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2007

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Articles 1411 - 1440 of 6758

Full-Text Articles in Physical Sciences and Mathematics

Inference For Survival Curves With Informatively Coarsened Discrete Event-Time Data: Application To Alive, Michelle Shardell, Daniel O. Scharfstein, David Vlahov, Noya Galai Aug 2007

Inference For Survival Curves With Informatively Coarsened Discrete Event-Time Data: Application To Alive, Michelle Shardell, Daniel O. Scharfstein, David Vlahov, Noya Galai

Johns Hopkins University, Dept. of Biostatistics Working Papers

In many prospective studies, including AIDS Link to the Intravenous Experience (ALIVE), researchers are interested in comparing event-time distributions (e.g.,for human immunodeficiency virus seroconversion) between a small number of groups (e.g., risk behavior categories). However, these comparisons are complicated by participants missing visits or attending visits off schedule and seroconverting during this absence. Such data are interval-censored, or more generally,coarsened. Most analysis procedures rely on the assumption of non-informative censoring, a special case of coarsening at random that may produce biased results if not valid. Our goal is to perform inference for estimated survival functions across a small number of …


Characteristics Of Short-Period Wavelike Features Near 87 Km Altitude From Airglow And Lidar Observations Over Maui, J. H. Hecht, A. Z. Liu, R. L. Walterscheid, S. J. Franke, R. J. Rudy, M. J. Taylor, P. -D. Pautet Aug 2007

Characteristics Of Short-Period Wavelike Features Near 87 Km Altitude From Airglow And Lidar Observations Over Maui, J. H. Hecht, A. Z. Liu, R. L. Walterscheid, S. J. Franke, R. J. Rudy, M. J. Taylor, P. -D. Pautet

Physical Sciences - Daytona Beach

Small-scale (less than 15 km horizontal wavelength) wavelike structures known as ripples are a common occurrence in OH airglow images. Recent case studies attribute their origin to the presence of either convective or dynamical instabilities. However, little is known about their frequency of occurrence and period. The Maui-MALT Observatory, located at Mt. Haleakala, is instrumented with a Na wind/temperature lidar, which allows the determination of whether the atmosphere is dynamically or convectively unstable, and a fast OH airglow camera which takes images every 3 s with a sensitivity high enough to see the ripples. This study reports on 2 months …


Bose-Einstein Correlations Of Charged And Neutral Kaons In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi Aug 2007

Bose-Einstein Correlations Of Charged And Neutral Kaons In Deep Inelastic Scattering At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, M. Jechow, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, G. Sartorelli, A. Zichichi

Faculty Publications

Bose-Einstein correlations of charged and neutral kaons have been measured in e ± p deep inelastic scattering with an integrated luminosity of 121 pb -1 using the ZEUS detector at HERA. The two-particle correlation function was studied as a function of the four-momentum difference of the kaon pairs, Q 12 = sqrt(- (p 1 - p 2) 2), assuming a Gaussian shape for the particle source. The values of the radius of the production volume, r, and of the correlation strength, λ, were obtained for both neutral and charged kaons. The radii for charged and neutral kaons are similar and …


An Implementation Of A Cross-Platform Wireless Router Operating System, David Hunt Aug 2007

An Implementation Of A Cross-Platform Wireless Router Operating System, David Hunt

Regis University Student Publications (comprehensive collection)

The aim of this project was to develop an open-source wireless router platform on several Single Board Computers (SBCs) of different architectures. It is a Linux distribution that is common to all supported boards, with Ethernet drivers, Wireless drivers, web-interface, persistent storage of settings, and remote upgrade capability.


