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2001

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Articles 2101 - 2130 of 3030

Full-Text Articles in Physical Sciences and Mathematics

The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik Jan 2001

The Likely Cause Of Extinction Of The Tree Snail Orthalicus Reses Reses (Say), E.A. Forys, A. Quistorff, Craig R. Allen, D.P. Wojcik

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Stock Island tree snail, Orthalicus reses reses, went extinct in its native range in the Florida Keys in 1992. Fortunately, O. r. reses has been introduced elsewhere and further reintroductions are currently planned. Before these reintroductions are implemented, it is important to try and determine which factors were most likely to have caused the decline and extinction. While habitat destruction was probably the ultimate reason why there were so few tree snails, it is likely that an interaction of habitat fragmentation and the invasion of an exotic predator caused the final decline that lead to the extinction in …


Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz Jan 2001

Red Imported Fire Ants: Impact On Biodiversity, Daniel P. Wojcik, Craig R. Allen, Richard J. Brenner, Elizabeth A. Forys, Donald P. Jouvenaz, R. Scott Lutz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The red imported fire ant, Solenopsis invicta Buren (hereafter referred to as imported fire ant), long considered a regional problem, is receiving renewed attention nationwide, with infestations found in Arizona, Maryland, Nevada, New Mexico, and Virginia (Mitchell 1996). Recently, infestations discovered in several regions of California caused great public concern (Brennan 1999, Schrader 1999). Initially, infestations appeared to be isolated in almond groves in Kern County; presumably these infestations originated from bee hives transported interstate for the purpose of pollinating crops. Separately, ornamental plants arriving in Las Vegas, NV, were infested with fire ants, and records showed that the point …


Nonlethal Methods Of Examining Fish Stomach Contents, Jan F. Kamler, Kevin L. Pope Jan 2001

Nonlethal Methods Of Examining Fish Stomach Contents, Jan F. Kamler, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Several nonlethal methods have been developed to determine the stomach contents of fish, including gastroscopes, tubes, stomach suction, stomach flushing, emetics, forceps, and chronic fistulas. By reviewing the literature on this subject, we found that the effectiveness (ability to remove all stomach contents) of the different methods depends on size, age, species of fish, and the size of the food items in the stomach. Overall, various methods of stomach flushing were the most effective method of recovering stomach items from a variety of fishes. Mechanized pressure appeared to be the most efficient method of stomach flushing for most large fishes. …


A Caloric-Based Evaluation Of Diet Indices For Largemouth Bass, Kevin Lee Pope, Michael Lee Brown, Walter Gilbert Duffy, Paul Herbert Michaletz Jan 2001

A Caloric-Based Evaluation Of Diet Indices For Largemouth Bass, Kevin Lee Pope, Michael Lee Brown, Walter Gilbert Duffy, Paul Herbert Michaletz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Selection of methods for quantitative description and assessment of food habits is a concern for trophic investigations. We used diet data for largemouth bass Micropterus salmoides, to compare a caloric-based approach with eight diet indices: percent frequency of occurrence, percent total number, percent total weight, mean relative number, mean relative volume, relative importance index, prey-importance index, and mean stomach fullness. Mean caloric contribution of stomach contents for each prey taxon was used as a standard to compare diet indices. Temporal differences in composition and caloric contents of largemouth bass stomach contents were apparent. Most diet indices provided similar assessments …


Assessment Of Outputs From Smith-Root Model-5.0 Gpp And Model-7.5 Gpp Electrofishers, Kevin L. Pope, Brian E. Van Zee, Michael C. Mayo, Mohammed Rahman Jan 2001

Assessment Of Outputs From Smith-Root Model-5.0 Gpp And Model-7.5 Gpp Electrofishers, Kevin L. Pope, Brian E. Van Zee, Michael C. Mayo, Mohammed Rahman

