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2007

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Termite Resource Partitioning Related To Log Diameter, Deborah A. Waller Jan 2007

Termite Resource Partitioning Related To Log Diameter, Deborah A. Waller

Biological Sciences Faculty Publications

The termites Reticuliterines virginicus and R. flavipes are sympatric in forests along the eastern United States from Florida to Maryland. These congeners construct subterranean nests, forage on surface and buried wood, and appear to have very similar ecological requirements. In the present study, I examined host-wood selection by these species in a coastal forest over two years. Logs inhabited by R. virginicus had significantly greater diameters than those used by R. flavipes. It is not known whether this pattern resulted from species-specific differences in preference for host size or competition for preferred logs. Host-wood temperature did not differ for …

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Acoustic Emission Detection And Prediction Of Fatigue Crack Propagation In Composite Patch Repairs Using Neural Networks, Navdeep Singh, Navrag Singh, Anthony Chukwujekwu Okafor Jan 2007

Acoustic Emission Detection And Prediction Of Fatigue Crack Propagation In Composite Patch Repairs Using Neural Networks, Navdeep Singh, Navrag Singh, Anthony Chukwujekwu Okafor

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An aircraft is subjected to severe structural and aerodynamic loads during its service life. These loads can cause damage or weakening of the structure especially for aging military and civilian aircraft, thereby affecting its load carrying capabilities. Hence composite patch repairs are increasingly used to repair damaged aircraft metallic structures to restore its structural efficiency. This paper presents the results of Acoustic Emission (AE) monitoring of crack propagation in 2024-T3 Clad aluminum panels repaired with adhesively bonded octagonal, single sided boron/epoxy composite patch under tension-tension fatigue loading. Crack propagation gages were used to monitor crack initiation. The identified AE sensor …

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Simple Penning Ion Source For Laboratory Research And Development Applications, Joshua L. Rovey, Brandon P. Ruzic, Thomas J. Houlahan Jan 2007

Simple Penning Ion Source For Laboratory Research And Development Applications, Joshua L. Rovey, Brandon P. Ruzic, Thomas J. Houlahan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A simple Penning ion generator (PIG) that can be easily fabricated with simple machining skills and standard laboratory accessories is described. The PIG source uses an iron cathode body, samarium cobalt permanent magnet, stainless steel anode, and iron cathode faceplate to generate a plasma discharge that yields a continuous 1 mA beam of positively charged hydrogen ions at 1 mTorr of pressure. This operating condition requires 5.4 kV and 32.4 W of power. Operation with helium is similar to hydrogen. The ion source is being designed and investigated for use in a sealed-tube neutron generator; however, this ion source is …

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Detection Of Mitochondrial Insertions In The Nucleus (Numts) Of Pleistocene And Modern Muskoxen, Sergios-Orestis Kolokotronis, Ross De Macphee, Alex D. Greenwood Jan 2007

Detection Of Mitochondrial Insertions In The Nucleus (Numts) Of Pleistocene And Modern Muskoxen, Sergios-Orestis Kolokotronis, Ross De Macphee, Alex D. Greenwood

Biological Sciences Faculty Publications

Background: Nuclear insertions of mitochondrial sequences (NuMts) have been identified in a wide variety of organisms. Trafficking of genetic material from the mitochondria to the nucleus has occurred frequently during mammalian evolution and can lead to the production of a large pool of sequences with varying degrees of homology to organellar mitochondrial DNA (mtDNA) sequences. This presents both opportunities and challenges for forensics, population genetics, evolutionary genetics, conservation biology and the study of DNA from ancient samples. Here we present a case in which difficulties in ascertaining the organellar mtDNA sequence from modern samples hindered their comparison to ancient DNA …

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Cybercraft: Protecting Electronic Systems With Lightweight Agents, Daniel R. Karrels, Gilbert L. Peterson Jan 2007

Cybercraft: Protecting Electronic Systems With Lightweight Agents, Daniel R. Karrels, Gilbert L. Peterson

Faculty Publications

The United States military is seeking new and innovative methods for securing and maintaining its computing and network resources locally and world-wide. This document presents a work-in-progress research thrust toward building a system capable of meeting many of the US military’s network security and sustainment requirements. The system is based on a Distributed Multi-Agent System (DMAS), that is secure, small, and scalable to the large networks found in the military. It relies on a staged agent architecture capable of dynamic configuration to support changing mission environments. These agents are combined into Hierarchical Peer-to-Peer (HP2P) networks to provide scalable solutions. They …

