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The Collegian (2009-02-09), Linet Cisneros Feb 2009

The Collegian (2009-02-09), Linet Cisneros

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 61, No. 20


The Collegian (2009-01-26), Linet Cisneros Jan 2009

The Collegian (2009-01-26), Linet Cisneros

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 61, No. 18


Einstein@Home Search For Periodic Gravitational Waves In Ligo S4 Data, B. Abbott, R. Abbott, R. Adhikari, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Joseph D. Romano Jan 2009

Einstein@Home Search For Periodic Gravitational Waves In Ligo S4 Data, B. Abbott, R. Abbott, R. Adhikari, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Joseph D. Romano

Physics & Astronomy Faculty Publications

A search for periodic gravitational waves, from sources such as isolated rapidly spinning neutron stars, was carried out using 510 h of data from the fourth LIGO science run (S4). The search was for quasimonochromatic waves in the frequency range from 50 to 1500 Hz, with a linear frequency drift ˙�� (measured at the solar system barycenter) in the range −��/��<˙��<0.1⁢��/��, where the minimum spin-down age �� was 1000 yr for signals below 300 Hz and 10 000 yr above 300 Hz. The main computational work of the search was distributed over approximately 100 000 computers volunteered by the general public. This large computing power allowed the use of a relatively long coherent integration time of 30 h, despite the large parameter space searched. No statistically significant signals were found. The sensitivity of the search is estimated, along with the fraction of parameter space that was vetoed because of contamination by instrumental artifacts. In the 100 to 200 Hz band, more than 90% of sources with dimensionless gravitational-wave strain amplitude greater than 10−23 would have been detected.


Gec1-Kappa Opioid Receptor Binding Involves Hydrophobic Interactions Gec1 Has Chaperone-Like Effect, Yong Chen, Chongguang Chen, Evangelia Kotsikorou, Diane L. Lynch, Patricia H. Reggio, Lee Yuan Liu-Chen Jan 2009

Gec1-Kappa Opioid Receptor Binding Involves Hydrophobic Interactions Gec1 Has Chaperone-Like Effect, Yong Chen, Chongguang Chen, Evangelia Kotsikorou, Diane L. Lynch, Patricia H. Reggio, Lee Yuan Liu-Chen

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

We demonstrated previously that the protein GEC1 (glandular epithelial cell 1) bound to the human κ opioid receptor (hKOPR) and promoted cell surface expression of the receptor by facilitating its trafficking along the secretory pathway. Here we showed that three hKOPR residues (Phe345, Pro346, and Met350) and seven GEC1 residues (Tyr49, Val51, Leu55, Thr56, Val57, Phe60, and Ile64) are indispensable for the interaction. Modeling studies revealed that the interaction was mediated via direct contacts between the kinked hydrophobic fragment in …


Analysis Of Flux-Base Fins For Estimation Of Heat Transfer Coefficient, Kevin D. Cole, Constantine Tarawneh, Brent M. Wilson Jan 2009

Analysis Of Flux-Base Fins For Estimation Of Heat Transfer Coefficient, Kevin D. Cole, Constantine Tarawneh, Brent M. Wilson

Mechanical Engineering Faculty Publications

Exact solutions are given for the transient temperature in flux-base fins with the method of Green’s functions (GF) in the form of infinite series for three different tip conditions. The speed of convergence is improved by replacing the steady part by a closed-form steady solution. For the insulated-tip case, a quasi-steady solution is presented. Numerical values are presented and the conditions under which the quasi-steady solution is accurate are determined. An experimental example is given for estimation of the heat transfer coefficient (HTC) on a non-rotating roller bearing, in which the outer bearing race is treated as a transient fin.


The Collegian (2009-01-12), Linet Cisneros Jan 2009

The Collegian (2009-01-12), Linet Cisneros

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 61, No. 16


Utb/Tsc Undergraduate Catalog 2009-2010, University Of Texas At Brownsville, Texas Southmost College Jan 2009

Utb/Tsc Undergraduate Catalog 2009-2010, University Of Texas At Brownsville, Texas Southmost College

UTB/TSC Archives - Course Catalogs

No abstract provided.