The Renewable Engergy Boom: How Nevada Is Playing A Vital Role In The Growth Market, Kathleen M. Drakulich Aug 2007

The Renewable Engergy Boom: How Nevada Is Playing A Vital Role In The Growth Market, Kathleen M. Drakulich

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Energy Conservation Opportunities In The Hotel And Casino Sector, Eric Dominguez Aug 2007

Energy Conservation Opportunities In The Hotel And Casino Sector, Eric Dominguez

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Dri’S Green Power Program And Renewable Energy Center, Kent Hoekman Aug 2007

Dri’S Green Power Program And Renewable Energy Center, Kent Hoekman

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Solar Generations, Larry Burton Aug 2007

Solar Generations, Larry Burton

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Nellis Afb Photovoltaic Array, Michelle Price Aug 2007

Nellis Afb Photovoltaic Array, Michelle Price

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Projects Of The Center For Energy Research, Robert F. Boehm Aug 2007

Projects Of The Center For Energy Research, Robert F. Boehm

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas. Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Renewable Energy - The Future Is Now, Thomas Fair Aug 2007

Renewable Energy - The Future Is Now, Thomas Fair

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


2007 Symposium Schedule, University Of Nevada Las Vegas Aug 2007

2007 Symposium Schedule, University Of Nevada Las Vegas

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas.

Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Photos From The 2007 Symposium, University Of Nevada Las Vegas Aug 2007

Photos From The 2007 Symposium, University Of Nevada Las Vegas

UNLV Renewable Energy Symposium

This inaugural event is dedicated to showcasing the renewable/sustainable energy projects of UNLV faculty, staff, students, and collaborators, as well as other external projects underway statewide and nationally. The development and utilization of new technologies to protect the environment, achieve energy independence, and strengthen the economy will be explored. Speakers and poster-session presenters will provide further insight to many ongoing projects and innovative research ideas. Organized by UNLV’s Office of Strategic Energy Programs, the event offers participants the opportunity to learn about energy projects and will encourage networking and collaboration. This symposium is intended for researchers, educators, students, policy makers, …


Efficient Angular Dispersion Compensation In Holographic Generation Of Intense Ultrashort Paraxial Beam Modes, James Strohaber, C. Petersen, Cornelis J. Uiterwaal Aug 2007

Efficient Angular Dispersion Compensation In Holographic Generation Of Intense Ultrashort Paraxial Beam Modes, James Strohaber, C. Petersen, Cornelis J. Uiterwaal

C.J.G.J. Uiterwaal Publications

We experimentally demonstrate that small misalignments of the pulse stretcher or compressor of our chirped-pulse-amplification laser can precompensate for angular chirp when producing ultrashort paraxial beam modes with holographic gratings. Using this approach we can eliminate one of the two gratings needed in our 2f–2f setup [Mariyenko et al., Opt. Express 13, 7599 (2005)]. This allows for up to an order of magnitude more output power. We see our method as the next step in the production of intense exotic forms of ultrashort pulses, which can be used in the investigation of intense laser–matter interactions. In addition, …


The Discrete Logarithm Problem And Ternary Functional Graphs, Max F. Brugger, Christina A. Frederick Aug 2007

The Discrete Logarithm Problem And Ternary Functional Graphs, Max F. Brugger, Christina A. Frederick

Mathematical Sciences Technical Reports (MSTR)

Encryption is essential to the security of transactions and communications, but the algorithms on which they rely might not be as secure as we all assume. In this paper, we investigate the randomness of the discrete exponentiation function used frequently in encryption. We show how we used exponential generating functions to gain theoretical data for mapping statistics in ternary functional graphs. Then, we compare mapping statistics of discrete exponentiation functional graphs, for a range of primes, with mapping statistics of the respective ternary functional graphs.


Poly[Μ2-Nitrato-(Μ4-Pyrazine-2-Carboxylato)Disilver(I)], Kathryn L. Seward, Joseph M. Ellsworth, Zeeshan M. Khaliq, Hans-Conrad Zur Loye Aug 2007

Poly[Μ2-Nitrato-(Μ4-Pyrazine-2-Carboxylato)Disilver(I)], Kathryn L. Seward, Joseph M. Ellsworth, Zeeshan M. Khaliq, Hans-Conrad Zur Loye

Faculty Publications

The title compound, [Ag2(C5H3N2O2)(NO3)]n, is a three-dimensional coordination polymer containing two-dimensional slabs held together by bridging nitrate groups. AgNO4 and AgNO5 silver coordination polyhedra arise. Weak argentophilic interactions [AgAg = 3.0686 (7) Å] occur in the crystal structure.


