distinct foraging behaviours of Clausocalanus furcatus, Paracalanus aculeatus, and Oithona plumifera. Three sets of simulations were performed to investigate the effects of (a) prey-size preference; (b) variation in prey-size spectra; and (c) turbulence intensity on these species’ grazing rates. The size preference simulations demonstrate that, compared with copepodites, mature females have cell ingestion rates that are an order of magnitude lower, while carbon uptake is reduced by 35%. A prey spectrum that is skewed towards cells ,<6 >μm promotes copepodite …


Transverse Structure Of Wind-Driven Flow At The Entrance To An Estuary: Nansemond River, Diego A. Narváez, Arnoldo Valle-Levinson Jan 2008

Transverse Structure Of Wind-Driven Flow At The Entrance To An Estuary: Nansemond River, Diego A. Narváez, Arnoldo Valle-Levinson

CCPO Publications

Observations of current velocity profiles were combined with an analytical solution to study the transverse partition of the wind-driven flow in an estuary, the Nansemond River, which is a tributary of the James River in the Chesapeake Bay. Observations spanned two periods of nearly 3 months in autumn-winter of 2003-2004 and spring-summer 2004. The wind-driven circulation consisted of downwind flow over the shoal and upwind flow in the channel at the entrance to the estuary. This pattern developed mainly with landward winds and provided observational evidence that sustains analytical and numerical model results. The transverse structure of the flow showed …


Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins Jan 2008

Interactions Between Changing Pco2, N2 Fixation, And Fe Limitation In The Marine Unicellular Cyanobacterium Crocosphaera, Fei-Xue Fu, Margaret R. Mulholland, Nathan S. Garcia, Aaron Beck, Mark E. Warner, Sergio A. Sañudo, David A. Hutchins

OES Faculty Publications

We examined the physiological responses of steady-state iron (Fe)-replete and Fe-limited cultures of the biogeochemically critical marine unicellular diazotrophic cyanobacterium Crocosphaera at glacial (19 Pa; 190 ppm), current (39 Pa; 380 ppm), and projected year 2100 (76 Pa; 750 ppm) CO2 levels. Rates of N2 and CO2 fixation and growth increased in step with increasing partial pressure of CO2 (pCO2), but only under Fe- replete conditions. N2) and carbon fixation rates at 75 Pa CO2 were 1.4-1.8-fold and 1.2-2.0-fold higher, respectively, relative to those at present day and glacial pCO2 …


Examining Granular Computing From A Modeling Perspective, Ying Xie, Jayasimha R. Katukuri, Vijay V. Raghavan Jan 2008

Examining Granular Computing From A Modeling Perspective, Ying Xie, Jayasimha R. Katukuri, Vijay V. Raghavan

Faculty Articles

In this paper, we use a set of unified components to conduct granular modeling for problem solving paradigms in several fields of computing. Each identified component may represent a potential research direction in the field of granular computing. A granular computing model for information analysis is proposed. The model may suggest that granular computing is an instrument for implementing perception based computing based on numeric computing. In addition, a novel granular language modeling technique is proposed for information extraction from web pages. This paper also suggests that the study of data mining in the framework of granular computing may address …


University Of Texas At Tyler Catalog, 2008 - 2010, University Of Texas At Tyler Jan 2008

University Of Texas At Tyler Catalog, 2008 - 2010, University Of Texas At Tyler

Catalogs

No abstract provided.