Utb/Tsc Graduate Catalog 2009-2011, University Of Texas At Brownsville, Texas Southmost College Jan 2009

Utb/Tsc Graduate Catalog 2009-2011, University Of Texas At Brownsville, Texas Southmost College

UTB/TSC Archives - Course Catalogs

No abstract provided.


Utb/Tsc Legacy Degree Programs 2009 – 2010, University Of Texas At Brownsville, Texas Southmost College Jan 2009

Utb/Tsc Legacy Degree Programs 2009 – 2010, University Of Texas At Brownsville, Texas Southmost College

UTB/TSC Archives - Course Catalogs

No abstract provided.


Orange & White - Winter 2009, University Of Texas At Brownsville, Texas Southmost College Jan 2009

Orange & White - Winter 2009, University Of Texas At Brownsville, Texas Southmost College

UTB/TSC Archives - Orange & White Magazine

No abstract provided.


Utb/Tsc Commencement – Winter 2009, University Of Texas At Brownsville, Texas Southmost College Jan 2009

Utb/Tsc Commencement – Winter 2009, University Of Texas At Brownsville, Texas Southmost College

Brownsville Archives - Legacy Commencement Programs

No abstract provided.


Utpa Undergraduate Catalog 2009-2011, University Of Texas Pan American Jan 2009

Utpa Undergraduate Catalog 2009-2011, University Of Texas Pan American

UTPA Archives - Course Catalogs

No abstract provided.


Utpa Graduate Catalog 2009-2011, University Of Texas Pan American Jan 2009

Utpa Graduate Catalog 2009-2011, University Of Texas Pan American

UTPA Archives - Course Catalogs

No abstract provided.


Education And Crime, Gordon A. Crews Jan 2009

Education And Crime, Gordon A. Crews

Criminal Justice Faculty Publications

The purpose of this chapter is to provide an overview of the topic of education and crime. While at first glance this appears to be a simple task, there is an inherent complexity in examining such a broad subject. There are many different perspectives from which a discussion of education and crime could develop. Criminologists might assume this would be an overview of the impact that an individual’s education level may have upon their criminal or anti-social behavior. On the other hand, parents might assume this is a discussion of the impact of school violence and crime upon the safety …


The Informational Content Of Canonical Disjoint Np-Pairs, Christian Glaßer, Alan L. Selman, Liyu Zhang Jan 2009

The Informational Content Of Canonical Disjoint Np-Pairs, Christian Glaßer, Alan L. Selman, Liyu Zhang

Computer Science Faculty Publications

We investigate the connection between propositional proof systems and their canonical pairs. It is known that simulations between propositional proof systems translate to reductions between their canonical pairs. We focus on the opposite direction and study the following questions.

Q1: For which propositional proof systems f and g does the implication hold, and for which does it fail?

Q2: For which propositional proof systems of different strengths are the canonical pairs equivalent?

Q3: What do (non-)equivalent canonical pairs tell about the corresponding propositional proof systems?

Q4: Is every NP-pair (A, B), where A is NP-complete, strongly many-one equivalent to the …


Search For Gravitational-Wave Bursts In The First Year Of The Fifth Ligo Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Hansheng Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano Jan 2009

Search For Gravitational-Wave Bursts In The First Year Of The Fifth Ligo Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Hansheng Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results obtained from an all-sky search for gravitational-wave (GW) bursts in the 64–2000 Hz frequency range in data collected by the LIGO detectors during the first year (November 2005—November 2006) of their fifth science run. The total analyzed live time was 268.6 days. Multiple hierarchical data analysis methods were invoked in this search. The overall sensitivity expressed in terms of the root-sum-square (rss) strain amplitude hrss for gravitational-wave bursts with various morphologies was in the range of 6×10−22  Hz−1/2 to a few×10−21  Hz−1/2. No GW signals were observed and a frequentist upper limit of 3.75 events per …


Probabilistic Analysis Of A Motif Discovery Algorithm For Multiple Sequences, Bin Fu, Ming-Yang Kao, Lusheng Wang Jan 2009

Probabilistic Analysis Of A Motif Discovery Algorithm For Multiple Sequences, Bin Fu, Ming-Yang Kao, Lusheng Wang

