Legislating Market Winners: Digital Signature Laws and the Electronic Commerce Marketplace

The author argues that certain enacted digital signature laws are premised upon false assumptions, and inappropriately enshrine a business model which would not naturally evolve in the marketplace. In attempting to solve an unsolvable liability allocation problem, such legislation harms consumers and the future evolution of electronic commerce. This article points out that alternative business models can solve the liability allocation problem. Despite obvious flaws, legislation of this kind continues to be proposed, partly because the infrastructure created by these laws coincides with the needs of key escrow proponents. Ultimately the article argues that digital signature laws, which impose a particular view of electronic commerce, should be abandoned, in favor of laws, which remove specific, well-defined barriers to electronic commerce, and which allow the electronic commerce marketplace to evolve unfettered

Expanding and evaluating sense codon reassignment for genetic code expansion

2017 Summer.Includes bibliographical references.Genetic code expansion is a field of synthetic biology that aims to incorporate non-canonical amino acids (ncAAs) into proteins as though they were one of the 20 "natural" amino acids. The amino acids which naturally make up proteins are chemical limited, and ncAAs can carry new chemical functionality into proteins. Proteins are of interest because they are simple to produce with good consistency and have immense potential due to the diversity of structure and function. Incorporating ncAA into proteins expands the scope of function of proteins even further. Two methods have been widely used for genetic code expansion, global amino acid replacement and amber stop codon suppression. Global amino acid replacement exchanges one of the natural amino acids for a ncAA, producing an altered 20 amino acid genetic code. Amber stop codon suppression incorporates ncAA in response to the UAG stop codon making a 21 amino acid genetic code, but is limited in incorporation efficiency and producing proteins with multiple instances of a ncAA is challenging. We wanted to use a third genetic code expansion system called sense codon reassignment which has not been widely employed at all but should enable multisite incorporation of ncAAs. When the work presented in this dissertation was started, a single report of sense codon reassignment existed in the literature. We set out to improve and expand sense codon reassignment for the incorporation of multiple copies of ncAAs into proteins. We quickly discovered disparities in what was known regarding the variables that could be used to manipulate genetic code expansion, and the focus of our work shifted to systems for improving sense codon reassignment using quantitative measurements. The first chapter of this dissertation is an introduction to genetic code expansion and the processes of translation and gene expression that are likely involved or could be involved in genetic code expansion. The three following chapters will build upon the fundamentals described in Chapter 1. The second chapter is a complete story about how a screen to quantify sense codon reassignment was developed. The fluorescence based screen was used in a high throughput fashion to screen a directed evolution library of variants for increased sense codon reassignment efficiency at the Lys AAG sense codon. While evaluating various sense codons for potential reassignment efficiency, the AUG anticodon was found to be incapable of discriminating between the CAU and CAC codons. This was anomalous relative to the other anticodons we tested. Chapter 3 describes how unintended modifications to an engineered tRNA were identified and then how the fluorescence based screen was used to engineer the tRNA further for increased sense codon reassignment efficiency and to avoid the unintentional modification. Most applications of genetic code expansion rely on modifications to tRNAs but few reports actually consider them, The final chapter of this dissertation is a manuscript in preparation describing the reassignment of a rare sense codon to incorporate ncAAs. The chapter focuses on how improvements made in a system specific for an amino acid can be transferred to systems specific for other ncAAs. Over 150 different ncAAs have been incorporated into proteins using genetic code expansion technologies, but the extent to which the various systems are combinable has barely been evaluated. This dissertation is a story about developing sense codon reassignment to functional levels and quantifying the effects of different variables along the way

Misplaced Priorities: The Utah Digital Signature Act and Liability Allocation in a Public Key Infrastructure

This Comment examines the Utah Digital Signature Act, signed into law on March 9, 1995. The Utah Act promotes the use of digital signatures on computer-based documents. This Comment analyzes the allocation of liability and evidentiary burdens imposed by the Utah Act, and compares these provisions to three analogous models. The author asserts that the liability allocations of the Utah Act inappropriately impose potentially unlimited risk on users of digital signatures. He also suggests an alternative approach to the apportionment of liability in a public key infrastructure

School-Community Partnerships in Maine

This study examined six diverse school districts in Maine that have successfully formed partnerships between their districts and community or regional organizations to expand supports to students and their families that go beyond academic support to include health, mental health, social services and other supports

Liability of Foreignness in Global Stock Markets: Liquidity Dynamics of Foreign IPOs in the US

Using a unique dataset of foreign and domestic IPOs listings in the US from 1990 to 2012, we study how foreignness affects IPO liquidity. We find that foreign IPOs enjoy higher liquidity than IPOs in their home countries, but do not fully gain the same liquidity benefits as for IPOs of domestic US issuers. In contrast to prior evidence for mature cross-listed firms, we show that liquidity differentials between foreign and domestic IPOs in the US are determined by information asymmetry related to foreignness rather than to home-country institutional environment characteristics. Thus, our results extend prior findings to reveal salient differences in liquidity and liquidity determinants between IPOs offerings by foreign and domestic firms in the US.postprin

Upper ocean distribution of glacial meltwater in the Amundsen Sea, Antarctica

Pine Island Ice Shelf, in the Amundsen Sea, is losing mass due to increased heat transport by warm ocean water penetrating beneath the ice shelf and causing basal melt. Tracing this warm deep water and the resulting glacial meltwater can identify changes in melt rate and the regions most affected by the increased input of this freshwater. Here, optimum multi‐parameter analysis is used to deduce glacial meltwater fractions from independent water mass characteristics (standard hydrographic observations, noble gases and oxygen isotopes), collected during a ship‐based campaign in the eastern Amundsen Sea in February‐March 2014. Noble gases (neon, argon, krypton and xenon) and oxygen isotopes are used to trace the glacial melt and meteoric water found in seawater and we demonstrate how their signatures can be used to rectify the hydrographic trace of glacial meltwater, which provides a much higher resolution picture. The presence of glacial meltwater is shown to mask the Winter Water properties, resulting in differences between the water mass analyses of up to 4 g kg−1 glacial meltwater content. This discrepancy can be accounted for by redefining the ”pure” Winter Water endpoint in the hydrographic glacial meltwater calculation. The corrected glacial meltwater content values show a persistent signature between 150 ‐ 400 m of the water column across all of the sample locations (up to 535 km from Pine Island Ice Shelf), with increased concentration towards the west along the coastline. It also shows, for the first time, the signature of glacial meltwater flowing off‐shelf in the eastern channel