The Ownership Of The Internet And The World Wide Web In Vermont, Ida Kubiszewski Jan 2008

The Ownership Of The Internet And The World Wide Web In Vermont, Ida Kubiszewski

Institute for Sustainable Solutions Publications and Presentations

The internet is an interesting case, since it was created entirely with taxpayer's money by DARPA, while the world wide web was created at CERN in Switzerland and placed into the public domain voluntarily in 1993. The internet and web have many features of a commons, and many people refer to the "internet commons". Kubiszewski (pronounced cube- ih-shefski) explores the intricacies of the internet and world wide web to determine if internet companies are extracting economic rent from the public and how it could be recovered. She finds that companies are making a substantial profit by utilizing a resource that …


Life History Of The Predatory Mite Phytoseiulus Fragariae On Tetranychus Evansi And Tetranychus Urticae (Acari: Phytoseiidae, Tetranychidae) At Five Temperatures, Geraldo José Nascimento De Vasconcelos, Gilberto José De Moraes, Ítalo Delalibera Júnior, Markus Knapp Jan 2008

Life History Of The Predatory Mite Phytoseiulus Fragariae On Tetranychus Evansi And Tetranychus Urticae (Acari: Phytoseiidae, Tetranychidae) At Five Temperatures, Geraldo José Nascimento De Vasconcelos, Gilberto José De Moraes, Ítalo Delalibera Júnior, Markus Knapp

All Peer-Reviewed Publications

Tetranychus evansi Baker and Pritchard and Tetranychus urticae Koch (Acari: Tetranychidae) are important pests of Solanaceae in many countries. Several studies have demonstrated that T. urticae is an acceptable prey to many predatory mites, although the suitability of this prey depends on the host plant. T. evansi, has been shown to be an unfavorable prey to most predatory mites that have been tested against it. The predator Phytoseiulus fragariae Denmark and Schicha (Acari: Phytoseiidae) has been found in association with the two species in Brazil. The objective of this work was to compare biological parameters of P. fragariae on T. …


Evaluating U.S. Federal Marine Protected Areas Programs: A Comparative Analysis And Conceptual Framework, Rosemarie Ann Bradley Jan 2008

Evaluating U.S. Federal Marine Protected Areas Programs: A Comparative Analysis And Conceptual Framework, Rosemarie Ann Bradley

Antioch University Dissertations & Theses

Federal area-based marine protection and management in the United States is overseen by the National Marine Sanctuary Program, the National Estuarine Research Reserve System, the National Wildlife Refuge System, the National Park Service, and the National Marine Fisheries Service. Each agency and program represents a different approach to managing the oceans. Currently, no federal agency or program is responsible for evaluating the overall effectiveness of these programs. Evaluation is needed to determine whether programs are achieving their management objectives and conservation goals. Although evaluation protocols are legislatively mandated, implementation is inconsistent across programs.

Federal agencies have been criticized for failing …


Carbon Dioxide Concentration In Air Within The Nerja Cave (Malaga, Andalusia, Spain), Cristina Liñán, Iñaki Vadillo, Francisco Carrasco Jan 2008

Carbon Dioxide Concentration In Air Within The Nerja Cave (Malaga, Andalusia, Spain), Cristina Liñán, Iñaki Vadillo, Francisco Carrasco

International Journal of Speleology

From 2001 to 2005 the CO2 concentration of the air in the interior and exterior of the Nerja Cave was studied and its relation with the air temperature and visitor number. The average annual CO2 concentration outside of the cave is 320 ppmv, whilst inside, the mean concentration increases to 525 ppmv during autumn and winter, and in the order of 750 ppmv during spring and summer. The temporal variation of CO2 content in the air of the cave is strongly influenced by its degree of natural ventilation which is, in turn, determined by the difference between …


Environmental Monitoring In The Mechara Caves, Southeastern Ethiopia: Implications For Speleothem Palaeoclimate Studies, Asfawossen Asrat, Andy Baker, Melanie J. Leng, John Gunn, Mohammed Umer Jan 2008

Environmental Monitoring In The Mechara Caves, Southeastern Ethiopia: Implications For Speleothem Palaeoclimate Studies, Asfawossen Asrat, Andy Baker, Melanie J. Leng, John Gunn, Mohammed Umer

