Physical Sciences and Mathematics Commons^™

G Factor Of The 2+1 State Of 170Hf, A. Wolf, Z. Berant, A. Heinz, V. Werner, E. A. Mccutchan, G. Gurdal, R. Cakirli, Y. Oktem, J. Ai, L. Amon, C. W. Beausang, D. S. Brenner, R. F. Casten, R. J. Casperson, K. Dusling, C. R. Fitzpatrick, A. B. Gransworthy, N. Pietralla, J. Qian, P. H. Regan, N. J. Thompson, E. Williams, R. Winkler

Physics Faculty Publications

The g factor of the 2⁺₁ state of ¹⁷⁰Hf was measured by perturbed γ-γ angular correlation in a static external magnetic field. The result, g(2⁺₁) = 0.28(5), extends the systematics of g factors of even-even Hf isotopes to N = 98 and enables a better test of theoretical models. The g(2⁺₁) experimental values of these isotopes exhibit a remarkable constancy as a function of neutron number. This phenomenon, which was also observed for other isotopic chains in the Gd–W range, is explained in terms of a recently proposed empirical …

High-Spin States In 191, 193Au And 192Pt: Evidence For Oblate Deformation And Triaxial Shapes, Y. Oktem, D. L. Balabanski, B. Akkus, C. W. Beausang, M. Bostan, R. Cakirli, R. F. Casten, M. Danchev, M. Djongolov, M. N. Erduran, S. Erturk, K. A. Gladniski, G. Gurdal, J. Tm. Goon, D. J. Hartley, A. A. Hecht, R. Krucken, N. Nikolov, J. R. Novak, G. Rainovski, L. L. Riedinger, I. Yigitoglu, N. V. Zamfir, O. Zeidan

Physics Faculty Publications

High-spin states of ^{191, 193}Au and ¹⁹²Pt have been populated in the ¹⁸⁶W(¹¹B, xn) and ¹⁸⁶W(¹¹B, p4n) reactions, respectively, at a beam energy of 68 MeV and their γ decay was studied using the YRAST Ball detector array at the Wright Nuclear Structure Laboratory at Yale University. The level scheme of ¹⁹³Au has been extended up to I^π = 55/2⁺. New transitions were observed also in ¹⁹¹Au and ¹⁹²Pt. Particle-plus-Triaxial-Rotor (PTR) and Total Routhian Surface (TRS) calculations were performed to determine the equilibrium deformations of the …

Constraining F(R) Gravity As A Scalar-Tensor Theory, Thomas Faulkner, Max Tegmark, Emory F. Bunn, Yi Mao

Physics Faculty Publications

We search for viable f(R) theories of gravity, making use of the equivalence between such theories and scalar-tensor gravity. We find that models can be made consistent with solar system constraints either by giving the scalar a high mass or by exploiting the so-called chameleon effect. However, in both cases, it appears likely that any late-time cosmic acceleration will be observationally indistinguishable from acceleration caused by a cosmological constant. We also explore further observational constraints from, e.g., big bang nucleosynthesis and inflation.

Absolute And Relative Surrogate Measurements Of The 236U(N,F) Cross Section As A Probe Of Angular Momentum Effects, B. F. Lyles, L. A. Bernstein, J. T. Burke, F. S. Dietrich, J. Escher, I. Thompson, D. L. Bleuel, R. M. Clark, P. Fallon, J. Gibelin, A. O. Macchiavelli, M. A. Mcmahan, L. Phair, E. Rodriguez-Vieitez, M. Wiedeking, C. W. Beausang, S. R. Lesher, B. Darakchieva, M. Evtimova

Physics Faculty Publications

Using both the absolute and relative surrogate techniques, the ²³⁶U(n,f) cross section was deduced over an equivalent neutron energy range of 0 to 20 MeV. A 42 MeV ³He beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to perform a (³He,α) pickup reaction on targets of ²³⁵U (J^π=7/2⁻) and ²³⁸U (J^π = 0⁺) and the fission decay probabilities were determined. The ²³⁵U(³He,αf) and ²³⁸U(³He,αf) were surrogates for ^{233 …}

Directionality In The Wilkinson Microwave Anisotropy Probe Polarization Data, D. Hanson, Douglas Scott, Emory F. Bunn