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We evaluated the outputs from eight Smith-Root electrofishers (two factory-rigged model-5.0 GPP boats, four biologist-rigged model-5.0 GPP boats, and two biologist-rigged model- 7.5 GPP boats), using an oscilloscope to determine the actual waveforms (voltage as a function of time), current, and power produced for various settings. Differences were found in average power outputs among the six model-5.0 GPP electrofishing boats. In terms of average power output, biologist-rigged electrofishing boats using generators and control boxes purchased from Smith-Root were as or more effective than those rigged by Smith-Root. However, factory-rigged boats generally contained additional safety features that should be considered when …


Anglers Tagging And Marking Fish: Provincial And State Fishery Agency Views, Kevin L. Pope Jan 2001

Anglers Tagging And Marking Fish: Provincial And State Fishery Agency Views, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In recent years, the involvement of anglers in fish tagging programs has begun to capture the interest of managers. I conducted a mail survey of provincial and state fishery agencies to discern where anglers could legally tag, mark, or attach telemetry devices to fish. In addition, I documented current provincial and state agency views toward fish tagging or marking by anglers. Anglers were allowed to tag or mark fish in most provinces and states; however, more restrictions were placed on marking and telemetering fish than on tagging. Of the issues covered in this survey, respondents indicated that fish mortality and …


Yellow Jackets (Vespula Spp.) Disperse Trillium (Spp.) Seeds In Eastern North America, Jennifer A. Zettler, Timonthy P. Spira, Craig R. Allen Jan 2001

Yellow Jackets (Vespula Spp.) Disperse Trillium (Spp.) Seeds In Eastern North America, Jennifer A. Zettler, Timonthy P. Spira, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Approximately 70 plant families worldwide have ant-dispersed seeds (myrmecochory). In this putative ant-plant mutualism, ants are attracted to and disperse seeds that have a lipid-rich elaiosome. We observed yellow jackets (Vespula spp.) dispersing seeds of three elaiosome-bearing species-Trillium cuneatum, T. undulatum and T catesbaei-in the Blue Ridge Mountains of North Carolina and South Carolina. Moreover, we estimated the mean distance yellow jackets dispersed seeds of T. cuneatum by placing intact fruits on index cards and recovering dispersed seeds on sheets placed on the ground surface. Of the seeds presented, 41% were recovered and the average dispersal distance …


Mcnair Research Journal Jan 2001

Mcnair Research Journal

Georgia Southern University McNair Scholars Journal

  • Comparing Aerobic And Anaerobic Physical Activity Utilizing A Three Site Skinfold Shawnae Allen


  • Theory, laser light, and the adiabatic approximation Shannon Anderson


  • Perceptions Of Elementary Gifted Students Kalesha Brown


  • Population Structure Of The Blacklegged Tick, Ixodes Scapularis, In Eastern United States Using Microsatellite DNA Markers Shahnjayla K. Connors


  • The Growing Minority: A Study Of Local Reactions To The Increasing Latino Population In Southeast Georgia Miranda Davis


  • Assessing The Economic Impact Of The School Information Technology At Georgia Southern Mary Dowling


  • The Desegregation of Law Enforcement in a Rural Community: Statesboro, Georgia Ebony Starla Halliburton


  • Understanding The Racial Gap In Healthcare: …


Field-Scale Electrical Conductivity Mapping For Delineating Soil Condition, Cinthia K. Johnson, John Doran, Harold R. Duke, Brian J. Wienhold, Kent M. Eskridge, John F. Shanahan Jan 2001

Field-Scale Electrical Conductivity Mapping For Delineating Soil Condition, Cinthia K. Johnson, John Doran, Harold R. Duke, Brian J. Wienhold, Kent M. Eskridge, John F. Shanahan