International Journal of Speleology

The interpretation of palaeoclimate records in speleothems depends on the understanding of the modern climate of the region, the geology, the hydrology above the caves, and the within-cave climate. Monitoring within-cave climate variability, geochemistry of speleothem-forming drip waters, and associated surface and groundwater, provides a modern baseline for interpretation of speleothem palaeohydrological and palaeoclimate records. Here, we present results of such monitoring of the Mechara caves in southeastern Ethiopia, conducted between 2004 and 2007. Results show nearly constant within-cave climate (temperature and humidity) in all caves, which generally reflects the surface climate. Groundwater and surface water geochemistry is similar across …


Photochemical Studies Of Nutraceuticals In The Presence Of Cyclodextrins, Zlata Tofzikovskaya, Christine O'Connor, Mary Mcnamara Jan 2008

Photochemical Studies Of Nutraceuticals In The Presence Of Cyclodextrins, Zlata Tofzikovskaya, Christine O'Connor, Mary Mcnamara

Conference Papers

The photostability studies of Folic acid and Menadione Sodium Bisulfite, also known as vitamin K3, were carried out in their aqueous solutions at room temperature. Solutions of Folic acid ( 4.8 x 10-5 M) and Menadione Sodium Bisulfite (4.0 x 10-4 M) were exposed to ultraviolet radiation at a wavelength of 365 nm. During exposure absorbance of both solutions was measured using a Perkin Elmer Lamda 900 UV/VIS/NIR Spectrometer. During the stability tests it was noted that addition of β Cyclodextrin (1:1 ratio) to aqueous solutions containing the vitamin slowed down the photodegradation process. The unique shape of Cyclodextrins allows …


On An Integrable Two-Component Camassa-Holm Shallow Water System, Adrian Constantin, Rossen Ivanov Jan 2008

On An Integrable Two-Component Camassa-Holm Shallow Water System, Adrian Constantin, Rossen Ivanov

Articles

The interest in the Camassa-Holm equation inspired the search for various generalizations of this equation with interesting properties and applications. In this letter we deal with such a twocomponent integrable system of coupled equations. First we derive the system in the context of shallow water theory. Then we show that while small initial data develop into global solutions, for some initial data wave breaking occurs. We also discuss the solitary wave solutions. Finally, we present an explicit construction for the peakon solutions in the short wave limit of system.


Algebraic Discretization Of The Camassa-Holm And Hunter-Saxton Equations, Rossen Ivanov Jan 2008

Algebraic Discretization Of The Camassa-Holm And Hunter-Saxton Equations, Rossen Ivanov

Articles

The Camassa-Holm (CH) and Hunter-Saxton (HS) equations have an interpretation as geodesic flow equations on the group of diffeomorphisms, preserving the H1 and H.1 right-invariant metrics correspondingly. There is an analogy to the Euler equations in hydrodynamics, which describe geodesic flow for a right-invariant metric on the infinitedimensional group of diffeomorphisms preserving the volume element of the domain of fluid flow and to the Euler equations of rigid body whith a fixed point, describing geodesics for a left-invariant metric on SO(3). The CH and HS equations are integrable bi-hamiltonian equations and one of their Hamiltonian structures is associated to the …


Non-Existence Of A Minimizer To The Hartree-Fock Functional, Michael Melgaard, Mattias Enstedt Jan 2008

Non-Existence Of A Minimizer To The Hartree-Fock Functional, Michael Melgaard, Mattias Enstedt

Articles

In the presence of an external magnetic field, we prove absence of a ground state within the Hartree-Fock theory of atoms and molecules. The result is established for a wide class of magnetic fields when the number of electrons is greater than or equal to 2Z + K, where Z is the total charge of K nuclei. Positivity properties are instrumental in the proof of this bound for the maximal ionization


Existence Of A Solution To Hartree-Fock Equations With Decreasing Magnetic Field, Mattias Enstedt, Michael Melgaard Jan 2008

Existence Of A Solution To Hartree-Fock Equations With Decreasing Magnetic Field, Mattias Enstedt, Michael Melgaard

Articles

In the presence of an external magnetic field, we prove existence of a ground state within the Hartree–Fock theory of atoms and molecules. The ground state exists provided the magnetic field decreases at infinity and the total charge of nuclei exceeds , where is the number of electrons. In the opposite direction, no ground state exists if .


