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  Partner: UNT College of Arts and Sciences
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Homogenization of Magnetodielectric Photonic Crystals

Homogenization of Magnetodielectric Photonic Crystals

Date: July 9, 2004
Creator: Krokhin, Arkadii A. & Reyes, E.
Description: This article discusses homogenization of magnetodielectric photonic crystals. Abstract: We calculate the low-frequency index of refraction of a medium which is homogeneous along axis z and possesses a periodic dependence of the permittivity ɛ(r) and permeability μ(r) in the x-y plane (2D magnetodielectric photonic crystal). Exact analytical formulas for the effective index of refraction for two eigenmodes with vector E or H polarized along axis z are obtained. We show that, unlike nonmagnetic photonic crystals where the E mode is ordinary and the H mode is extraordinary, now both modes exhibit extraordinary behavior. Because of this distinction, the magnetodielectric photonic crystals exhibit optical properties that do not exist for natural crystals. We also discuss the limiting case of perfectly conducting cylinders and clarify the so-called problem of noncommuting limits, ω → 0 and ɛ → ∞.
Contributing Partner: UNT College of Arts and Sciences
How to Hook a Hottie: Teenage Boys, Hegemonic Masculinity, and Cosmo Girl! Magazine

How to Hook a Hottie: Teenage Boys, Hegemonic Masculinity, and Cosmo Girl! Magazine

Date: 2011
Creator: Enck-Wanzer, Suzanne M. & Murray, Scott A.
Description: This book chapter discusses different media texts targeted at a different audience, magazines written for an audience of teenaged girls, which also work to naturalize male sexuality as aggressive and predatory. The authors study advice columns and articles in these magazines that depict teenaged boys as sexually forceful and emotionally stunted, and that encourage girl readers to expect and enable such behaviors.
Contributing Partner: UNT College of Arts and Sciences
The Hunting Behavior of Black-Shouldered Kites (Elanus Caeruleus Leucurus) in Central Chile

The Hunting Behavior of Black-Shouldered Kites (Elanus Caeruleus Leucurus) in Central Chile

Date: 1987
Creator: Jaksić, Fabian M.; Rozzi, Ricardo, 1960-; Labra, Antonieta & Jiménez, Jaime
Description: This article discusses the hunting behavior of black-shouldered kites in central Chile. Abstract: Kites of the genus Elanus are found throughout the world principally in open areas such as grasslands, sparse shrublands, and agricultural fields (Brown and Amadon 1968). Because of their characteristic hover-hunting, and their widespread distribution, these kites make interesting subjects for analyses of their hunting behavior. Such studies have been conducted in several regions, including North America (Waian and Stendall 1970, Warner and Rudd 1974, Koplin et al. 1980), Europe (Amat 1979, Heredia 1983), Africa (Tarboton 1978, Mendelsohn 1982), and Australia (Baker-Gabb 1984). However, quantitative information on the hunting behavior of South American kites was nonexistent until now, and is reported here from a locality in central Chile.
Contributing Partner: UNT College of Arts and Sciences
Hydrogen-Deuerium Exchange between TpRu(PMe3)(L)X (L = PMe3 and X = OH, OPh, Me, Ph, or NHPh; L = NCMe and X = Ph) and Deuterated Arene Solvents: Evidence for Metal-Mediated Processes

Hydrogen-Deuerium Exchange between TpRu(PMe3)(L)X (L = PMe3 and X = OH, OPh, Me, Ph, or NHPh; L = NCMe and X = Ph) and Deuterated Arene Solvents: Evidence for Metal-Mediated Processes