P–C And C–H Bond Cleavages Of Dppm In The Thermal Reaction Of [Ru3(Co)10(Μ-Dppm)] With Benzothiophene: X-Ray Structures Of [Ru6(Μ-Co)(Co)134-Php(C6H4)Pph}(Μ6-C)] And [Ru4(Co)932-Phpch2Pph2)(Μ4611-C6H4)(Μ-H)], Shariff E. Kabir, Mohammad R. Hassan, Daniel T. Haworth, Sergey V. Lindeman, Tasneem Siddiquee, Dennis W. Bennett Aug 2007

P–C And C–H Bond Cleavages Of Dppm In The Thermal Reaction Of [Ru3(Co)10(Μ-Dppm)] With Benzothiophene: X-Ray Structures Of [Ru6(Μ-Co)(Co)13{Μ4-Php(C6H4)Pph}(Μ6-C)] And [Ru4(Co)9(Μ3-Η2-Phpch2Pph2)(Μ4-Η6:Η1:Η1-C6H4)(Μ-H)], Shariff E. Kabir, Mohammad R. Hassan, Daniel T. Haworth, Sergey V. Lindeman, Tasneem Siddiquee, Dennis W. Bennett

Chemistry Faculty Research and Publications

The thermal reaction of [Ru3(CO)10(μ-dppm)] (1) with benzothiophene in refluxing toluene gives a complex mixture of products. These include the known compounds [Ru2(CO)6{μ-CH2PPh(C6H4)PPh}] (2), [Ru2(CO)6{μ-C6H4PPh(CH2)PPh}] (3), [Ru3(CO)933-(Ph)PCH2P(Ph)C6H4}] (4) and [Ru3(CO)10{μ-η2-PPh(CH2)(C6H4)PPh}] (6), as well as the new clusters [Ru6(μ-CO)(CO) …


Force-Response Considerations In Ciliary Mechanosensation, Andrew Resnick, Ulrich Hopfer Aug 2007

Force-Response Considerations In Ciliary Mechanosensation, Andrew Resnick, Ulrich Hopfer

Physics Faculty Publications

Considerable experimental evidence indicates that the primary, nonmotile cilium is a mechanosensory organelle in several epithelial cell types. As the relationship between cellular responses and nature and magnitude of applied forces is not well understood, we have investigated the effects of exposure of monolayers of renal collecting duct chief cells to orbital shaking and quantified the forces incident on cilia. An exposure of 24 h of these cells to orbital shaking resulted in a decrease of amiloride-sensitive sodium current by ∼60% and ciliary length by ∼30%. The sensitivity of the sodium current to shaking was dependent on intact cilia. The …


Phase Transition In U(1) Configuration Space: Oscillons As Remnants Of Vortex-Antivortex Annihilation, M. Gleiser, J. Thorarinson Aug 2007

Phase Transition In U(1) Configuration Space: Oscillons As Remnants Of Vortex-Antivortex Annihilation, M. Gleiser, J. Thorarinson

Dartmouth Scholarship

We show that the annihilation of vortex-antivortex pairs can lead to very long-lived oscillon states in 2d Abelian Higgs models. The emergence of oscillons is controlled by the ratio of scalar and vector field masses, β=(ms/mv)2 and can be described as a phase transition in field configuration space with critical value βc≃0.13(6)±2: only models with βO(β)∼|β−βc|o, where O is an order parameter indicating the presence of oscillons and o=0.2(2)±2 is the critical exponent.


Sensor Data Management, Cory Andrew Henson Aug 2007

Sensor Data Management, Cory Andrew Henson

Kno.e.sis Publications

No abstract provided.