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Co2 Control Of Trichodesmium N-2 Fixation, Photosynthesis, Growth Rates, And Elemental Ratios: Implications For Past, Present, And Future Ocean Biogeochemistry, D. A. Hutchins, F.-X. Fu, Y. Zhang, M. E. Warner, Y. Feng, K. Portune, P. W. Bernhardt, M. R. Mulholland Jan 2007

Co2 Control Of Trichodesmium N-2 Fixation, Photosynthesis, Growth Rates, And Elemental Ratios: Implications For Past, Present, And Future Ocean Biogeochemistry, D. A. Hutchins, F.-X. Fu, Y. Zhang, M. E. Warner, Y. Feng, K. Portune, P. W. Bernhardt, M. R. Mulholland

OES Faculty Publications

Diazotrophic marine cyanobacteria in the genus Trichodesmium contribute a large fraction of the new nitrogen entering the oligotrophic oceans, but little is known about how they respond to shifts in global change variables such as carbon dioxide (CO2) and temperature. We compared Trichodesmium dinitrogen (N2) and CO2 fixation rates during steady-state growth under past, current, and future CO2 scenarios, and at two relevant temperatures. At projected CO2 levels of year 2100 (76 Pa, 750 ppm), N2 fixation rates of Pacific and Atlantic isolates increased 35-100%, and CO2 fixation rates increased 15-128% …

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Application Of Maldis-Ms To Identification Of Phytoplankton In Ballast Water, Dana Woodruff, Karen L. Wahl, Nancy B. Valentine, Fred Dobbs Jan 2007

Application Of Maldis-Ms To Identification Of Phytoplankton In Ballast Water, Dana Woodruff, Karen L. Wahl, Nancy B. Valentine, Fred Dobbs

OES Faculty Publications

Non-native invasive species are increasingly evident in marine and estuarine environments, largely because of the intake and release of ballast water from sea vessels. Innovative methods are needed to quickly and accurately detect and speciate non-native and/or harmful phytoplankton in ballast water. Recent advances in ionization techniques such as matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) have allowed detection of intact biomolecules within ballast samples. Statistically-based algorithms are used to discern "fingerprints" of phytoplankton species and to discern individual species from mixtures. MALDI-MS is particularly attractive for field applications because of the speed of analysis, minimal liquids/consumables required, and femtomole (10-15) …

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The Fate Of Nitrogren Fixed By Diazotrophs In The Ocean, Margaret R. Mulholland Jan 2007

The Fate Of Nitrogren Fixed By Diazotrophs In The Ocean, Margaret R. Mulholland

OES Faculty Publications

While we now know that N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N2 fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or does it contribute primarily to bacterial productivity and respiration in the euphotic zone? For Trichodesmium, the diazotroph we know the most about, the transfer of recently fixed N2 (and C) appears …

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Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann Jan 2007

Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann

OES Faculty Publications

The primary objective of this research is to investigate phytoplankton community response to variations in physical forcing and biological processes in the Cold Tongue region of the equatorial Pacific Ocean at 0N, 140W. This research objective was addressed using a one-dimensional multicomponent lower trophic level ecosystem model that includes detailed algal physiology, such as spectrally-dependent photosynthetic processes and iron limitation on algal growth. The ecosystem model is forced by a one-year (1992) time series of spectrally-dependent light, temperature, and water column mixing obtained from a Tropical Atmosphere-Ocean (TAO) Array mooring. Autotrophic growth is represented by five algal groups, which have …

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The Emerging Culture Of Health Care: From Horizontal Violence To True Collaboration, Debra Gerardi, Mary Kunes Connell Jan 2007

The Emerging Culture Of Health Care: From Horizontal Violence To True Collaboration, Debra Gerardi, Mary Kunes Connell

Faculty Scholarship

No abstract provided.

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Is It Necessary To Consider Obesity When Constructing Norms For Hemoglobin Or When Screening For Anemia Using Hemoglobin Levels?, Fahaid H. Al-Hashem Jan 2007

Is It Necessary To Consider Obesity When Constructing Norms For Hemoglobin Or When Screening For Anemia Using Hemoglobin Levels?, Fahaid H. Al-Hashem

Saudi Medical Journal

OBJECTIVE: To assess the relationship of total adiposity and abdominal adiposity on hemoglobin levels in Saudi nonpregnant women. METHODS: We carried out this cross-sectional study during winter of 2002 (from January to March) in and around Abha city, Kingdom of Saudi Arabia. Included in the study were 530 non-pregnant women between the age of 18-65 years. Body weight was measured using an Avery Beam weighing scale, while height was measured using a stadiometer and waist circumference using a fiberglass. Hemoglobin levels were estimated using cyanmethemoglobin method. Total obesity was defined as body mass index (BMI) >/=30 and abdominal obesity as …