Department of Statistics: Faculty Publications

Traditional sampling methods are inadequate for assessing the interrelated physical, chemical, and biological soil properties responsible for variations in agronomic yield and ecological potentials across a landscape. Recent advances in computers, global positioning systems, and large-scale sensors offer new opportunities for mapping heterogeneous patterns in soil condition. We evaluated field-scale apparent electrical conductivity (ECa) mapping for delineating soil properties correlated with productivity and ecological properties. A contiguous section of farmland (250 ha), managed as eight fields in a no-till winter wheat (Triticum aestivum L.)–corn (Zea mays L.)–millet (Panicum miliaceum L.)–fallow rotation, was ECa mapped (≈0- to …


Manifest Characterization And Testing For Certain Latent Properties, A. Yuan, Bertrand S. Clarke Jan 2001

Manifest Characterization And Testing For Certain Latent Properties, A. Yuan, Bertrand S. Clarke

Department of Statistics: Faculty Publications

Work due to Junker and more recently due to Junker and Ellis characterized desired latent properties of an educational testing procedure in terms of a collection of other manifest properties. This is important because one can only propose tests for manifest quantities, not latent ones. Here, we complete the conversion of a pair of latent properties to equivalent conditions in terms of four manifest quantities and identify a general method for producing tests for manifest properties.


A Critical Look At Self-Dual Codes, Judy L. Walker Jan 2001

A Critical Look At Self-Dual Codes, Judy L. Walker

Department of Mathematics: Faculty Publications

We investigate self-dual codes from a structural point of view. In particular, we study properties of critical indecomposable codes which appear in the spectrum of a self-dual code. As an application of the results we obtain, we revisit the study of self-dual codes of dimension at most 10.

In the late 1950’s, Slepian [4] became the first to take an abstract approach to the study of error-correcting codes. He introduced a structure theory for binary linear codes, developing in particular the idea of an indecomposable code; that is, a code which is not isomorphic to a nontrivial direct sum of …


On The Evolution Of Probability-Weighting Function And Its Impact On Gambling, Steven Li, Yun Hsing Cheung Jan 2001

On The Evolution Of Probability-Weighting Function And Its Impact On Gambling, Steven Li, Yun Hsing Cheung

Research outputs pre 2011

It is well known that individuals treat losses and gains differently and there exists non-linearity in probability. The asymmetry between gains and losses is highlighted by the reflection effect. The non-linearity in probability is described by the curvature of the probability-weighting function. This paper studies the evolution of the probability-weighting function. It is assumed that the probability weighting for an individual follows a mean-reverting stochastic process. The Monte Carlo simulation technique is employed to study the evolution of the weighting function. The evolution of the probability- weighting function implies that an individual does not treat gains or losses consistently over …


Calculation Of The Potential And Electric Flux Lines For Parallel Plate Capacitors With Symmetrically Placed Equal Lengths By Using The Method Of Conformal Mapping, Erhan Albayrak Jan 2001

Calculation Of The Potential And Electric Flux Lines For Parallel Plate Capacitors With Symmetrically Placed Equal Lengths By Using The Method Of Conformal Mapping, Erhan Albayrak

Turkish Journal of Physics

The classical problem of the parallel-plate capacitors has been investigated by a number of authors, including Love [1], Langton [2] and Lin [3]. In this paper, the exact equipotentials and electric flux lines of symmetrically placed two thin conducting plates are obtained using the Schwarz- Cristoffel transformation and the method of conformal mapping. The coordinates x , y in the z-plane corresponding to the constant electric flux lines and equipotential lines are obtained after very detailed and cumbersome calculations. The complete field distribution is given by constructing the family of lines of electric flux and equipotential.


Optical Transmission Measurements On Glow-Discharge Amorphous Silicon Nitride Films, İlker Ay, Hüseyi̇n Tolunay Jan 2001

Optical Transmission Measurements On Glow-Discharge Amorphous Silicon Nitride Films, İlker Ay, Hüseyi̇n Tolunay

Turkish Journal of Physics

Hydrogenated amorphous silicon nitride films have been prepared by the glow-discharge decomposition of ammonia/silane gas mixture. From optical transmission measurements in the wavelength range from 400 nm to 1100 nm refractive indices absorption coefficients and optical Tauc gaps of the films have been obtained. A systematic investigation of optical parameters has been carried out as a function of the nitrogen content of samples.


