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1999

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Full-Text Articles in Physical Sciences and Mathematics

Satellite-Based Adjustments For The Urban Heat Island Temperature Bias, Kevin P. Gallo, Timothy W. Owen Jan 1999

Satellite-Based Adjustments For The Urban Heat Island Temperature Bias, Kevin P. Gallo, Timothy W. Owen

School of Natural Resources: Faculty Publications

Monthly and seasonal relationships between urban–rural differences in minimum, maximum, and average temperatures measured at surface-based observation stations were compared to satellite-derived Advanced Very High Resolution Radiometer estimates of a normalized difference vegetation index (NDVI) and surface radiant temperature.


A Revised Measurement Methodology For Conifer Needles Spectral Optical Properties: Evaluating The Influence Of Gaps Between Elements, Mark A. Mesarch, Elizabeth Walter-Shea, Gregory P. Asner, Elizabeth M. Middleton, Stephen Chan Jan 1999

A Revised Measurement Methodology For Conifer Needles Spectral Optical Properties: Evaluating The Influence Of Gaps Between Elements, Mark A. Mesarch, Elizabeth Walter-Shea, Gregory P. Asner, Elizabeth M. Middleton, Stephen Chan

School of Natural Resources: Faculty Publications

Gaps are unavoidable when compositing small or narrow plant parts (e.g., conifer needles, twigs, narrow leaves, and leaflets) on sample holders in preparation for measuring spectral optical properties. The Daughtry et al. (1989) (A new technique to measure the spectral properties of conifer needles. Remote Sens. Environ. 27:81-91.) method of measuring conifer needle optical properties utilizes a relatively large gap fraction (approximately 0.3-0.6) and needles painted black on one surface of the sample from which the gap fraction of the sample is indirectly determined. Following this protocol typically results in distortions in optical properties, including underestimates in transmittance (sometimes negative …


The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski Jan 1999

The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski

School of Natural Resources: Faculty Publications

Habitat fragmentation has been implicated as a major cause of population decline in grassland birds. We tested the hypothesis that a combination of area and shape determines the use of grassland patches by breeding birds. We compared both species richness and individual species presence in 45 wet meadow grasslands in the floodplain of the central Platte River, Nebraska. Bird data were collected through the use of belt transects and supplemented by walking and listening outside transects. Our data supported our primary hypothesis that perimeter–area ratio, which reflects both the area and shape of a patch, is the strongest predictor of …


Iron-Mediated Remediation Of Rdx-Contaminated Water And Soil Under Controlled Eh/Ph, J. Singh, Steven Comfort, Patrick Shea Jan 1999

Iron-Mediated Remediation Of Rdx-Contaminated Water And Soil Under Controlled Eh/Ph, J. Singh, Steven Comfort, Patrick Shea

School of Natural Resources: Faculty Publications

Soil and water contaminated with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a serious environmental problem at several active and abandoned munitions production facilities. Zero-valent iron (Fe0) can effectively remediate RDX-contaminated soil and water. The objective of this study was to manipulate Eh and pH for enhanced Fe0-mediated destruction of RDX. This was accomplished by monitoring RDX destruction under controlled Eh-pH conditions (Eh: −300 to +150 mV; pH: 2−10). Decreasing Eh and pH increased RDX destruction in aqueous solution. Treating 20 mg of RDX L-1 (90 μM) under a static Eh of −150 mV and pH 7 with 20 g …


Molecular Composition Of The Louse Sheath, Craig N. Burkhart, B Artur Stankiewicz, Irene Pchalek, Michael A. Kruge, Craig G. Burkhart Jan 1999

Molecular Composition Of The Louse Sheath, Craig N. Burkhart, B Artur Stankiewicz, Irene Pchalek, Michael A. Kruge, Craig G. Burkhart

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Flash pyrolysis-gas chromatography/mass spectrometry was used to assess the chemical composition of the head louse's nit sheath. The pyrolyzate of the female insect's secretions, which form a cement-like cylinder holding the egg onto the hair, is dominated by amino acid derivatives and fatty acids. No chitin-specific compounds were detected in the sheath. These results, contrary to previous reports, show that the polymeric complex of the sheath is composed of proteinaceous moieties, possibly cross-linked to aliphatic components. This study constitutes the first chemical characterization of the pyrolysis products of insect (louse) glue and unequivocally confirms that louse sheaths are not chitinous, …


Classification Of Torbanite And Cannel Coal. Ii. Insights From Organic Geochemical And Multivariate Statistical Analysis, Zhiwen Han, Michael A. Kruge Jan 1999