Physics Faculty Publications

Polarization is the next frontier of cosmic microwave background analysis, but its signal is dominated over much of the sky by foregrounds which must be carefully removed. To determine the efficacy of this cleaning, it is necessary to have sensitive tests for residual foreground contamination in polarization sky maps. The dominant Galactic foregrounds introduce a large-scale anisotropy on to the sky, so it makes sense to use a statistic sensitive to overall directionality for this purpose. Here, we adapt the rapidly computable D statistic of Bunn and Scott to polarization data, and demonstrate its utility as a foreground monitor by …

Proof Of The Barker Array Conjecture, James A. Davis, Jonathan Jedwab, Ken W. Smith

Department of Math & Statistics Faculty Publications

Using only elementary methods, we prove Alquaddoomi and Scholtz’s conjecture of 1989, that no s × t Barker array having s, t > 1 exists except when s = t = 2.

Stable Aqueous Nanoparticle Film Assemblies With Covalent And Charged Polymer Linking Networks, Lesley E. Russell, Anne A. Galyean, Sherilyn M. Notte, Michael C. Leopold

Chemistry Faculty Publications

The construction of highly stable and efficiently assembled multilayer films of purely water soluble gold nanoparticles is reported. Citrate-stabilized nanoparticles (CS-NPs) of average core diameter of 10 nm are used as templates for stabilization-based exchange reactions with thioctic acid to form more robust aqueous NPs that can be assembled into multilayer films. The thioctic acid stabilized nanoparticles (TAS-NPs) are networked via covalent and electrostatic linking systems, employing dithiols and the cationic polymer poly(l-lysine), respectively. Multilayer films of up to 150 nm in thickness are successfully grown at biological pH with no observable degradation of the NPs within the film. The …

A Series Of Vertically Integrated Nanotechnology Experiments For The Undergraduate Curriculum, Kevin W. Kittredge, Lesley E. Russell, Michael C. Leopold

Chemistry Faculty Publications

We have designed three nanotechnology experiments that are vertically integrated for an undergraduate chemistry curriculum. They are an evolving set of experiments for sequential courses in an undergraduate chemistry program. These experiments are designed to match the student's level of understanding for each particular course. The participating student is involved in a "research" project that progresses in both theory and experimental technique. Students benefit from these vertically integrated experiments by being involved in multiple facets of a simulated research project. This mimics a traditional research project under an advisor's supervision without the undesired drawback of an unknown outcome.

A Tandem Enol Silane Formation-Mukaiyama Aldol Reaction Mediated By Tmsotf, C. Wade Downey, Miles W. Johnson

Chemistry Faculty Publications

A slight excess of silyl trifluoromethanesulfonate mediates a tandem enol silane formation-Mukaiyama aldol reaction in the presence of Hunig’s base. Preformation of the enol silane is unnecessary for efficient reactions, which proceed in 75–97% yield for the addition of aryl methyl ketones and acetate esters to non-enolizable aldehydes. Mechanistic data suggests that free amine is crucial for full conversion.

Systematic Errors In Cosmic Microwave Background Interferometry, Emory F. Bunn

Physics Faculty Publications

Cosmic microwave background (CMB) polarization observations will require superb control of systematic errors in order to achieve their full scientific potential, particularly in the case of attempts to detect the B modes that may provide a window on inflation. Interferometry may be a promising way to achieve these goals. This paper presents a formalism for characterizing the effects of a variety of systematic errors on interferometric CMB polarization observations, with particular emphasis on estimates of the B-mode power spectrum. The most severe errors are those that couple the temperature anisotropy signal to polarization; such errors include cross talk within …

Detection And Estimation Of A Mixture In Power Law Processes For A Repairable System, Ni Wang, Paul Kvam, Jye-Chyi Lu

Department of Math & Statistics Faculty Publications

The power law process has proved to be a useful tool in characterizing the failure process of repairable systems. This paper presents a procedure for detecting and estimating a mixture of reliable and unreliable (defective) systems. The test of a mixture, based on a simple likelihood ratio, is illustrated with truncated failure data for copy machines. Bootstrap methods are used to gauge the estimation uncertainty, and optimal decisions for system replacement are determined based on the observed likelihood.