Confidence Intervals For Population Size In A Capture-Recapture Problem., Xiao Zhang Aug 2007

Confidence Intervals For Population Size In A Capture-Recapture Problem., Xiao Zhang

Electronic Theses and Dissertations

In a single capture-recapture problem, two new Wilson methods for interval estimation of population size are derived. Classical Chapman interval, Wilson and Wilson-cc intervals are examined and compared in terms of their expected interval width and exact coverage properties in two models. The new approach performs better than the Chapman in each model. Bayesian analysis also gives a different way to estimate population size.


A Statistical Evaluation Of Algorithms For Independently Seeding Pseudo-Random Number Generators Of Type Multiplicative Congruential (Lehmer-Class)., Robert Grisham Stewart Aug 2007

A Statistical Evaluation Of Algorithms For Independently Seeding Pseudo-Random Number Generators Of Type Multiplicative Congruential (Lehmer-Class)., Robert Grisham Stewart

Electronic Theses and Dissertations

To be effective, a linear congruential random number generator (LCG) should produce values that are (a) uniformly distributed on the unit interval (0,1) excluding endpoints and (b) substantially free of serial correlation. It has been found that many statistical methods produce inflated Type I error rates for correlated observations. Theoretically, independently seeding an LCG under the following conditions attenuates serial correlation: (a) simple random sampling of seeds, (b) non-replicate streams, (c) non-overlapping streams, and (d) non-adjoining streams. Accordingly, 4 algorithms (each satisfying at least 1 condition) were developed: (a) zero-leap, (b) fixed-leap, (c) scaled random-leap, and (d) unscaled random-leap. Note …


Tricyclic Steiner Triple Systems With 1-Rotational Subsystems., Quan Duc Tran Aug 2007

Tricyclic Steiner Triple Systems With 1-Rotational Subsystems., Quan Duc Tran

Electronic Theses and Dissertations

A Steiner triple system of order v, denoted STS(v), is said to be tricyclic if it admits an automorphism whose disjoint cyclic decomposition consists of three cycles. In this thesis we give necessary and sufficient conditions for the existence of a tricyclic STS(v) when one of the cycles is of length one. In this case, the STS(v) will contain a subsystem which admits an automorphism consisting of a fixed point and a single cycle. The subsystem is said to be 1-rotational.


A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande Aug 2007

A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande

Electronic Theses and Dissertations

Many defects in physiological processes are due to free radical damage: reactive oxygen species, nitric oxide, and hydroxyl radicals have been implicated in the parthenogenesis of cancer, diabetes mellitus, and rheumatoid arthritis. We herein characterize the phenyl-N-ter-butyl nitrone (PBN) type spin traps in conjunction with the most studied dimethyl-1-pyrroline-N-oxide (DMPO) type spin traps using the hydroxyl radical. In this study, theoretical calculations are carried out on the two main types of spin traps (DMPO and PBN) at the density functional theory level (DFT). The energies of the optimized structures, hyperfine calculations in gaseous and aqueous phases of the spin traps …


Risk Assessment For Hazardous Materials Incident, Washington County, Tennessee: Road Transportation, Rail Transportation, And Hazardous Materials Storage., Steed Kenlee Stagnolia Aug 2007

Risk Assessment For Hazardous Materials Incident, Washington County, Tennessee: Road Transportation, Rail Transportation, And Hazardous Materials Storage., Steed Kenlee Stagnolia

Electronic Theses and Dissertations

This study was conducted to provide a quantitative risk assessment for road transportation, railway transportation, and storage of hazardous materials in Washington County, Tennessee. A roadside survey, railroad hazardous materials survey, and a chemical inventory were conducted. It revealed an estimated 267,858 HAZMAT shipments per year on primary and secondary roadways and an estimated total of 9.4 x 109 tons of HAZMAT shipped by rail per year. There are 49 facilities that store a daily average of 33,722,700 lbs of HAZMAT. The risk of a hazardous materials incident occurring in Washington County is highest for Interstate transportation. The risk for …