Computer Science Faculty Publications

We study a natural probabilistic model for motif discovery that has been used to experimentally test the quality of motif discovery programs. In this model, there are k background sequences, and each character in a background sequence is a random character from an alphabet Σ. A motif G = g1g2 · · · gm is a string of m characters. Each background sequence is implanted into a probabilistically generated approximate copy of G. For an approximate copy b1b2 · · · bm of G, every character bi is probabilistically generated such that the probability for r $b_i\neq g_i$ is at …


Stacked Search For Gravitational Waves From The 2006 Sgr 1900+14 Storm, B. P. Abbott, R. Abbott, R. Adhikari, Teviet Creighton, Matthew Benacquista, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano Jan 2009

Stacked Search For Gravitational Waves From The 2006 Sgr 1900+14 Storm, B. P. Abbott, R. Abbott, R. Adhikari, Teviet Creighton, Matthew Benacquista, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results of a LIGO search for short-duration gravitational waves (GWs) associated with the 2006 March 29 SGR 1900+14 storm. A new search method is used, \"stacking\" the GW data around the times of individual soft-gamma bursts in the storm to enhance sensitivity for models in which multiple bursts are accompanied by GW emission. We assume that variation in the time difference between burst electromagnetic emission and potential burst GW emission is small relative to the GW signal duration, and we time-align GW excess power time-frequency tilings containing individual burst triggers to their corresponding electromagnetic emissions. We use …


Risk Of Dementia Associated With Elevated Plasma Homocysteine In A Latin American Population, Inara J. Chacon, Aldrín E. Molero, Gloria Pino-Ramírez, José A. Luchsinger, Joseph H. Lee, Gladys E. Maestre Jan 2009

Risk Of Dementia Associated With Elevated Plasma Homocysteine In A Latin American Population, Inara J. Chacon, Aldrín E. Molero, Gloria Pino-Ramírez, José A. Luchsinger, Joseph H. Lee, Gladys E. Maestre

School of Medicine Publications

The relationship between total homocysteine (tHcy) and dementia risk remains controversial, as the association varies among populations and dementia subtypes. We studied a Venezuelan population that has high prevalence of both elevated tHcy and dementia. We tested the hypotheses that (1) elevated tHcy is associated with increased dementia risk, (2) the risk is greater for vascular dementia (VaD) than for Alzheimer’s disease (AD), and (3) a history of stroke may partly explain this association. 2100 participants (≥55 years old) of the Maracaibo Aging Study underwent standardized neurological, neuropsychiatric, and cardiovascular assessments. Elevated tHcy was significantly associated with dementia, primarily VaD. …


Arecibo Pulsar Survey Using Alpha: Probing Radio Pulsar Intermittency And Transients, J. S. Deneva, J. M. Cordes, M. A. Mclaughlin, D. J. Nice, D. R. Lorimer, F. Crawford, N. D.R. Bhat, F. Camilo, Fredrick A. Jenet, J. Van Leeuwen Jan 2009

Arecibo Pulsar Survey Using Alpha: Probing Radio Pulsar Intermittency And Transients, J. S. Deneva, J. M. Cordes, M. A. Mclaughlin, D. J. Nice, D. R. Lorimer, F. Crawford, N. D.R. Bhat, F. Camilo, Fredrick A. Jenet, J. Van Leeuwen

Physics & Astronomy Faculty Publications

We present radio transient search algorithms, results, and statistics from the ongoing Arecibo Pulsar ALFA (PALFA) survey of the Galactic plane. We have discovered seven objects through a search for isolated dispersed pulses. All of these objects are Galactic and have measured periods between 0.4 and 4.7 s. One of the new discoveries has a duty cycle of 0.01%, smaller than that of any other radio pulsar. We discuss the impact of selection effects on the detectability and classification of intermittent sources, and compare the efficiencies of periodicity and single-pulse (SP) searches for various pulsar classes. For some cases we …


Stellar Population Models And Individual Element Abundances. Ii. Stellar Spectra And Integrated Light Models, Hyun Chul Lee, Guy Worthey, Aaron Dotter, Brian Chaboyer, Darko Jevremović, E. Baron, Michael M. Briley, Jason W. Ferguson, Paula Coelho, Scott C. Trager Jan 2009

