The Poor and the Dead: Socioeconomic Status and Mortality in the U.S., 1850-1860

Despite the significant research on aggregate trends in mortality and physical stature in the middle of the nineteenth century, little evidence on the individual-level characteristics associated with premature mortality has been presented. This essay describes a new project that links individuals from the mortality schedules to the population schedules of the 1850 and 1860 federal population censuses. This makes it possible to assess the link between individual and household characteristics and the probability of dying. The results reveal a strong and negative relationship between household wealth and mortality in 1850 and 1860 and a somewhat weaker negative relationship between occupational status and mortality in 1850. The findings suggest that even when the U.S. population was largely rural and agricultural, changes in the distribution of income and wealth would have had a large impact on mortality rates and life expectancies. Urbanization merely exacerbated already existing disparities in mortality by socioeconomic status.

The End of American Exceptionalism? Mobility in the U.S. Since 1850

New longitudinal data on individuals linked across nineteenth century U.S. censuses document the geographic and occupational mobility of more than 75,000 Americans from the 1850s to the 1920s. Together with longitudinal data for more recent years, these data make possible for the first time systematic comparisons of mobility over the last 150 years of American economic development, as well as cross-national comparisons for the nineteenth century. The U.S. was a substantially more mobile economy than Britain between 1850 and 1880. But both intergenerational occupational mobility and geographic mobility have declined in the U.S. since the beginning of the twentieth century, leaving much less apparent two aspects of the %u201CAmerican Exceptionalism%u201D noted by nineteenth century observers.

A Tale of Two Labor Markets: Intergenerational Occupational Mobility in Britain and the U.S. Since 1850

The U.S. both tolerates more inequality than Europe and believes its economic mobility is greater than Europe's. These attitudes and beliefs help account for differences in the magnitude of redistribution through taxation and social welfare spending. In fact, the U.S. and Europe had roughly equal rates of inter-generational occupational mobility in the late twentieth century. We extend this comparison into the late nineteenth century using longitudinal data on 23,000 nationally-representative British and U.S. fathers and sons. The U.S. was substantially more mobile then Britain through 1900, so in the experience of those who created the U.S. welfare state in the 1930s, the U.S. had indeed been "exceptional." The margin by which U.S. mobility exceeded British mobility was erased by the 1950s, as U.S. mobility fell compared to its nineteenth century levels.

Death and the City: Chicago's Mortality Transition, 1850-1925

Between 1850 and 1925, the crude death rate in Chicago fell by 60 percent, driven by reductions in infectious disease rates and infant and child mortality. What lessons might be drawn from the mortality transition in Chicago, and American cities more generally? What were the policies that had the greatest effect on infectious diseases and childhood mortality? Were there local policies that slowed the mortality transition? If the transition to low mortality in American cities was driven by forces largely outside the control of local governments (higher per capita incomes or increases in the amount and quality of calories available to urban dwellers from rising agricultural productivity), then expensive public health projects, such as the construction of public water and sewer systems, probably should have taken a back seat to broader national policies to promote overall economic growth. The introduction of pure water explains between 30 and 50 percent of Chicago%u2019s mortality decline, and that other interventions, such as the introduction of the diphtheria antitoxin and milk inspection had much smaller effects. These findings have important implications for current policy debates and economic development strategies.

Combining Computational And Experimental Approaches To Study Disordered And Aggregation Prone Proteins

Over the past two decades disordered proteins have become more widely recognized, challenging the canonical structure-function paradigm associated with proteins. These highly dynamic proteins have been identified across a wide range of species and play a variety of functional roles. Furthermore, the structural plasticity of these proteins gives way to their increased aggregation susceptibility, compared to canonical, well-folded proteins, placing disordered proteins at the center of many neurodegenerative diseases. Despite the increased recognition of the abundance and complexity of disordered proteins, their structural features and the mechanisms by which they transit between functional and pathological roles remains elusive. The efforts described herein focus on leveraging both experimental and computational approaches to study the structure and dynamics of these proteins. Fluorescence-based experiment have proven useful for studying these systems as the intrinsic heterogeneity of this class of proteins, which precludes the use of many traditional structural biochemistry techniques, can be accommodated. Therefore, initial efforts focused on developing new minimally perturbing fluorescence probes and coupling these probes with site-selective labeling strategies. Subsequent efforts focused on identifying methods which could predict where these probes would be tolerated to boost protein yield and avoid structural perturbation. These and other fluorescence probes were employed in Förster Resonance Energy Transfer (FRET) experiments, to study the conformational ensemble of α-synuclein, a disordered protein whose aggregation is implicated in Parkinson’s Disease pathogenesis. Experimental FRET data was paired with molecular modeling in PyRosetta to simulate the conformational ensembles of α-synuclein in the presence and absence of 2 M TMAO. The accuracy of the resultant ensembles was corroborated by comparison to other experimental data. Following this initial success using experimentally constrained simulations, attention was directed towards the development of algorithms capable of generating accurate structural representations of both disordered and ordered proteins de novo. Lastly, this work showcases the utility of a high-throughput in-silico screening approach in identifying a compound that binds selectively to α-synuclein fibrils with nanomolar affinity. Overall this work highlights several computational and experimental approaches which are broadly applicable to the study of disordered and aggregation prone protein

Efficient simulation scheme for a class of quantum optics experiments with non-negative Wigner representation

We provide a scheme for efficient simulation of a broad class of quantum optics experiments. Our efficient simulation extends the continuous variable Gottesman-Knill theorem to a large class of non-Gaussian mixed states, thereby identifying that these non-Gaussian states are not an enabling resource for exponential quantum speed-up. Our results also provide an operationally motivated interpretation of negativity as non-classicality. We apply our scheme to the case of noisy single-photon-added-thermal-states to show that this class admits states with positive Wigner function but negative P -function that are not useful resource states for quantum computation.Comment: 14 pages, 1 figur

Negative Quasi-Probability as a Resource for Quantum Computation

A central problem in quantum information is to determine the minimal physical resources that are required for quantum computational speedup and, in particular, for fault-tolerant quantum computation. We establish a remarkable connection between the potential for quantum speed-up and the onset of negative values in a distinguished quasi-probability representation, a discrete analog of the Wigner function for quantum systems of odd dimension. This connection allows us to resolve an open question on the existence of bound states for magic-state distillation: we prove that there exist mixed states outside the convex hull of stabilizer states that cannot be distilled to non-stabilizer target states using stabilizer operations. We also provide an efficient simulation protocol for Clifford circuits that extends to a large class of mixed states, including bound universal states.Comment: 15 pages v4: This is a major revision. In particular, we have added a new section detailing an explicit extension of the Gottesman-Knill simulation protocol to deal with positively represented states and measurement (even when these are non-stabilizer). This paper also includes significant elaboration on the two main results of the previous versio