Crossover Property Of The Nonperiodic Autocorrelation Of Quaternary Sequences, Michael Pohl

Honors Theses

Sequences with identical nonperiodic autocorrelation functions have recently been used to construct Golay sequences different than the Davis-Jedwab construction. In this thesis, we construct infinite families of quaternary sequences with identical non periodic autocorrelation functions. These results demonstrate that current con­ structions for quaternary families are not all encompassing and need further study.

Spin Dependence Of K Mixing, Strong Configuration Mixing, And Electromagnetic Properties Of 178Hf, A. B. Hayes, D. Cline, C. Y. Wu, H. Ai, H. Amro, C. W. Beausang, R. F. Casten, J. Gerl, A. A. Hecht, A. Heinz, H. Hua, R. O. Hughes, R.V. F. Janssens, C. J. Lister, A. O. Macchiavelli, D. A. Meyer, E. F. Moore, P. Napiorkowski, R. C. Pardo, Ch. Schlegel, D. Seweryniak, M. W. Simon, J. Srebrny, R. Teng, K. Vetter, H. J. Wollersheim

Physics Faculty Publications

The combined data of two Coulomb excitation experiments has verified the purely electromagnetic population of the K^π = 4⁺, 6⁺, 8⁻, and 16⁺rotational bands in ¹⁷⁸Hf via 2≤ν ≤14 K-forbidden transitions, quantifying the breakdown of the K-selection rule with increasing spin in the low-K bands. The γ -, 4⁺, and 6⁺bands were extended, and four new states in a rotational band were tentatively assigned to a previously known K^π = 0⁺band. The quasiparticle structure of the 6⁺( …

Mosaicking With Cosmic Microwave Background Interferometers, Emory F. Bunn, Martin White

Physics Faculty Publications

Measurements of cosmic microwave background (CMB) anisotropies by interferometers offer several advantages over single-dish observations. The formalism for analyzing interferometer CMB data is well developed in the flat-sky approximation, which is valid for small fields of view. As the area of sky is increased to obtain finer spectral resolution, this approximation needs to be relaxed. We extend the formalism for CMB interferometry, including both temperature and polarization, to mosaics of observations covering arbitrarily large areas of the sky, with each individual pointing lying within the flat-sky approximation. We present a method for computing the correlation between visibilities with arbitrary pointing …

Isospin Purity Of T=1 States In The A=38 Nuclei Studied Via Lifetime Measurements In K38, F. M. Prados Estevez, A. M. Bruce, M. J. Taylor, H. Amro, C. W. Beausang, R. F. Casten, J. J. Ressler, C. J. Barton, C. Chandler, G. Hammond

Physics Faculty Publications

The Doppler Shift Attenuation Method was used to measure lifetimes for levels in 38K at excitation energies of 1698, 2404, 2830, 2996, and 3671 keV, populated using the 40Ca(d, α) 38K reaction at a beam energy of 4.5 MeV. Values of 109(29), 95(22), 457(63), 130(40), and 160(50) fs, respectively, were measured and are compared with previous values obtained using different stopping powers. The matrix element for the transition between the Jπ = 2+ T=1 and 0+ T=1 states in this Tz = 0 nucleus is compared with the analogous transition in the other nuclei in the T = 1 triplet, …

Centers And Shore Points In Λ-Dendroids, Van C. Nall

Department of Math & Statistics Faculty Publications

A dendroid is the disjoint union of the set of centers and the set of shore points. We show this is also true for λ-dendroids and use this fact to show that the finite union of shore continua in a λ-dendroid is a shore set.

An Observation About Frostman Shifts, William T. Ross, Alec L. Matheson

Department of Math & Statistics Faculty Publications

A classical theorem of Frostman says that if B is a Blaschke product (or any inner function), then its Frostman shifts B_w = (B − w)(1 – w­­¯B)⁻¹ are Blaschke products for all |w| < 1 except possibly for w in a set of logarithmic capacity zero. If B is a Frostman Blaschke product, equivalently an inner multiplier for the space of Cauchy transforms of measures on the unit circle, we show that for all |w| < 1, B_w is indeed another Frostman Blaschke product.

Design And Implementation Of Interactive Tutorials For Data Structures, Lewis Barnett Iii

Department of Math & Statistics Faculty Publications

The Tutorial Generation Toolkit (TGT) is a set of Java classes that supports authoring interactive tutorial applications. This paper describes extensions to the capabilities of the TGT to support styles of interaction identified as effective in recent research. Several new tutorials aimed at the data structures course built using the enhanced toolkit are also described.