Study Of Slip Systems In Epidote Single Crystal, Salah-Ud Din, Munnawar Ahmad, Shahzad Chishti Jan 2001

Study Of Slip Systems In Epidote Single Crystal, Salah-Ud Din, Munnawar Ahmad, Shahzad Chishti

Turkish Journal of Physics

Measurements of microhardness anisotropy by Knoop diamond indentations on the prismatic (100) planes of epidote crystals, point group 2/m and space group P21/m, show that microhardness is determined by crystallographic slip on the (100) systems. Microhardness anisotropy is explained in terms of the effective resolved shear stress distribution in these slip systems.


Computation Of Overlap, Kinetic And Nuclear Attraction Integrals By A Novel Method, Gökhan Budak, Abdulhali̇k Karabulut, Lütfü Demi̇r, Nagi̇f Sefteroğlu Nabi̇yev, Yusuf Şahi̇n Jan 2001

Computation Of Overlap, Kinetic And Nuclear Attraction Integrals By A Novel Method, Gökhan Budak, Abdulhali̇k Karabulut, Lütfü Demi̇r, Nagi̇f Sefteroğlu Nabi̇yev, Yusuf Şahi̇n

Turkish Journal of Physics

A new way of computing overlap, kinetic and nuclear attraction integrals over Slater functions by means of optimized Gaussian expansion is proposed. This article is concerned with the construction of the general algorithm for evaluating the three integrals. These integral formulae presented in the form of a series whose terms are the analytical function of inter-atomic distances. In the present method, unlike many other popular methods, the numerical integration procedure is unnecessary since it does not contain the incomplete gamma function. The present scheme has been programmed in standard Fortran-77 and tested for various orbitals. The result of the calculation …


Some String Cosmological Models In Cylindrically Symmetric Inhomogeneous Universe, Hüsnü Baysal, İlhami̇ Yavuz, İsmai̇l Tarhan, Uğur Camci, İshan Yilmaz Jan 2001

Some String Cosmological Models In Cylindrically Symmetric Inhomogeneous Universe, Hüsnü Baysal, İlhami̇ Yavuz, İsmai̇l Tarhan, Uğur Camci, İshan Yilmaz

Turkish Journal of Physics

The aim of this paper is to investigate the behavior of a string in the cylindrically symmetric inhomogeneous cosmological model. It has been assumed that expansion \theta in the model is proportional to \sigma^1_1 of the eigenvalue of the shear tensor \sigma^{\mu}_{\nu}. Also, various physical and geometrical properties of the model have been discussed.


Lattice Dynamical Calculations For The Co-Fe Alloys, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇ Jan 2001

Lattice Dynamical Calculations For The Co-Fe Alloys, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇

Turkish Journal of Physics

Lattice dynamical calculations are performed on Co_{0.92}-Fe_{0.08} alloy with fcc structure. The de Launay Angular force (DAF) model is used to represent the ion-ion intreactions, and the long-range ion-electron interactions are accounted for along the lines of the Sharma-Joshi scheme. The frequency distribution and the lattice specific heat are also computed for the studied alloys. The present theoretical results are in reasonable agreement with the available experimental data.


Second Order Elastic Constants And Some Thermoelastic Properties Of Alkali Halides Using Woodcock Potential, Harun Reşi̇t Yazar, Sedat Ağan, Kemal Çolakoğlu Jan 2001

Second Order Elastic Constants And Some Thermoelastic Properties Of Alkali Halides Using Woodcock Potential, Harun Reşi̇t Yazar, Sedat Ağan, Kemal Çolakoğlu

Turkish Journal of Physics

Second Order Elastic Constants (S.O.E.C) of NaCl-type crystals have been calculated using the Woodcock potential. Short-range repulsive interactions have been included up to second-nearest neighbors. This potential form represents the composite form of the inverse power dependence and exponential dependence of the repulsive energy on interionic distance. Some thermoelastic and thermodynamic properties such as Anderson-Grüneisen parameters \delta _{T}, and \delta _{S}, Volume thermal expansion coefficient \beta and Grüneisen gama \gamma _{G} have been calculated in terms of calculated values of S.O.E.C and Third Order Elastic Constant ( T.O.E.C).