Medical Language Processing For Patient Diagnosis Using Text Classification And Negation Labelling, Brian Mac Namee, John D. Kelleher, Sarah Jane Delany Jan 2008

Medical Language Processing For Patient Diagnosis Using Text Classification And Negation Labelling, Brian Mac Namee, John D. Kelleher, Sarah Jane Delany

Conference papers

This paper describes the approach of the DIT AIGroup to the i2b2 Obesity Challenge to build a system to diagnose obesity and related co-morbidities from narrative, unstructured patient records. Based on experimental results a system was developed which used knowledge-light text classification using decision trees, and negation labelling.


Referring Expression Generation Challenge 2008 Dit System Descriptions (Dit-Fbi, Dit-Tvas, Dit-Cbsr, Dit-Rbr, Dit-Fbi-Cbsr, Dit-Tvas-Rbr), John D. Kelleher, Brian Mac Namee Jan 2008

Referring Expression Generation Challenge 2008 Dit System Descriptions (Dit-Fbi, Dit-Tvas, Dit-Cbsr, Dit-Rbr, Dit-Fbi-Cbsr, Dit-Tvas-Rbr), John D. Kelleher, Brian Mac Namee

Conference papers

This papers desibes a set of systems developed at DIT for the Referring Expression Generation challenage at INLG 2008.In Proceedings of the 5th International Natural Language Generation Conference (INLG-08)


Systematic Synthesis And Study Of The Structure-Property Relationships Of Arylene Vinylene Polymers., Patrick Lynch Jan 2008

Systematic Synthesis And Study Of The Structure-Property Relationships Of Arylene Vinylene Polymers., Patrick Lynch

Doctoral

Much is known about the electronic, vibrational and steric effects resulting from the addition of differing organic functional groups as side chains, to the parent conjugated polymer. However the same cannot be said about the substitution of constituents of the polymer backbone itself. To this end a study is presented here which systematically studies the effects of naphthalene and anthracene substitution of the properties of poly phenylene vinylene (PPV) derivative conjugated polymers. The synthesis by the Witting-Horner reaction of derivatives is presented whereby the phenylene units of the PPV structure are methodically substituted by naphthylene and anthrylene units to form …


Hydrodynamic Aspect Of Caves, Mitja Prelovšek, Janez Turk, Franci Gabrovšek Jan 2008

Hydrodynamic Aspect Of Caves, Mitja Prelovšek, Janez Turk, Franci Gabrovšek

International Journal of Speleology

From a hydrological point of view, active caves are a series of connected conduits which drain water through an aquifer. Water tends to choose the easiest way through the system but different geological and morphological barriers act as flow restrictions. The number and characteristics of restrictions depends on the particular speleogenetic environment, which is a function of geological, geomorphological, climatological and hydrological settings. Such a variety and heterogeneity of underground systems has presented a challenge for human understanding for many centuries. Access to many underground passages, theoretical knowledge and recent methods (modeling, water pressure-resistant dataloggers, precise sensors etc.) give us …


Beyond The Debate: Exploring The Underlying Values And Assumptions Of Biodiversity Conservation In Protected Areas, Leon-Charl Malan Jan 2008

Beyond The Debate: Exploring The Underlying Values And Assumptions Of Biodiversity Conservation In Protected Areas, Leon-Charl Malan

Antioch University Dissertations & Theses

This dissertation examines the current disagreement among scientists and scholars about best practices for biodiversity conservation in protected areas. There is no clear consensus among the scientific community about the most effective approach to conserve biodiversity and several conflicting positions form part of an ongoing debate in the field. Most disagreements and conflicts are based on differences in the underlying values and assumptions of the parties involved in the conflict. The more we know and understand those underlying values, the more constructive the dialog, and the more likely acceptable policy decisions will be developed. This study, presented in three parts, …


