Measuring the Sustainability of U.S. Public Bicycle Systems

As cities worldwide plan for increasing urbanization levels, new challenges in mobility will arise. Any approach taken to address these new issues will need to consider how to move more people with declining resources, thus the need for a sustainable solution arises. This thesis examines the growing trend of cities creating public bicycle systems as a means to add sustainability to a transportation system and identifies what are the criteria and indicators of a sustainable public bicycle. The criteria and indicators are used to examine data collection techniques of three Public Bicycle Systems in the United States: Capital Bikeshare in Washington, D.C., Nice Ride in Minneapolis, Minnesota and Denver B-Cycle in Denver, Colorado

Measuring the Sustainability of U.S. Public Bicycle Systems

As cities worldwide plan for increasing urbanization levels, new challenges in mobility will arise. Any approach taken to address these new issues will need to consider how to move more people with declining resources, thus the need for a sustainable solution arises. This thesis examines the growing trend of cities creating public bicycle systems as a means to add sustainability to a transportation system and identifies what are the criteria and indicators of a sustainable public bicycle. The criteria and indicators are used to examine data collection techniques of three Public Bicycle Systems in the United States: Capital Bikeshare in Washington, D.C., Nice Ride in Minneapolis, Minnesota and Denver B-Cycle in Denver, Colorado

2009 Convocation

Prelude Music: Laura O\u27Neal, 2006 IMSA Graduate; Jonathan Besancon, IMSA Faculty Pledge of Allegiance and Welcome: Sid Sapru, Student Council President; Dr. Max McGee, President; Dr. Eric McLaren, Principal Featured Piece: Laura O\u27Neal, 2006 IMSA Graduate Keynote Speaker: Dr. Tuwanda Williamson, 1991 IMSA Graduat

Multiwavelength Variations of 3C 454.3 during the November 2010 to January 2011 Outburst

We present multiwavelength data of the blazar 3C 454.3 obtained during an extremely bright outburst from November 2010 through January 2011. These include flux density measurements with the Herschel Space Observatory at five submillimeter-wave and far-infrared bands, the Fermi Large Area Telescope at gamma-ray energies, Swift at X-ray, ultraviolet (UV), and optical frequencies, and the Submillimeter Array at 1.3 mm. From this dataset, we form a series of 52 spectral energy distributions (SEDs) spanning nearly two months that are unprecedented in time coverage and breadth of frequency. Discrete correlation anlaysis of the millimeter, far-infrared, and gamma-ray light curves show that the variations were essentially simultaneous, indicative of co-spatiality of the emission, at these wavebands. In contrast, differences in short-term fluctuations at various wavelengths imply the presence of inhomegeneities in physical conditions across the source. We locate the site of the outburst in the parsec-scale core, whose flux density as measured on 7 mm Very Long Baseline Array images increased by 70 percent during the first five weeks of the outburst. Based on these considerations and guided by the SEDs, we propose a model in which turbulent plasma crosses a conical standing shock in the parsec-scale region of the jet. Here, the high-energy emission in the model is produced by inverse Compton scattering of seed photons supplied by either nonthermal radiation from a Mach disk, thermal emission from hot dust, or (for X-rays) synchrotron radiation from plasma that crosses the standing shock. For the two dates on which we fitted the model SED to the data, the model corresponds very well to the observations at all bands except at X-ray energies, where the spectrum is flatter than observed.Comment: Accepted for publication in Astrophysical Journal. 82 pages, 13 figure

Deposit insurance and money market freezes

In the presence of deposit insurance, a rise in counterparty risk may cause a freeze in interbank money markets. We show this in a general equilibrium model with regionally segmented bank-based retail financial markets, in which money markets facilitate the reallocation of funds across banks from different regions. Counterparty risk creates an asymmetry between banks in savings-rich regions, which remain marginally financed by the abundant regional insured deposits, and in savings-poor regions, which have to pay large spreads in money markets. This asymmetry distorts the aggregate allocation of credit and, in the presence of demand externalities, can cause large output losses

Assessing the contribution of recreational sea angling to the English economy

Sea angling has been shown to be a high value activity with significant expenditure by individuals on their sport. Deriving estimates of the economic contribution of recreational sea angling is important in a number of related policy contexts, from tourism management and economic development policy, to the sustainable management of inshore fish stocks. This paper reveals some of the challenges in understanding the economic effects associated with recreational sea angling, and provides estimates of the economic value of recreational sea angling in England. The results were derived from research undertaken in England in 2011- 13, which was conducted as part a wide ranging government-funded study, Sea Angling 2012, that estimated sea angler catches, spending and activity. Recreational sea angling made a significant contribution to the economy, supporting just over £2 billion of total spending, and 23,600 jobs in England in 2012-13. The implications of these results are discussed in the context of the management of recreational sea angling in England

Mammals adjust diel activity across gradients of urbanization

Time is a fundamental component of ecological processes. How animal behavior changes over time has been explored through well-known ecological theories like niche partitioning and predator–prey dynamics. Yet, changes in animal behavior within the shorter 24-hr light–dark cycle have largely gone unstudied. Understanding if an animal can adjust their temporal activity to mitigate or adapt to environmental change has become a recent topic of discussion and is important for effective wildlife management and conservation. While spatial habitat is a fundamental consideration in wildlife management and conservation, temporal habitat is often ignored. We formulated a temporal resource selection model to quantify the diel behavior of 8 mammal species across 10 US cities. We found high variability in diel activity patterns within and among species and species-specific correlations between diel activity and human population density, impervious land cover, available greenspace, vegetation cover, and mean daily temperature. We also found that some species may modulate temporal behaviors to manage both natural and anthropogenic risks. Our results highlight the complexity with which temporal activity patterns interact with local environmental characteristics, and suggest that urban mammals may use time along the 24-hr cycle to reduce risk, adapt, and therefore persist, and in some cases thrive, in human-dominated ecosystems

Relative Stabilities of Conserved and Non-Conserved Structures in the OB-Fold Superfamily

The OB-fold is a diverse structure superfamily based on a β-barrel motif that is often supplemented with additional non-conserved secondary structures. Previous deletion mutagenesis and NMR hydrogen exchange studies of three OB-fold proteins showed that the structural stabilities of sites within the conserved β-barrels were larger than sites in non-conserved segments. In this work we examined a database of 80 representative domain structures currently classified as OB-folds, to establish the basis of this effect. Residue-specific values were obtained for the number of Cα-Cα distance contacts, sequence hydrophobicities, crystallographic B-factors, and theoretical B-factors calculated from a Gaussian Network Model. All four parameters point to a larger average flexibility for the non-conserved structures compared to the conserved β-barrels. The theoretical B-factors and contact densities show the highest sensitivity. Our results suggest a model of protein structure evolution in which novel structural features develop at the periphery of conserved motifs. Core residues are more resistant to structural changes during evolution since their substitution would disrupt a larger number of interactions. Similar factors are likely to account for the differences in stability to unfolding between conserved and non-conserved structures