Date: May 24, 2006
Creator: Feng, Yuee; Lail, Marty; Foley, Nicholas A.; Gunnoe, T. Brent; Barakat, Khaldoon A.; Cundari, Thomas R., 1964- et al
Description: This article discusses evidence for metal-mediated processes. Abstract: At elevated temperatures (90-130 ˚C), complexes of the type TpRu(PMe3)2X (X = OH, OPh, Me, Ph, or NHPh; Tp = hydridotris(pyrazolyl)borate) undergo regioselective hydrogen-deuterium (H/D) exchange with deuterated arenes. For X = OH or NHPh, H/D exchange occurs at hydroxide and anilido ligands, respectively. For X = OH, OPh, Me, Ph, or NHPh, isotopic exchange occurs at the Tp 4-positions with only minimal deuterium incorporation at the Tp 3- or 5-positions or PMe3 ligands. For TpRu(PMe3)-(NCMe)Ph, the H/D exchange occurs at 60 ˚C at all three Tp positions and the phenyl ring. TpRu(PMe3)2-CI, TpRu(PMe3)2OTf(OTf = trifluoromethanesulfonate), and TpRu(PMe3)2SH do not initiate H/D exchange in C6D6 after extended periods of time at elevated temperatures. Mechanistic studies indicate that the likely pathway for the H/D exchange involves ligand dissociation (PMe3 or NCMe), Ru-mediated activation of an aromatic C-D bond, and deuteration of basic nondative ligand (hydroxide or anilido) or Tp positions via net D+ transfer.
Contributing Partner: UNT College of Arts and Sciences
Identification of functional information subgraphs in cultured neural networks

Identification of functional information subgraphs in cultured neural networks

Date: July 13, 2009
Creator: Gintautas, Vadas; Bettencourt, Luis & Ham, Michael I.
Description: This paper accompanies an oral presentation on the identification of functional information subgraphs in cultured neural networks. Abstract: We present a general information theoretic approach for identifying functional subgraphs in complex neuronal networks where the spiking dynamics of a subset of nodes (neurons) are observable. We show that the uncertainty in the state of each node can be written as a sum of information quantities involving a growing number of variables at other nodes. We demonstrate that each term in this sum is generated by successively conditioning mutual information on new measured variables, in a way analogous to a discrete differential calculus.
Contributing Partner: UNT College of Arts and Sciences
Identification of Phloem Involved in Assimilate Loading in Leaves by the Activity of the Galactinol Synthase Promoter

Identification of Phloem Involved in Assimilate Loading in Leaves by the Activity of the Galactinol Synthase Promoter

Date: July 2000
Creator: Haritatos, Edith Emily, 1969-; Ayre, Brian G. & Turgeon, Robert
Description: This article discusses identification of phloem. Abstract: The definition of "minor" veins in leaves is arbitrary and of uncertain biological significance. Generally, the term refers to the smallest vein classes in the leaf, believed to function in phloem loading. The authors found that a galactinol synthase promoter, cloned from melon (Cucumis melo), directs expression of the gusA gene to the smallest veins of mature Arabidopsis and cultivated tobacco (Nicotiana tabacum) leaves. This expression pattern is consistent with the role of galactinol synthase in sugar synthesis and phloem loading in cucurbits. The expression pattern in tobacco is especially noteworthy since galactinol is not synthesized in the leaves of this plant. Also, the authors unexpectedly found that expression in tobacco is limited to two of three companion cells in class-V veins, which are the most extensive in the leaf. Thus, the "minor" vein system is defined and regulated at the genetic level, and there is heterogeneity of response to this system by different companion cells of the same vein.
Contributing Partner: UNT College of Arts and Sciences
Implicaciones éticas de narrativas Yaganes y Mapuches sobre las aves de los bosques templados de Sudamérica austral

Implicaciones éticas de narrativas Yaganes y Mapuches sobre las aves de los bosques templados de Sudamérica austral