Classification Of Torbanite And Cannel Coal. Ii. Insights From Organic Geochemical And Multivariate Statistical Analysis, Zhiwen Han, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Petrographic and megascopic criteria have traditionally been used as the basis for the classification of torbanite and cannel coal. For this study, it was hypothesized that modern analytical organic geochemical and multivariate statistical techniques could provide an alternative approach. Towards this end, the demineralized residues of 14 torbanite (rich in Botryococcus-related alginite) and cannel (essentially, rich in organic groundmass and/or sporinite) coal samples were analyzed by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster analysis performed on the Py-GC/MS data clearly distinguished the torbanite from the cannel coal, demonstrating a consistency between the chemical properties and the petrographic composition. All the torbanite …


Contents Jan 1999

Contents

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Journal Of Mathematics And Science: Collaborative Explorations Jan 1999

Journal Of Mathematics And Science: Collaborative Explorations

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Algebra And Calculus For All?, Z. Usiskin Jan 1999

Algebra And Calculus For All?, Z. Usiskin

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Shaping The Future Of Teacher Preparation In Science And Mathematics, M. George Jan 1999

Shaping The Future Of Teacher Preparation In Science And Mathematics, M. George

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Student Discovery And Learning Through Precalculus Cbl Projects, R. Farley, K. Wallo Jan 1999

Student Discovery And Learning Through Precalculus Cbl Projects, R. Farley, K. Wallo

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


An Undergraduate Intern Model For Mathematics Teacher Preparation, R. Ford, W. Fisher Jan 1999

An Undergraduate Intern Model For Mathematics Teacher Preparation, R. Ford, W. Fisher

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


The Use Of Research To Inform The Evaluation Of The Maryland Collaborative For Teacher Preparation, J. Mcginnis, T. Watanabe Jan 1999

The Use Of Research To Inform The Evaluation Of The Maryland Collaborative For Teacher Preparation, J. Mcginnis, T. Watanabe

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


Educational Research Abstracts, G. Bass Jr. Jan 1999

Educational Research Abstracts, G. Bass Jr.

Journal of Mathematics and Science: Collaborative Explorations

Editors' Note: As noted in previous issues of the Journal of Mathematics and Science: Collaborative Explorations, the purpose of this Educational Research Abstract section is to present current published research on issues relevant to math and science teaching at both the K-12 and college levels. Because educational research articles are published in so many different academic journals, it is a rare public school teacher or college professor who reads all the recent published reports on a particular instructional technique or curricular advancement. Indeed, the uniqueness of various pedagogical strategies has been tacitly acknowledged by the creation of individual journals dedicated …


Aims & Scope Jan 1999

Aims & Scope

Journal of Mathematics and Science: Collaborative Explorations

No abstract provided.


A Summer Academy Program For Prospective Teachers: Model Teaching Experiences, M. Neathery Jan 1999

A Summer Academy Program For Prospective Teachers: Model Teaching Experiences, M. Neathery

Journal of Mathematics and Science: Collaborative Explorations

This article describes the project, A Summer Academy Program for Prospective Teachers: Model Teaching Experiences, of the Oklahoma Teacher Education Collaborative (O-TEC), one of the nation’s Collaboratives for Excellence in Teacher Preparation (CETP). To recruit highly qualified teachers in science and mathematics, O-TEC institutions promote a program of summer academies that provide prospective teachers with opportunities to become familiar with effective teaching methods. During the academy, high school juniors and seniors explore inquiry-based teaching strategies, exemplary curricula, science and math content, and state and national standards in math and science education-all under the tutelage of mentor teachers, a Master-Teacher-in- Residence, …


Addressing Prospective Elementary Teachers' Beliefs About The Nature Of Mathematics: A Case For Exploring Students' Conceptions Of Mathematics In A Math Education Course, K. Dorgan Jan 1999

Addressing Prospective Elementary Teachers' Beliefs About The Nature Of Mathematics: A Case For Exploring Students' Conceptions Of Mathematics In A Math Education Course, K. Dorgan

Journal of Mathematics and Science: Collaborative Explorations

Our challenge in preparing Virginia’s K-8 teachers in mathematics is a complex one. Additional requirements, including more challenging math content courses or more innovative pedagogical courses, may provide part of the solution. It is the premise of this paper, however, that additional knowledge and skills are not enough. In order to prepare teachers who will engage in current best practice pedagogy, we must also address teachers’ attitudes and dispositions, their beliefs and conceptions of mathematics itself. This paper will attempt to justify this position. It will also describe strategies used in the Inquiry in Mathematics course in Mary Baldwin’s MAT …


Technology Integration In A Science And Mathematics Methods Course: Addressing Virginia's Computer/Technology Standards Of Learning, G. Meadows, M. Sheckels Jan 1999