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Identification And Characterization Of A New Tubulin-Binding, Susan L. Mooberry, Kimberly N. Weiderhold, Sivanesan Dakshanamurthy, Ernest Hamel, Edith J. Banner, Anastasia Kharlamova, Jonathan Hempel, John T. Gupton, Milton L. Brown Jan 2007

Identification And Characterization Of A New Tubulin-Binding, Susan L. Mooberry, Kimberly N. Weiderhold, Sivanesan Dakshanamurthy, Ernest Hamel, Edith J. Banner, Anastasia Kharlamova, Jonathan Hempel, John T. Gupton, Milton L. Brown

Chemistry Faculty Publications

We studied the mechanism of action of 3,5-dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester (JG-03-14) and found that it is a potent microtubule depolymerizer. JG-03-14 caused a dose-dependent loss of cellular microtubules, formation of aberrant mitotic spindles, accumulation of cells in the G2/M phase of the cell cycle, and Bcl-2 phosphorylation. These events culminated in the initiation of apoptosis, as evidenced by the caspase 3-dependent cleavage of poly(ADP-ribose) polymerase (PARP). JG-03-14 has antiproliferative activity against a wide range of cancer cell lines, with an average IC50 value of 62 nM, and it is a poor substrate for transport …

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Antiferromagnetic Transition In Thermally Evaporated Manganese-Vanadium Alloys, F. Boakye Jan 2007

Antiferromagnetic Transition In Thermally Evaporated Manganese-Vanadium Alloys, F. Boakye

Turkish Journal of Physics

Antiferromagnetic transition in thermally evaporated Mn-V alloys has been studied using resistivity-temperature measurements from 300 to 1.4 K. Resistivity-temperature behaviour typical of bulk \alpha -Mn rich specimen is obtained with 0.05 at % V in Mn. The Néel point is shifted to 86 \pm 1 K from the value of 90 \pm 1 K known for pure \alpha -Mn. The Néel point is shifted further to lower values as the concentration of V in Mn increases. Below the temperature corresponding to the low temperature resistivity minimum, the resistivity obeys a T^2 law, suggesting that vanadium impurities in the manganese film …

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Eddy Correlation Measurements Of The Air/Sea Flux Of Dimethylsulfide Over The North Pacific Ocean, Christa A. Marandino, Warren J. De Bruyn, Scott D. Miller, Eric S. Saltzman Jan 2007

Eddy Correlation Measurements Of The Air/Sea Flux Of Dimethylsulfide Over The North Pacific Ocean, Christa A. Marandino, Warren J. De Bruyn, Scott D. Miller, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Shipboard measurements of air/sea fluxes and sea surface concentrations of dimethylsulfide (DMS) were made over the tropical and midlatitude North Pacific Ocean. Atmospheric pressure chemical ionization mass spectrometry was used to measure DMS levels in ambient air and in air equilibrated with surface seawater drawn from a depth of 5 m. Air/sea fluxes were obtained using eddy covariance. Corrections and uncertainties involved in the calculation of fluxes from shipboard data are discussed. The surface ocean DMS concentrations measured during this study ranged from 1 to 10 nM, and atmospheric mixing ratios ranged from 20 to 1000 ppt. Air/sea fluxes ranged …

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Flavin Charge Transfer Transitions Assist Dna Photolyase Electron Transfer, Spiros S. Skourtis, Tatiana Prytkova, David Beratan Jan 2007

Flavin Charge Transfer Transitions Assist Dna Photolyase Electron Transfer, Spiros S. Skourtis, Tatiana Prytkova, David Beratan

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This contribution describes molecular dynamics, semi-empirical and ab-initio studies of the primary photo-induced electron transfer reaction in DNA photolyase. DNA photolyases are FADH−-containing proteins that repair UV-damaged DNA by photo-induced electron transfer. A DNA photolyase recognizes and binds to cyclobutatne pyrimidine dimer lesions of DNA. The protein repairs a bound lesion by transferring an electron to the lesion from FADH−, upon photo-excitation of FADH− with 350–450 nm light. We compute the lowest singlet excited states of FADH− in DNA photolyase using INDO/S configuration interaction, time-dependent density-functional, and time-dependent Hartree-Fock methods. The calculations identify the lowest singlet excited state of FADH− …

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Above The Law? The Constitutionality Of The Ministerial Exemption From Antidiscrimination Law, Caroline Mala Corbin Jan 2007

Above The Law? The Constitutionality Of The Ministerial Exemption From Antidiscrimination Law, Caroline Mala Corbin

Articles

No abstract provided.