Date: 2004
Creator: Rozzi, Ricardo, 1960-
Description: This article discusses the ethical implications of Yahgan and Mapuches narratives of the birds of the temperate forests of southern South America. Abstract: This paper analyzes the ethical implications of Yahgan and Mapuche stories about forest birds of southern Chile and Argentina, from the perspective of biological conservation and environmental philosophy. To allow comparisons among notions of traditional ecological knowledge, evolutionary-ecological sciences, and environmental ethics, the author focuses in two well known metaphors: the "tree of life" and the "web of life". The analysis of the first metaphor allows to conclude that both modern sciences and the Yahgan and Mapuche indigenous cosmogonies affirm a common origin for birds and humans. This notion supports the intrinsic value of the avifauna, because birds are regarded as our evolutionary relatives. This implies that, to a certain degree, the life of birds can be subject to moral considerations based on ontological and ethical judgements commensurable with those involved in assessing the value of human life. The analysis of the metaphor of the "web of life" also reveals essential correspondences between contemporary scientific knowledge and Yahgan and Mapuche traditional ecological knowledge regarding the net of biotic interactions and ecosystem processes. Bird stories such as the ...
Contributing Partner: UNT College of Arts and Sciences
Inhomogeneous DNA: Conducting exons and insulating introns

Inhomogeneous DNA: Conducting exons and insulating introns

Date: August 17, 2009
Creator: Krokhin, Arkadii A.; Bagci, V. M. K.; Izrailev, Felix M.; Usatenko, O. V. & Yampol'skii, V. A.
Description: This article discusses inhomogeneous DNA. Abstract: Parts of DNA sequences known as exons and introns play very different roles in coding and storage of genetic information. Here, the authors show that their conducting properties are also very different. Taking into account long-range correlations among four basic nucleotides that form double-stranded DNA sequence, the authors calculate electron localization length for exon and intron regions. Analyzing different DNA molecules, the authors obtain that the exons have narrow bands of extended states, unlike the introns where all the states are well localized. The band of extended states is due to a specific form of the binary correlation function of the sequence of basic DNA nucleotides.
Contributing Partner: UNT College of Arts and Sciences
Input Substitution in Irrigated Agriculture in the High Plains of Texas, 1970-80

Input Substitution in Irrigated Agriculture in the High Plains of Texas, 1970-80

Date: July 1988
Creator: Nieswiadomy, Michael L.
Description: This article discusses input substitution in irrigated agriculture in the high plains of Texas. Abstract: The adaptability of irrigated agriculture in the High Plains region of Texas in the 1970-80 period is analyzed by estimating Allen partial elasticities of substitution for five key inputs (water, labor, center pivot, furrow, and wheel roll systems) used to produce two crops (cotton and grain sorghum). The results indicate that farmers have adapted to changes in a manner generally consistent with prior expectations concerning complementarity and substitutability among inputs. The output-constant price elasticity of water demand was statistically significant but relatively small (-.25).
Contributing Partner: UNT College of Arts and Sciences
Integrando la Ciencia y la Sociedad a través de la Investigación Socio-Ecológica de Largo Plazo

Integrando la Ciencia y la Sociedad a través de la Investigación Socio-Ecológica de Largo Plazo

Date: 2008
Creator: Anderson, Christopher B.; Likens, Gene E., 1935-; Rozzi, Ricardo, 1960-; Gutiérrez, Julio R., 1953-; Armesto, Juan J., 1953- & Poole, Alexandria
Description: This article discusses integrating science and society through long-term socio-ecological research. Abstract: Long-term ecological research (LTER), addressing problems that encompass decadal or longer time frames, began as a formal term and program in the United States in 1980. While long-term ecological studies and observation began as early as the 1400s and 1800s in Asia and Europe, respectively, the long-term approach was not formalized until the establishment of the U.S. long-term ecological research programs. These programs permitted ecosystem-level experiments and cross-site comparisons that led to insights into the biosphere's structure and function. The holistic ecosystem approach of this initiative also allowed the incorporation of the human-dimension of ecology and recently has given rise to a new concept of long-term socio-ecological research (LTSER). Today, long-term ecological research programs exist in at least thirty-two countries (i.e., members of the International Long-Term Ecological Research Network, ILTER). However, consolidation of the international network within the long-term socio-ecological research paradigm still requires: (1) inclusion of certain remote regions of the world, such as southwestern South America, that are still poorly represented; (2) modifications of the type of research conducted, such as integrating social and natural sciences with the humanities and ethics; and (3) the incorporation of ...
Contributing Partner: UNT College of Arts and Sciences