Integration Of Analysis And Deliberation To Evaluate Biodiesel Occupational And Environmental Exposures, Nora M. Traviss Jan 2008

Integration Of Analysis And Deliberation To Evaluate Biodiesel Occupational And Environmental Exposures, Nora M. Traviss

Antioch University Dissertations & Theses

Many U.S. organizations interested in a renewable and domestic source of energy are considering switching from petroleum diesel to biodiesel blends for transportation and heavy-duty equipment use. Biodiesel is a fuel made from vegetable oils or waste grease. While there is a considerable body of evidence on the negative health effects of petroleum diesel exhaust exposures in occupational and urban settings, there has been little research examining the impact of biodiesel fuel on occupational and environmental exposures. This dissertation combined a collaborative exposure assessment of B20 (20% soy-based biodiesel/80% diesel) at a rural recycling center with a policy intervention to …


Connecting With Nature Through Land Use Decision Making, Cathy Setterlin Jan 2008

Connecting With Nature Through Land Use Decision Making, Cathy Setterlin

Antioch University Dissertations & Theses

This narrative inquiry, which draws on my experience as a land use decision maker, environmental educator, and scholar, examines the complexities of our human-nature relationship as we use and protect the life of the land in local communities. I began this research by interviewing seventeen land use decision makers representing a range of land use perspectives in New Milford, Connecticut, focusing on their views of land as a living community, their connections to land, and their sense of duty and responsibility.

Their responses led me to further inquiry and drew me into a process that transformed my views of both …


The Ecology Of Paradox: Disturbance And Restoration In Land And Soul, Rowland S. Russell Jan 2008

The Ecology Of Paradox: Disturbance And Restoration In Land And Soul, Rowland S. Russell

Antioch University Dissertations & Theses

This heuristic study explores environmental disturbance and ecological restoration in several North American settings in order to uncover epistemological, philosophical, aesthetic and ethical considerations revolving around those place-based processes. With fire as one of the central metaphors of this work, the initial place-based chapter examines Northern New Mexico's Pajarito Plateau to explore the region's fire ecology. The study then moves to the Pacific Northwest to draw restoration practice that attempt to restore wild salmon to urban Seattle habitat. The third place-based chapter focuses on the Midwest grass and farmlands in order to investigate the seeming contradictions between commodity and diversity …


Fostering Sustainability In Higher Education: A Mixed-Methods Study Of Transformative Leadership And Change Strategies, Kim H. Mcnamara Jan 2008

Fostering Sustainability In Higher Education: A Mixed-Methods Study Of Transformative Leadership And Change Strategies, Kim H. Mcnamara

Antioch University Dissertations & Theses

As evidence of the earth’s limited capacity to sustain human life mounts, institutions of higher education are being looked to for leadership in the effort to educate students about environmental concerns and support the development of sustainable innovations. Colleges and universities are responding to this call for leadership by starting and/or expanding environmental research programs, integrating sustainability issues throughout the curriculum, adopting sustainable operations, and building green facilities. Reflecting upon the sustainability efforts of these institutions, this research study explores the following questions: What factors are essential for initiating and leading a successful change effort to foster sustainability in higher …


Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural Jan 2008

Zinc Perchlorate Hexahydrate Catalyzed Mono- And Bis-Transesterification Of Malonic Esters, Servet Tural

Turkish Journal of Chemistry

Commercially available zinc perchlorate hexahydrate [Zn(ClO_4)_2.6H_2O] was found to be a highly effective catalyst for the transesterification of malonic esters with alcohols. The treatment of methyl-, ethyl-, or \alpha-substituted malonic esters with primary or secondary alcohols in the presence of a catalytic amount of zinc perchlorate results in good to high yields of the corresponding esters (68%-99%). Mono-transesterification products are also obtained in moderate to good yields (22%-42%). The reaction was also carried out with 2-mono- and di-substituted malonic esters, and in the case of 2-mono- and di-substituted malonic esters, the reaction time is, in some cases, shorter, in which …