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A Hidden History Of Affirmative Obligation, Patrick O. Gudridge Jan 2007

A Hidden History Of Affirmative Obligation, Patrick O. Gudridge

Articles

No abstract provided.

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In Search Of Regulatory Equilibrium, Lili Levi Jan 2007

In Search Of Regulatory Equilibrium, Lili Levi

Articles

No abstract provided.

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Re-Conceptualizing Poverty Law Clinical Curriculum And Legal Services Practice: The Need For Generalists, Jonel Newman Jan 2007

Re-Conceptualizing Poverty Law Clinical Curriculum And Legal Services Practice: The Need For Generalists, Jonel Newman

Articles

No abstract provided.

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"Unchain The Children": Gault, Therapeutic Jurisprudence, And Shackling, Bernard P. Perlmutter Jan 2007

"Unchain The Children": Gault, Therapeutic Jurisprudence, And Shackling, Bernard P. Perlmutter

Articles

No abstract provided.

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Divorce Reform: Rights Protections In The New Swaziland, Tamar Ezer, Aisha Glasford, Elizabeth Hollander, Lakeisha Poole, Grant Rabenn, Alexandria Tindall Jan 2007

Divorce Reform: Rights Protections In The New Swaziland, Tamar Ezer, Aisha Glasford, Elizabeth Hollander, Lakeisha Poole, Grant Rabenn, Alexandria Tindall

Articles

No abstract provided.

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Lincoln And Chief Justice Taney: Slavery, Secession, And The President's War Powers, James F. Simon Jan 2007

Lincoln And Chief Justice Taney: Slavery, Secession, And The President's War Powers, James F. Simon

Books

The clashes between President Abraham Lincoln and Chief Justice Roger B. Taney over slavery, secession, and the president's constitutional war powers went to the heart of Lincoln's presidency. James Simon, author of the acclaimed What Kind of Nation, brings to vivid life the passionate struggle during the worst crisis in the nation's history, the Civil War. The issues that underlaid that crisis -- race, states' rights, and the president's wartime authority -- resonate today in the nation's political debate.

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Finding Interior Peace In The Ordinary Practice Of Law: Wisdom From The Spiritual Tradition Of St. Teresa Of Avila, Jacqueline Nolan-Haley Jan 2007

Finding Interior Peace In The Ordinary Practice Of Law: Wisdom From The Spiritual Tradition Of St. Teresa Of Avila, Jacqueline Nolan-Haley

Faculty Scholarship

No abstract provided.

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Latino Inter-Ethnic Employment Discrimination And The Diversity Defense, Tanya K. Hernandez Jan 2007

Latino Inter-Ethnic Employment Discrimination And The Diversity Defense, Tanya K. Hernandez

Faculty Scholarship

With the growing racial and ethnic diversity of the U.S. population and workforce, scholars have begun to address the ways in which coalition building across groups not only will continue to be necessary but also will become even more complex. Recent scholarship has focused on analyzing how best to promote effective coalition building. Thus far, scholars have not examined what that growing racial and ethnic diversity will mean in the context of individual racial and ethnic discrimination claims. What will antidiscrimination litigation look like when all the parties involved are non-White but nonetheless plaintiffs allege that a racial hierarchy exists …

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Climate Change And The Clean Air Act, Lisa Heinzerling Jan 2007

Climate Change And The Clean Air Act, Lisa Heinzerling

Georgetown Law Faculty Publications and Other Works

In Massachusetts v. EPA, petitioners - twelve states, three cities, an American territory, and numerous health and environmental groups - have asked the Supreme Court to hold that the Clean Air Act gives EPA the power to regulate greenhouse gas emissions from motor vehicles and that EPA may not decline to exercise this power based on statutorily irrelevant factors. The problem petitioners ultimately seek to address - climate change - is unique in its scope and complexity. But the legal issues before the Court in Massachusetts v. EPA are neither particularly grand nor particularly complex. They are the kinds of …

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Environmental Law After Katrina: Reforming Environmental Law By Reforming Environmental Lawmaking, Richard J. Lazarus Jan 2007

Environmental Law After Katrina: Reforming Environmental Law By Reforming Environmental Lawmaking, Richard J. Lazarus

Georgetown Law Faculty Publications and Other Works

Hurricane Katrina's overriding lesson for environmental law is no less than our environmental lawmaking institutions require fundamental reformation. Otherwise, the nation's tragic failure not only to enact laws that anticipate the obvious risks presented to the Gulf Region by hurricanes, but perversely to increase those risks by destroying the ecosystem's natural protections, will inevitably be repeated with even more devastating results.