Technology Integration In A Science And Mathematics Methods Course: Addressing Virginia's Computer/Technology Standards Of Learning, G. Meadows, M. Sheckels

Journal of Mathematics and Science: Collaborative Explorations

The Standards of Learning for Virginia Public Schools [1] require a high level of knowledge in the use of computers and technology on the part of both students and educators. The Education Department at Mary Washington College has decided to prepare its students to meet this challenge by adopting a strategy of program wide integration of technology, bringing appropriate uses of technology into each education course. This strategy calls for the use of technology by both students and instructors. The course Instructional Skills in the Elementary Classroom, a science and mathematics planning course, served as a proving ground for this …


Does N-2(-) Exist? A Coupled-Cluster Study, Gennady L. Gutsev, Piotr B. Rozyczko, Rodney J. Bartlett, Charles A. Weatherford Jan 1999

Does N-2(-) Exist? A Coupled-Cluster Study, Gennady L. Gutsev, Piotr B. Rozyczko, Rodney J. Bartlett, Charles A. Weatherford

Physics Publications

Potential energy curves of the ground-state N2 molecule and its doublet N−2 anion are calculated at the coupled-cluster level with single and double excitations and with noniterative triples [CCSD(T)] as well as with the multireference averaged-quadratic coupled-cluster (MR-AQCC) method. The N−2 anion is shown to be temporary and decays to its neutral parent plus a free electron at bond lengths shorter than ≈1.4 and larger than ≈2.5 Å. Thus, the N−2 anion exists within the 1.4⩽R(N–N)⩽2.5 Å range at the Born–Oppenheimer approximation.


Manejo Del Agua En Las Acequias Privadas Garrapatal Y El Tambo En La Provincia Del Carchi, Ecuador, Jorge Sotomayor, Wim H. Kloezen, Elena Bastidas Jan 1999

Manejo Del Agua En Las Acequias Privadas Garrapatal Y El Tambo En La Provincia Del Carchi, Ecuador, Jorge Sotomayor, Wim H. Kloezen, Elena Bastidas

Conflict Resolution Studies Faculty Articles

Como parte de las actividades que el Instituto Internacional del Manejo del Agua (IWMI, por su sigla en Inglés) adelantó en la Región Andina se llevó a cabo el estudio que aquí se presenta. El Banco Interamericano de Desarrollo otorgó una donación al Intituto a fin de valuar, entre otras cosas, el manejo de los sistemas de riego privados en las partes altas del Ecuador. Fue así como se escogieron dos acequias en la Provincia del Carchi: Garrapatal y el Tambo. El estudio representa un esfuerzo significativo por parte de los autores ya que las condiciones geográficas del área constituyen …


Epi-And Mesopelagic Fishes, Acoustic Data, And Sst Images Collected Off Lanzarote, Fuerteventura, And Gran Canaria, Canary Islands, During Cruise "La Bocaina 04-97", F. Bordes, F. Uiblein, R. Castillo, A. Barrera, J. J. Castro, J. Coca, J. Gomez, K. Hansen, V. Hernandez, N. Merrett, M. Miya, T. Moreno, F. Perez, A. Ramos, Tracey Sutton, M. Yamaguchi Jan 1999

Epi-And Mesopelagic Fishes, Acoustic Data, And Sst Images Collected Off Lanzarote, Fuerteventura, And Gran Canaria, Canary Islands, During Cruise "La Bocaina 04-97", F. Bordes, F. Uiblein, R. Castillo, A. Barrera, J. J. Castro, J. Coca, J. Gomez, K. Hansen, V. Hernandez, N. Merrett, M. Miya, T. Moreno, F. Perez, A. Ramos, Tracey Sutton, M. Yamaguchi

Marine & Environmental Sciences Faculty Reports

During cruise "La Bocaina 0497" a series of 14 tows with a commercial pelagic trawl at depths between 20 and 700 m and an acoustic survey with a SIMRAD EK-500 echosounder were carried out in neritic and adjacent oceanic waters off Lanzarote, Fuerteventura, and Gran Canaria, Canary islands. In addition, SST images were obtained to get some informations on the prevailing hydrological conditions in the study area.

Of the 14 trawl tows ten were successful and resulted in capture of a total of 2166 fishes belonging to 81 species, 53 genera and 28 families. Ten species proved to be new …


Sea Turtle Conservation Program, Broward County, Fl 1999 Report, Curtis M. Burney, William E. Margolis Jan 1999

Sea Turtle Conservation Program, Broward County, Fl 1999 Report, Curtis M. Burney, William E. Margolis

Marine & Environmental Sciences Faculty Reports

No abstract provided.