Stellar Population Models And Individual Element Abundances. Ii. Stellar Spectra And Integrated Light Models, Hyun Chul Lee, Guy Worthey, Aaron Dotter, Brian Chaboyer, Darko Jevremović, E. Baron, Michael M. Briley, Jason W. Ferguson, Paula Coelho, Scott C. Trager

Physics & Astronomy Faculty Publications

The first paper in this series explored the effects of altering the chemical mixture of the stellar population on an element-by-element basis on stellar evolutionary tracks and isochrones to the end of the red giant branch. This paper extends the discussion by incorporating the fully consistent synthetic stellar spectra with those isochrone models in predicting integrated colors, Lick indices, and synthetic spectra. Older populations display element ratio effects in their spectra at higher amplitude than younger populations. In addition, spectral effects in the photospheres of stars tend to dominate over effects from isochrone temperatures and lifetimes, but, further, the isochrone-based …


Xafs Debye-Waller Factors For Deformed Hemes And Metal Substituted Hemes, Nicholas Dimakis, T. Mion, C. Ramirez, G. Bunker Jan 2009

Xafs Debye-Waller Factors For Deformed Hemes And Metal Substituted Hemes, Nicholas Dimakis, T. Mion, C. Ramirez, G. Bunker

Physics & Astronomy Faculty Publications

We present an efficient and accurate method for calculating XAFS Debye-Waller factors for deformed active sites of hemoproteins and metal substituted hemes. Based on the Normal Coordinate Structural Decomposition scheme, the deformation of the porphyrin macrocycle is expressed as a linear combination of the normal modes of the planar species. In our approach, we identify the modes that contribute most to the deformation. Small metal-porphyrin structures which match the macrocycle structural deformation of the deformed hemoprotein site are used to calculate the Debye-Waller parameters at sample's temperature. The Debye-Waller factors are directly obtained by calculating the normal mode spectrum of …


Strong Field Effects On Pulsar Arrival Times: Circular Orbits And Equatorial Beams, Yan Wang, Fredrick Jenet, Teviet Creighton, Richard H. Price Jan 2009

Strong Field Effects On Pulsar Arrival Times: Circular Orbits And Equatorial Beams, Yan Wang, Fredrick Jenet, Teviet Creighton, Richard H. Price

Physics & Astronomy Faculty Publications

If a pulsar orbits a supermassive black hole, the timing of pulses that pass close to the hole will show a variety of strong field effects. To compute the intensity and timing of pulses that have passed close to a nonrotating black hole, we introduce here a simple formalism based on two \"universal functions,\" one for the bending of photon trajectories and the other for the photon travel time on these trajectories. We apply this simple formalism to the case of a pulsar in circular orbit that beams its pulses into the orbital plane. In addition to the \"primary\" pulses …


Strong Field Effects On Pulsar Arrival Times: General Orientations, Yan Wang, Teviet Creighton, Richard H. Price, Fredrick A. Jenet Jan 2009

Strong Field Effects On Pulsar Arrival Times: General Orientations, Yan Wang, Teviet Creighton, Richard H. Price, Fredrick A. Jenet

Physics & Astronomy Faculty Publications

A pulsar beam passing close to a black hole can provide a probe of very strong gravitational fields even if the pulsar itself is not in a strong field region. In the case that the spin of the hole can be ignored, we have previously shown that all strong field effects on the beam can be understood in terms of two \"universal\" functions: F(φin) and T(φin) of the angle of beam emission φin; these functions are universal in that they depend only on a single parameter, the pulsar/black hole distance from which the beam is emitted. Here we apply this …


Search For Gravitational Waves From Low Mass Compact Binary Coalescence In 186 Days Of Ligo’S Fifth Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, K. Hayama, H. Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone, Lappoon R. Tang Jan 2009

Search For Gravitational Waves From Low Mass Compact Binary Coalescence In 186 Days Of Ligo’S Fifth Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, K. Hayama, H. Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone, Lappoon R. Tang

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from coalescing compact binaries, of total mass between 2 and 35M⊙, using LIGO observations between November 14, 2006 and May 18, 2007. No gravitational-wave signals were detected. We report upper limits on the rate of compact binary coalescence as a function of total mass. The LIGO cumulative 90%-confidence rate upper limits of the binary coalescence of neutron stars, black holes and black hole-neutron star systems are 1.4×10−2, 7.3×10−4 and 3.6×10−3  yr−1 L−110, respectively, where L10 is 1010 times the blue solar luminosity.