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Physical Properties Of (Li_2o)_{0.40}(Fe_2o_3)_{0.05-X}(P_2o_5)_{0.55}: (Ag_2o)_X Glasses, K. Sambasiva Rao, N. Krishna Mohan, Nalluri Veeraiah Jan 2007

Physical Properties Of (Li_2o)_{0.40}(Fe_2o_3)_{0.05-X}(P_2o_5)_{0.55}: (Ag_2o)_X Glasses, K. Sambasiva Rao, N. Krishna Mohan, Nalluri Veeraiah

Turkish Journal of Physics

Li_2O-Fe_2O_3-P_2O_5 glasses containing small concentrations of Ag_2O from 0 to 2 mol% were prepared. Samples are characterized by X-ray diffraction and scanning electron microscope techniques. A number of studies viz., chemical durability, dielectric studies (constant \varepsilon', loss tan \delta, a.c. conductivity \sigma_{ac} over a range of frequency and temperature), spectroscopic (infrared, optical absorption ESR spectra) and magnetic susceptibility studies of these glasses, have been carried out. The interesting variations observed in all these properties with the concentration of Ag^{+} ions have been analyzed in the light of different oxidation states and environment of iron ions in the glass network.

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Infrared Analysis And Physical Properties Studies Of B_2o_3 · Cao · Zno · Tio_2 Glass System, M. Gabr, Karam Abdel-Ati Ali, Ahmed Gamal El-Din Mostafa Jan 2007

Infrared Analysis And Physical Properties Studies Of B_2o_3 · Cao · Zno · Tio_2 Glass System, M. Gabr, Karam Abdel-Ati Ali, Ahmed Gamal El-Din Mostafa

Turkish Journal of Physics

The glass system having (B_2O_3)_{0.60}(CaO)_{0.25}(ZnO)_{0.15-x} (TiO_2)_x, where x = 0.0, 0.025, 0.05,..., 0.15, was investigated using infrared spectroscopy, differential thermal analysis, density, magnetic susceptibility and dc electrical conductivity. The obtained IR results showed that most titanium ions exist as network former while most zinc ions exist as network modifier but boron ions appeared in different structural groups. As titanium oxide was gradually increased to 10 mol%, the glass stability, density and magnetic susceptibility increased, while the molar volume and dc electrical activation energy decreased. When titanium oxide increased from 10 to 15 mol%, the measured and the calculated properties tend …

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Bianchi Type Vi_1 Viscous Fluid Cosmological Model In Wesson´S Theory Of Gravitation, G. S. Khadekar, G. R. Avachar Jan 2007

Bianchi Type Vi_1 Viscous Fluid Cosmological Model In Wesson´S Theory Of Gravitation, G. S. Khadekar, G. R. Avachar

Turkish Journal of Physics

Field equations of a scale invariant theory of gravitation proposed by Wesson [1, 2] are obtained in the presence of viscous fluid with the aid of Bianchi type VI_h space-time with the time dependent gauge function (Dirac gauge). It is found that Bianchi type VI_h (h = 1) space-time with viscous fluid is feasible in this theory, whereas Bianchi type VI_h (h = -1, 0) space-times are not feasible in this theory, even in the presence of viscosity. For the feasible case, by assuming a relation connecting viscosity and metric coefficient, we have obtained a nonsingular-radiating model. We have discussed …

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The Fluctuation Theory And Gravitational Galaxy Clustering, Sajad Masood, Shakeel A. Simnani, Manzoor A. Malik Jan 2007

The Fluctuation Theory And Gravitational Galaxy Clustering, Sajad Masood, Shakeel A. Simnani, Manzoor A. Malik

Turkish Journal of Physics

The description of gravitational galaxy clustering evolving through quasi-equilibrium thermodynamics is examined on the basis of thermodynamic fluctuations and statistical mechanical ensemble techniques. Second order fluctuation moments lead to an ordinary differential equation for b(nT^{-3}), ratio of gravitational correlation energy to (twice) the kinetic energy of peculiar velocities. The general solution of the differential equation gives a functional form of b in terms of a scale invariant function nT^{-3}, in conformity with the earlier results. A method for finding analytic expression for probability distribution function f(N) of gravitational clustering in a expanding universe is also developed on the basis of …

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