Skeletal Architecture And Density Banding Analysis Technique For Diploria Strigosa By X-Ray Computed Tomography, Kevin P. Helmle, Richard E. Dodge (Editor) Jan 1999

Skeletal Architecture And Density Banding Analysis Technique For Diploria Strigosa By X-Ray Computed Tomography, Kevin P. Helmle, Richard E. Dodge (Editor)

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Coral skeletal density information is a useful growth parameter and may be coupled with extension rates to determine calcification rates. The conventional process for density determination is often cumbersome and requires some parameters which are difficult to precisely specify (e.g., Mass absorption coefficients). We have developed a technique and windows based computer program which enables the rapid collection of coral density data. The coral skeleton slab is xradiographed with an aluminum wedge. Thickness and density of the aluminum wedge, thickness of the coral slab, density of pure coral aragonite, and digitized images of the coral and wedge x-radiographs provide necessary …


Winter 1999, Nsu Oceanographic Center Jan 1999

Winter 1999, Nsu Oceanographic Center

Currents

No abstract provided.


1999-2000 Nova Southeastern University Center For Undergraduate Studies Catalog, Nova Southeastern University Jan 1999

1999-2000 Nova Southeastern University Center For Undergraduate Studies Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.


Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo Jan 1999

Iron-Induced Oxidative Stress In Erythrocyte Membranes Of Non-Insulin-Dependent Diabetic Nigerians, Gbolahan W. Okunade, Odutayo O. Odunuge, Olufunso O. Olorunsogo

Faculty Publications

The presence of higher level of endogenous free radical reaction products in the erythrocyte ghost membrane (EGM) of Non-insulin-dependent diabetes mellitus (NIDDM) subjects compared with that of normal healthy controls has been demonstrated. The EGMs of NIDDM subjects were also shown to be more susceptible to exogenously generated oxidative stress than those of normal healthy individuals. The decreased level of reactive thiol groups in the EGM of NIDDM individuals supported this observation. We propose that the presence of significant levels of non-heme iron in the EGM of NIDDM subjects is an indication of the potential for iron-catalysed production of hydroxy …


Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo Jan 1999

Reversal Of Sodium Arsenite Inhibition Of Rat Liver Microsomal Ca2+ Pumping Atpase By Vitamin C, Odutayo O. Odunuge, Gbolahan W. Okunade, Olufunso O. Olorunsogo

Faculty Publications

Sodium arsenite (NaAsO2), at 10% of its median lethal dose, was administered to rats with and without vitamin C pretreatment. Liver microsomal fraction was isolated and the activity of Ca2+-ATPase was assayed. Sodium arsenite was found to inhibit the activity of the liver microsomal Ca2+-ATPase to 50% to that of control rats. The specific activity of the enzyme in rats administered sodium arsenite with vitamin C pretreatment was not significantly different from that of control rats.


Routing And Wavelength Assignment (Rwa) With Power Considerations In All- Optical Wavelength-Routed Networks, Maher Ali, Byrav Ramamurthy, Jitender S. Deogun Jan 1999

Routing And Wavelength Assignment (Rwa) With Power Considerations In All- Optical Wavelength-Routed Networks, Maher Ali, Byrav Ramamurthy, Jitender S. Deogun

CSE Conference and Workshop Papers

Routing and wavelength assignment (RWA) is an important problem that arises in wavelength division multiplexed (WDM) optical networks. Previous studies have solved many variations of this problem under the assumption of perfect conditions regarding the power of a signal. In this paper, we investigate this problem while allowing for degradation of routed signals by components such as taps, multiplexers, and fiber links. We assume that optical amplifiers are preplaced. We investigate the problem of routing the maximum number of connections while maintaining proper power levels. The problem is formulated as a mixed-integer nonlinear program and two-phase hybrid solution approaches employing …


Affinity Chromatography: A Review Of Clinical Applications, David S. Hage Jan 1999

Affinity Chromatography: A Review Of Clinical Applications, David S. Hage

David Hage Publications

Affinity chromatography is a type of liquid chromatography that makes use of biological-like interactions for the separation and specific analysis of sample components. This review describes the basic principles of affinity chromatography and examines its use in the testing of clinical samples, with an emphasis on HPLCbased methods. Some traditional applications of this approach include the use of boronate, lectin, protein A or protein G, and immunoaffinity supports for the direct quantification of solutes. Newer techniques that use antibody-based columns for on- or off-line sample extraction are examined in detail, as are methods that use affinity chromatography in combination with …


Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker Jan 1999

Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker

US Army Corps of Engineers

Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) …