Computational Study For The Structural Change Of The System Cdte_{1-X} S_X Thin Film, Emad Khdayer Al-Shakarchi Jan 2001

Computational Study For The Structural Change Of The System Cdte_{1-X} S_X Thin Film, Emad Khdayer Al-Shakarchi

Turkish Journal of Physics

Polycrystalline thin film of the graded system CdTe_{1-x}S_{x} for x=0,0.1,\ldots,1 are prepared by using thermal evaporation technique deposited on the glass substrate with an average thickness 3000 Å for each individual value of x . XRD technique is used with the aid of a computational program to study the phase change from cubic zinc blend structure to hexagonal wurtzite with an inversion point related to the x-value. It is found that x=0.1 gives us an inversion point in the structural change from cubic to hexagonal phase.


The Lattice Dynamics And The Elastic Behaviour Of Fcc And Bcc Ba, Yasemi̇n Özteki̇n Çi̇ftçi̇, Kemal Çolakoğlu Jan 2001

The Lattice Dynamics And The Elastic Behaviour Of Fcc And Bcc Ba, Yasemi̇n Özteki̇n Çi̇ftçi̇, Kemal Çolakoğlu

Turkish Journal of Physics

The two-body pairwise E.G.E.P. (Extended Generalized Exponantial Potential) type Morse potential and volume dependent energy are assumed to represent the total energy of the Ba crystal. The parametrized potential is used to calculate the second- and third-order elastic constants C_{ij} and C_{ijk}, pressure derivatives of bulk moduli and Grüneisen parameter \gamma . The phonon frequencies are also computed and plotted. The obtained results are compared with available experimental data and, in general, the agreement is good.


Iba-1 Calculations Of E2/M1 Mixing Ratios And Quadrupole Moments In ^{154}Gd, Mehmet Baylan Jan 2001

Iba-1 Calculations Of E2/M1 Mixing Ratios And Quadrupole Moments In ^{154}Gd, Mehmet Baylan

Turkish Journal of Physics

In this study the Interacting Boson Approximation is applied in its basic form (IBA-1) to the calculation of gamma-ray E2/M1 multipole mixing ratios and quadrupole moments [Q( 2^{+} )] of electromagnetic transitions in ^{154}Gd. The numerical results obtained for ^{154}Gd are in reasanably good agreement with previous experimental and theoretical values.


Built-In Potential Measurements In A-Si:H P-I-N Solar Cells, Ruhi̇ Kaplan, Bengü Kaplan Jan 2001

Built-In Potential Measurements In A-Si:H P-I-N Solar Cells, Ruhi̇ Kaplan, Bengü Kaplan

Turkish Journal of Physics

We have measured the open-circuit voltage V_{oc} and the short-circuit current density J_{sc} of amorphous silicon (a-Si:H) p-i-n solar cells deposited by radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) at different monochromatic illuminations, and temperatures. From the measurements, the built-in potential V_{bi} was determined by using two different methods: activation energy and differential temperature. The results from both methods were analyzed and compared as a function of excitation wavelength. It was observed that there is good agreement between the two methods. We found that V_{bi} increases until about 650 nm, and then decreases with increasing wavelength. This behaviour is explained and …


Space Charge Limited Current At High Fields In Al-Ge-Al Surface Barrier Devices, A. I. Mukolu Jan 2001

Space Charge Limited Current At High Fields In Al-Ge-Al Surface Barrier Devices, A. I. Mukolu