Beverage Consumption And Hypertension: Findings From The Third National Health And Nutrition Examination Survey., Vishal Arunbhai Mandge Aug 2007

Beverage Consumption And Hypertension: Findings From The Third National Health And Nutrition Examination Survey., Vishal Arunbhai Mandge

Electronic Theses and Dissertations

The study sample was comprised of 18,953 subjects aged 18 years and older who participated in the Third National Health and Nutrition Examination Survey. Preference for diet soda over regular soda was higher in females as compared to males and in Caucasians as compared to other races. Mean alcohol consumption was almost three times higher in males than in females. Undiagnosed hypertension was more common in males than in females, in 65-90 than in 50-64 year olds, and in people with less than high school education compared to those with higher education. Diastolic pressure was correlated with the level of …


Decompositions, Packings, And Coverings Of Complete Directed Gaphs With A 3-Circuit And A Pendent Arc., Chrys Gwellem Aug 2007

Decompositions, Packings, And Coverings Of Complete Directed Gaphs With A 3-Circuit And A Pendent Arc., Chrys Gwellem

Electronic Theses and Dissertations

In the study of Graph theory, there are eight orientations of the complete graph on three vertices with a pendant edge, K3 ∪ {e}. Two of these are the 3-circuit with a pendant arc and the other six are transitive triples with a pendant arc. Necessary and sufficient conditions are given for decompositions, packings, and coverings of the complete digraph with the two 3-circuit with a pendant arc orientations.


Constructing Subdivision Rules From Rational Maps, J. W. Cannon, W. J. Floyd, W. R. Parry Aug 2007

Constructing Subdivision Rules From Rational Maps, J. W. Cannon, W. J. Floyd, W. R. Parry

Faculty Publications

This paper deepens the connections between critically finite rational maps and finite subdivision rules. The main theorem is that if f is a critically finite rational map with no periodic critical points, then for any sufficiently large integer n the iterate f is the subdivision map of a finite subdivision rule. This enables one to give essentially combinatorial models for the dynamics of such iterates.


Pleistocene Peccaries From Guy Wilson Cave, Sullivan County, Tennessee., April Season Nye Aug 2007

Pleistocene Peccaries From Guy Wilson Cave, Sullivan County, Tennessee., April Season Nye

Electronic Theses and Dissertations

Descriptive and taphonomic analyses of undescribed Pleistocene Tayassuidae from Guy Wilson Cave within the East Tennessee State University and McClung Museum collections revealed a MNI of 16 Platygonus compressus and 2 Mylohyus from left femora and isolated teeth, respectively. Linkage between upper dentition and species identification is suggested by comparing Mylohyus fossilis to M. nasutus from other Pleistocene-aged sites. Long-bone NISP and age profiles show a predominance of Platygonus adults. Tayassuidae upper canines, likely Platygonus, suggest sexual dimorphism. Long bones were analyzed for carnivore damage and utilization revealing light utilization similar to that caused by modern wolves. Long bone …


The Shift From Defined Benefit Pensions To 401(K) Plans And The Pension Assets Of The Baby Boom Cohort, James Poterba, Steven Venti, David A. Wise Aug 2007

The Shift From Defined Benefit Pensions To 401(K) Plans And The Pension Assets Of The Baby Boom Cohort, James Poterba, Steven Venti, David A. Wise

Dartmouth Scholarship

The rise of 401(k) plans and the decline of defined benefit plans will have an important effect on the wealth of future retirees. Changing demographic structure also will affect the aggregate stock of retirement wealth. We project the stock of assets held in retirement plans and the average retirement saving of retirees through 2040. Our projections show large increases in wealth at retirement, especially if the returns on corporate equities are comparable with historical returns. Retirement wealth will grow, however, even if equity returns fall substantially below their historical level.