PRESENT TRENDS IN POPULATION DISTRIBUTION

Labor and Human Capital,

THE ROLE OF TRANSPORTATION IN POPULATION DISTRIBUTION

Public Economics,

Linking Stochastic Dynamics to Population Distribution: An Analytical Framework of Gene Expression

We present an analytical framework describing the steady-state distribution of protein concentration in live cells, considering that protein production occurs in random bursts with an exponentially distributed number of molecules. We extend this framework for cases of transcription autoregulation and noise propagation in a simple genetic network. This model allows for the extraction of kinetic parameters of gene expression from steady-state distributions of protein concentration in a cell population, which are available from single cell data obtained by flow cytometry or fluorescence microscopy

Measurement of the Mass and Stellar Population Distribution in M82 with the LBT

We present a K-band spectroscopic study of the stellar and gas kinematics, mass distribution, and stellar populations of the archetypical starburst galaxy M82. Our results are based on a single spectrum at a position angle of 67.5 degrees through the K-band nucleus. We used the CO stellar absorption band head at 2.29 {\mu}m (CO_2.29) to measure the rotation curve out to nearly 4 kpc radius on both the eastern and western sides of the galaxy. Our data show that the rotation curve is flat from 1 - 4 kpc. This stands in sharp contrast to some previous studies, which have interpreted H I and CO emission-line position-velocity diagrams as evidence for a declining rotation curve. The kinematics of the Br\gamma, H_2, and He I emission lines are consistent with, although characterized by slightly higher velocities than, the stellar kinematics. We derived M82's mass distribution from our stellar kinematic measurements and estimate its total dynamical mass is ~10^10 Msun. We measured the equivalent width of CO_2.29 (W_2.29) as a function of distance from the center of the galaxy to investigate the spatial extent of the red supergiant (RSG) population. The variation in W_2.29 with radius clearly shows that RSGs dominate the light inside 500 pc radius. M82's superwind is likely launched from this region, where we estimate the enclosed mass is <= 2 x 10^9 Msun.Comment: 6 pages, 6 figures. Submitted to ApJ. For a brief video explaining the key result of this paper, see http://www.youtube.com/user/OSUAstronom

Pressure effects on bimolecular recombination and unimolecular dissociation reactions

The treatment of pressure effects on bimolecular recombinations and unimolecular dissociations is discussed. The analysis of recombination and dissociation reactions is made by showing how the nonequilibrium energy (E) and angular momentum (J)-dependent steady-state population distribution functions for the two reactions are related to each other and to the equilibrium population distribution function at the given E and J. As a special case a strong collision model is then used for the collisional rotational angular momentum transfer, and a ladder model for the collisional energy transfer. An analytical result is obtained for states below the dissociation threshold. The extension to recombinations with two exit channels is described, for application to ozone formation and isotopic effects

Transfers of capital and shifts in New Zealand’s regional population distribution, 1840-1996

When researchers attempt to study population and development, and particularly the role of migrations, the focus is normally on national level trends, frequently involving time-series analyses of more generic indicators of population change and economic growth. The migration field does, of course, deal with questions of the integration of migrants, at a macro-level evaluating their impact on social diversity and cohesion by turning to ecological-level indices covering clustering. This paper takes a different approach in part inspired by the model developed by Le Heron, Britton and Parson to analyse a related question: restructuring. This they saw as likely to be induced and thus frequently exogenous to a particular socio-demographic system. For example, policies effecting restructuring at a regional level will often come from some central agency external to the region, or even outside the geographic territory or country. There are also other changes that can be spontaneous in nature, arising from a mix of factors and situations endogenous to a given area.1 In both cases, so these authors argue (1992:5), we must deal with “processes operating at various geographic scales...”. To this end this paper thus employs as demographic variables indices plotting subnational changes, thereby recognising that population dynamics at the national-level are likely to be a composite of complex societal forces varying from region to region. For much of this essay, which is more an exercise in setting research agendas than a full-scale empirical analysis, the regional breakdown is very broad, attempting to distinguish between the more dominant and less dominant poles at any time

LAND USE, POPULATION DISTRIBUTION, AND EXPENDITURES IN LOCAL GOVERNMENTS OF MICHIGAN

Land Economics/Use, Public Economics,

All-optical reconstruction of atomic ground-state population

The population distribution within the ground-state of an atomic ensemble is of large significance in a variety of quantum optics processes. We present a method to reconstruct the detailed population distribution from a set of absorption measurements with various frequencies and polarizations, by utilizing the differences between the dipole matrix elements of the probed transitions. The technique is experimentally implemented on a thermal rubidium vapor, demonstrating a population-based analysis in two optical pumping examples. The results are used to verify and calibrate an elaborated numerical model, and the limitations of the reconstruction scheme which result from the symmetry properties of the dipole matrix elements are discussed.Comment: 6 pages, 4 figure

The Integration of Immigrants and Their Families in Maryland: A Look at Children of Immigrants and Their Families in Maryland

Analyzes the population, distribution, origins, family structure, and school readiness and performance of children with at least one foreign-born parent, as well as parents' education, income, homeownership, and public benefit use. Explores implications