Turkish Journal of Physics

The current-voltage (I-V) characteristics of Aluminium-Germanium-Aluminium (Al-Ge-Al) surface barrier devices at different fields (


Coproduct Of Su_{Q} (2), Coherent States And Four Point Function With Logarithmic Regge Trajectories, M. Arik, Ayşe Peker-Dobie Jan 2001

Coproduct Of Su_{Q} (2), Coherent States And Four Point Function With Logarithmic Regge Trajectories, M. Arik, Ayşe Peker-Dobie

Turkish Journal of Physics

The representation of the operators belonging to a 2 \times 2 SU_q (2) matrix yield a Hilbert space H. The coproducts of these operators define a Hilbert space H^{(2)} isomorphic to H and canonically embedded in H \otimes H. The four-point function obtained by taking the scalar product of the ground state of H^{(2)} with the coherent states in H \otimes H is uniquely defined, is meromorphic and has Regge behaviour.


Null String In Curved Backgrounds, Sergey Nikolaevich Roshchupkin Jan 2001

Null String In Curved Backgrounds, Sergey Nikolaevich Roshchupkin

Turkish Journal of Physics

We consider null string in curved backgrounds. Some exact solutions of the classical equations of motion and of the constraints for the null string in a large class of cosmological backgrounds are found.


On The Evaluation Of Determinantal Wave Functions In Open-Shell Hartree-Fock Theory, I. I. Guseinov, Ramazan Demi̇r Jan 2001

On The Evaluation Of Determinantal Wave Functions In Open-Shell Hartree-Fock Theory, I. I. Guseinov, Ramazan Demi̇r

Turkish Journal of Physics

Slater method is modified for the evaluation of determinantal wave functions appearing in open-shell Hartree-Fock (HF) theory [1]. Using modified Slater method we have calculated, as an example, the orbital energies and the wave functions of terms obtained from the electronic configuration of a ground state of an N-atom system in the Hartree-Fock-Roothaan (HFR) approximation. The modified determinantal method introduced in this paper can be of considerable help and importance in the simplification and calculation of atomic and molecular electronic structure.


Excitation Plus Ionization In Electron-Atom Collisions To He^{+} (N=2): (E,2e), (E, E\Gamma ) And (E, 2e\Gamma ) Studies, Mevlut Dogan, Albert Crowe Jan 2001

Excitation Plus Ionization In Electron-Atom Collisions To He^{+} (N=2): (E,2e), (E, E\Gamma ) And (E, 2e\Gamma ) Studies, Mevlut Dogan, Albert Crowe

Turkish Journal of Physics

Simultaneous excitation-ionization of helium atoms by electron impact is observed by the coincidence detection of the outgoing particles. The relationship between (e,2e), (e,e\gamma ) and (e,2e\gamma ) experiments is discussed.


Covariant Two Fermion Equations With Anomalous Moments, Ahmet Turan Alan, Z. Zekeri̇ya Aydin, Nuretti̇n Karagöz, Ali̇ Ulvi̇ Yilmazer Jan 2001

Covariant Two Fermion Equations With Anomalous Moments, Ahmet Turan Alan, Z. Zekeri̇ya Aydin, Nuretti̇n Karagöz, Ali̇ Ulvi̇ Yilmazer

Turkish Journal of Physics

We derive covariant equations for two-fermion systems, taking into account the anomalous magnetic moments of the particles.


Double Transition Effect In Anderson Transition, Hüseyi̇n Aktaş Jan 2001

Double Transition Effect In Anderson Transition, Hüseyi̇n Aktaş

Turkish Journal of Physics

In this work we have studied the electronic mobility \mu within a completely disordered lattice system by using the strong interatomic hopping potential V(r) = ( - {\frac{{r}}{{a_{o}} }}) \exp( - r / a_{o} ) for site representation of the Hamiltonian. It is shown that a metallic system of a completely disordered lattice first goes insulating and then goes back to metallic again at higher atomic density \rho .