Highly Stereoselective B-Lactam Synthesis Via The Staudinger Reaction Using Poly Aromatic Imines, Debasish Bandyopadhyay, Monica Xavier, Bimal K. Banik Jan 2009

Highly Stereoselective B-Lactam Synthesis Via The Staudinger Reaction Using Poly Aromatic Imines, Debasish Bandyopadhyay, Monica Xavier, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Highly stereoselective synthesis of a few trans 3-phthalimido substituted B-lactams has been achieved following Staudinger reaction.


Structure Of Polc Reveals Unique Dna Binding And Fidelity Determinants, Ronald J. Evans, Douglas R. Davies, James M. Bullard, Jeffrey Christensen, Louis S. Green, Joseph W. Guiles, Janice D. Pata, Wendy K. Ribble, Nebojsa Janjic, Thale C. Jarvis Dec 2008

Structure Of Polc Reveals Unique Dna Binding And Fidelity Determinants, Ronald J. Evans, Douglas R. Davies, James M. Bullard, Jeffrey Christensen, Louis S. Green, Joseph W. Guiles, Janice D. Pata, Wendy K. Ribble, Nebojsa Janjic, Thale C. Jarvis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

PolC is the polymerase responsible for genome duplication in many Gram-positive bacteria and represents an attractive target for antibacterial development. We have determined the 2.4-Å resolution crystal structure of Geobacillus kaustophilus PolC in a ternary complex with DNA and dGTP. The structure reveals nascent base pair interactions that lead to highly accurate nucleotide incorporation. A unique β-strand motif in the PolC thumb domain contacts the minor groove, allowing replication errors to be sensed up to 8 nt upstream of the active site. PolC exhibits the potential for large-scale conformational flexibility, which could encompass the catalytic residues. The structure suggests a …


Locality And Stability Of The Cascades Of Two-Dimensional Turbulence, Eleftherios Gkioulekas Dec 2008

Locality And Stability Of The Cascades Of Two-Dimensional Turbulence, Eleftherios Gkioulekas

School of Mathematical & Statistical Sciences Faculty Publications

We investigate and clarify the notion of locality as it pertains to the cascades of two-dimensional turbulence. The mathematical framework underlying our analysis is the infinite system of balance equations that govern the generalized unfused structure functions, first introduced by L’vov and Procaccia. As a point of departure we use a revised version of the system of hypotheses that was proposed by Frisch for three-dimensional turbulence. We show that both the enstrophy cascade and the inverse energy cascade are local in the sense of nonperturbative statistical locality. We also investigate the stability conditions for both cascades. We have shown that …


The Collegian (2008-12-01), Isis Lopez Dec 2008

The Collegian (2008-12-01), Isis Lopez

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 61, No. 15


Experiments And Models For The Thermal Response Of Railroad Tapered-Roller Bearings, Constantine Tarawneh, Kevin D. Cole, Brent Wilson, Fadi Alnaimat Dec 2008

Experiments And Models For The Thermal Response Of Railroad Tapered-Roller Bearings, Constantine Tarawneh, Kevin D. Cole, Brent Wilson, Fadi Alnaimat

Mechanical Engineering Faculty Publications

The need to understand and quantify the heat transfer paths within tapered-roller bearings is of great importance in the railroad industry since bearing cup temperature measurement is the primary tool utilized in the removal of distressed bearings from service. Experiments were performed to acquire temperature histories at several locations on a stationary bearing subjected to heat sources imbedded in two rollers. The experimental results were compared to zero- and first-order thermal models to estimate overall heat transfer coefficients from the bearing. The results presented here can be used to explain some of the mechanisms that lead to overheating of tapered-roller …