Beef-cattle production functions in forage utilization

Little information has existed on substitution rates between pasture forages and corn in a beef-fattening enterprise. Without this knowledge it is difficult to determine which combinations of pasture forage and com would maximize profits. Profits in feeding depend not only on the cost of feed but also on the time of marketing. The pasture forage-corn ration that minimizes costs may not necessarily be the ration that maximizes profits, since profits are affected by the time of marketing. Both the quality and the price of beef are subject to change during the beef-fattening period. Consequently, the beef-cattle feeder is confronted with the problem of selecting (a) the least-cost pasture forage-corn ration (b) that will place the beef cattle on the market finished to a grade (c) at the time when the expected market price will maximize profits. A beef-feeding experiment was designed to determine the feed relationships between soilage (fresh-chopped pasture forage) and com. It was conducted at two locations over a period of 3 years -1957, 1958 and 1959. Six different soilage-corn rations, ranging from all soilage to 2 parts soilage and 1 part corn, were fed to different lots of feeder steers at each location. The rations at each location were also fortified with a feed supplement. Stilbestrol was included in the rations at one of the locations. The results of this feeding experiment are based on the performance of 336 head of good-to-choice feeder steers

Calcitonin receptor N-glycosylation enhances peptide hormone affinity by controlling receptor dynamics

The class B G protein-coupled receptor (GPCR) calcitonin receptor (CTR) is a drug target for osteoporosis and diabetes. N-glycosylation of asparagine 130 in its extracellular domain (ECD) enhances calcitonin hormone affinity with the proximal GlcNAc residue mediating this effect through an unknown mechanism. Here, we present two crystal structures of salmon calcitonin-bound, GlcNAc-bearing CTR ECD at 1.78 and 2.85 Å resolutions and analyze the mechanism of the glycan effect. The N130 GlcNAc does not contact the hormone. Surprisingly, the structures are nearly identical to a structure of hormone-bound, N-glycan-free ECD, which suggested that the GlcNAc might affect CTR dynamics not observed in the static crystallographic snapshots. Hydrogen-deuterium exchange mass spectrometry and molecular dynamics simulations revealed that glycosylation stabilized a β-sheet adjacent to the N130 GlcNAc and the N-terminal α-helix near the peptide-binding site, while increasing flexibility of the peptide-binding site turret loop. These changes due to N-glycosylation increased the ligand on-rate and decreased its off rate. The glycan effect extended to RAMP-CTR amylin receptor complexes and was also conserved in the related CGRP receptor. These results reveal that N-glycosylation can modulate GPCR function by altering receptor dynamics

Abstract digital computers and automata

Ph.D

States of Disunion: American Marriage and Divorce, 1867–1906

This dissertation comprises three essays on the historical relationship between capitalist development, state formation and marriage and divorce patterns in the United States.The first examines the effects of liberalizing women’s property rights on divorce. In the late nineteenth century, most American states gave married women new rights to own and control assets and earnings. Using administrative data on most U.S. divorces between 1867 and 1906, I show that rights transfers gave women financial independence from husbands that enabled them to exit undesirable unions at greater rates. However, husbands also filed for more divorces following women’s economic gains, suggesting that the violation of traditional gender norms of household governance also destabilized unions.The second essay explores the legal behavior of men and women who faced significant restrictions on divorce. Before the 1970s, U.S. states allowed legal divorces only for specified causes. Examining data on the causes cited by divorce seekers, I document the routinization of divorce procedure over historical time. I also exploit legal changes to demonstrate that individuals adapted to divorce regulations by changing the causes they cited. Strategic legal behavior was widespread but differed by gender, with men being more prone toward routinization and women being more likely to adapt to new rules. The third essay reflects critically on the quality of available data on nineteenth-century marriages. I compare vital records of marriages to census microdata on marital duration, showing that the latter exhibit significant measurement error. Despite growing interest by elite state actors in measuring marriage and divorce at the population level, vital recording, which had administrative origins in the clarification of individual legal statuses, seems to have elicited more reliable participation in official knowledge projects. I analyze the extent and distribution of mismeasurement, which has consequences for both the study of American political development and the validity of quantitative historical research on the family