Degradation Models And Implied Lifetime Distributions, Suk Joo Bae, Way Kuo, Paul H. Kvam

Department of Math & Statistics Faculty Publications

In experiments where failure times are sparse, degradation analysis is useful for the analysis of failure time distributions in reliability studies. This research investigates the link between a practitioner's selected degradation model and the resulting lifetime model. Simple additive and multiplicative models with single random effects are featured. Results show that seemingly innocuous assumptions of the degradation path create surprising restrictions on the lifetime distribution. These constraints are described in terms of failure rate and distribution classes.

Statistical Models For Hot Electron Degradation In Nano-Scaled Mosfet Devices, Suk Joo Bae, Seong-Joon Kim, Way Kuo, Paul H. Kvam

Department of Math & Statistics Faculty Publications

In a MOS structure, the generation of hot carrier interface states is a critical feature of the item's reliability. On the nano-scale, there are problems with degradation in transconductance, shift in threshold voltage, and decrease in drain current capability. Quantum mechanics has been used to relate this decrease to degradation, and device failure. Although the lifetime, and degradation of a device are typically used to characterize its reliability, in this paper we model the distribution of hot-electron activation energies, which has appeal because it exhibits a two-point discrete mixture of logistic distributions. The logistic mixture presents computational problems that are …

[Introduction To] Nonparametric Statistics With Applications To Science And Engineering, Paul Kvam, Brani Vidakovic

Bookshelf

This book presents a practical approach to nonparametric statistical analysis and provides comprehensive coverage of both established and newly developed methods. With the use of MATLAB, the authors present information on theorems and rank tests in an applied fashion, with an emphasis on modern methods in regression and curve fitting, bootstrap confidence intervals, splines, wavelets, empirical likelihood, and goodness-of-fit testing.

Nonparametric Statistics with Applications to Science and Engineering begins with succinct coverage of basic results for order statistics, methods of categorical data analysis, nonparametric regression, and curve fitting methods. The authors then focus on nonparametric procedures that are becoming more …

[Introduction To] Schaum's Outline Of Data Structures With Java, John R. Hubbard

Bookshelf

Schaum's Outlines are the key to faster learning and higher grades in every subject. Each Outline presents all the essential course information in an easy-to-follow, topic-by-topic format. You also get hundreds of examples, solved problems, and practice exercises to test your skills.

Schaum's Outline of Data Structures with Java gives you:

• Practice problems with full explanations that reinforce knowledge
• Coverage of the most up-to-date developments in your course field
• In-depth review of practices and applications

Fully compatible with your classroom text, Schaum's highlights all the important facts you need to know.

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 …

Indigenous Land Tenure Insecurity Fosters Illegal Logging In Nicaragua, Mary Finley-Brook

Geography and the Environment Faculty Publications

Titling of Indigenous common-property lands in easternNicaraguais a necessary base for forest management. Titling alone will not be sufficient to assure sustainable practices, and the success of demarcation programmes rests on processes of negotiation leading up to tenure decisions; nevertheless, a review of decades of history in Indigenous territories suggests that key problems in forest resource administration are inextricably linked to tenure insecurities, as explorations of current resource disputes in seven villages demonstrate. Analysis also suggests that ineffective implementation ofNicaragua’s multiethnic autonomy fosters illegality and resource mismanagement. Fundamental structural changes to improve inclusion, accountability and transparency are necessary. Remediation also …

An Eye-Opening Approach To Developing And Communicating Integrated Environmental Assessments, Todd R. Lookingbill, William C. Dennison, Tim J.B. Carruthers, Jane M. Hawkey, Shawn L. Carter

Geography and the Environment Faculty Publications

Communication among managers, the public, and scientists is the key to successful ecosystem management; however, the varied perspectives and interests of these groups can make such communication difficult. One way to achieve effective communication is to develop a common knowledge base by combining syntheses of key scientific results with information-rich visual elements. Within a management landscape, integrated environmental assessments provide a useful framework for evaluating resources and directing management efforts. The integrated assessment process involves (1) initial investigation, (2) development of a conceptual framework, (3) data navigation, (4) environmental report cards, and (5) science communication. Each step requires the synthesis …