Substructure within the SSA22 protocluster at z≈3.09z\approx3.09

We present the results of a densely sampled spectroscopic survey of the SSA22 protocluster at $z\approx 3.09$. Our sample with Keck/LRIS spectroscopy includes 106 Ly$\alpha$ Emitters (LAEs) and 40 Lyman Break Galaxies (LBGs) at $z=3.05-3.12$. These galaxies are contained within the $9'\times9'$ region in which the protocluster was discovered, which also hosts the maximum galaxy overdensity in the SSA22 region. The redshift histogram of our spectroscopic sample reveals two distinct peaks, at $z=3.069$ (blue, 43 galaxies) and $z=3.095$ (red, 103 galaxies). Furthermore, objects in the blue and red peaks are segregated on the sky, with galaxies in the blue peak concentrating towards the western half of the field. These results suggest that the blue and red redshift peaks represent two distinct structures in physical space. Although the double-peaked redshift histogram is traced in the same manner by LBGs and LAEs, and brighter and fainter galaxies, we find that nine out of 10 X-ray AGNs in SSA22, and all seven spectroscopically-confirmed giant Ly$\alpha$ "blobs," reside in the red peak. We combine our dataset with sparsely sampled spectroscopy from the literature over a significantly wider area, finding preliminary evidence that the double-peaked structure in redshift space extends beyond the region of our dense spectroscopic sampling. In order to fully characterize the three-dimensional structure, dynamics, and evolution of large-scale structure in the SSA22 overdensity, we require the measurement of large samples of LAE and LBG redshifts over a significantly wider area, as well as detailed comparisons with cosmological simulations of massive cluster formation.Comment: 6 pages, 4 figures, Accepted to ApJ Letter

Rural-Urban Cancer Disparities in Mortality: The Role of Physician Supply

Mortality rates are considered to be a marker for a society\u27s overall health and well-being. In the United States, there exist pronounced disparities between urban and rural areas regarding mortality and physician supply. The objective of this research is to ascertain differences in the social determinants of cancer mortality at the county-level, based on level of amenability to treatment in urban and rural areas. Multivariate OLS regression is used to anlayze the associations between demographic, economic, and health predictor variables with more and less amenable mortality, separated by urban and rural distinctions. Results indicate that there are clear differences in the predictors of more and less amenable cancer mortality, especially in rural areas. Non-medical, socioeconomic factors are found to have greater significant impacts on mortality in rural areas more so than urban areas

Male Reproductive Success And The Mating System Of Bushy-tailed Woodrats

Bushy-tailed woodrats are nocturnal cricetid rodents distributed throughout the mountainous regions of western North America. Despite a number of studies on the population ecology of this species, little is known about the behaviour of males during the breeding season.;I investigated the reproductive behaviour of male bushy-tailed woodrats in three ways. First, I examined the spatial distribution of individuals within a breeding population, using radiotelemetry and mark-recapture livetrapping. Both males and females exhibited considerable overlap with animals of both sexes, mean intersexual and intrasexual overlap values for each sex did not differ in two of the three years of study. This pattern of overlap is more indicative of a promiscuous mating system, than of harem polygyny, which had previously been suggested for this species.;Second, I examined the pattern of reproductive success among breeding males, using DNA fingerprinting to determine paternity of all juveniles. No multiple paternity within litters was observed in all years of study. Male woodrats appeared to gain matings by sequestering females throughout estrus, but were unable to restrict access to more that one female at a time. The distribution of male reproductive success, coupled with the spatial overlap of the population, suggests that bushy-tailed woodrats exhibit a roving-male promiscuous mating system.;Third, I investigated the manner in which male woodrats compete for access to females. I examined the relationship between male reproductive success and male characteristics that would be favoured under differing mechanisms of male intrasexual competition. Traits associated with scramble, reproductive endurance, and contest competition showed no significant correlations with reproductive success. However, traits associated with choice by females and sperm competition showed significant correlations with male reproductive success.;I conclude that woodrats exhibit a promiscuous mating system where males attempt to sequester females to ensure paternity of the litters. This male mating strategy is most likely favoured in woodrats due to the short, asynchronous, periods of estrus, and the large, unpredictable, movements of females

Decision Trees

The object of this paper is to inform those concerned with the administration of justice in Ethiopia – particularly, criminal justice – about a new and simple procedure which may assist in procuring uniform interpretation and application of laws and regulations. The problem of uniform interpretation and application is particularly severe where, as in Ethiopia, new laws must be interpreted and applied by persons who have not yet had the opportunity of formal legal education. For these persons the discovery of the relevant code articles and the understanding of their interrelationships and application must be very difficult indeed. One possible result of this unfortunate state of affairs is that the codes will not be fully, effectively, or consistently applied throughout the Empire. If, on the other hand, administrators try to avoid this problem by assigning the Empire\u27s comparatively few legally trained persons to such jobs as public prosecutor, woreda court judge, etc., then the result may be waste of legal resources. No one of these jobs is, in national perspective, of the very greatest importance; overall inefficiency of performance in them, on the other hand, can markedly reduce the quality of Ethiopian justice

Understanding large-scale structure in the SSA22 protocluster region using cosmological simulations

We investigate the nature and evolution of large-scale structure within the SSA22 protocluster region at $z=3.09$ using cosmological simulations. A redshift histogram constructed from current spectroscopic observations of the SSA22 protocluster reveals two separate peaks at $z = 3.065$ (blue) and $z = 3.095$ (red). Based on these data, we report updated overdensity and mass calculations for the SSA22 protocluster. We find $\delta_{b,gal}=4.8 \pm 1.8$, $\delta_{r,gal}=9.5 \pm 2.0$ for the blue and red peaks, respectively, and $\delta_{t,gal}=7.6\pm 1.4$ for the entire region. These overdensities correspond to masses of $M_b = (0.76 \pm 0.17) \times 10^{15} h^{-1} M_{\odot}$, $M_r = (2.15 \pm 0.32) \times 10^{15} h^{-1} M_{\odot}$, and $M_t=(3.19 \pm 0.40) \times 10^{15} h^{-1} M_{\odot}$ for the red, blue, and total peaks, respectively. We use the Small MultiDark Planck (SMDPL) simulation to identify comparably massive $z\sim 3$ protoclusters, and uncover the underlying structure and ultimate fate of the SSA22 protocluster. For this analysis, we construct mock redshift histograms for each simulated $z\sim 3$ protocluster, quantitatively comparing them with the observed SSA22 data. We find that the observed double-peaked structure in the SSA22 redshift histogram corresponds not to a single coalescing cluster, but rather the proximity of a $\sim 10^{15}h^{-1} M_{\odot}$ protocluster and at least one $>10^{14} h^{-1} M_{\odot}$ cluster progenitor. Such associations in the SMDPL simulation are easily understood within the framework of hierarchical clustering of dark matter halos. We finally find that the opportunity to observe such a phenomenon is incredibly rare, with an occurrence rate of 7.4h^3 \mbox{ Gpc}^{-3}.Comment: 13 pages, 8 figures, Accepted to Ap

Post-Disaster Assessment of the Performance of Hazard Mitigation Projects: The California SMART Approach

California\u27s SMART (State Mitigation Assessment Review Team) program for assessing natural hazard mitigation project performance after a disaster is a method of integrating multiple state agencies\u27 expertise into a working tool for assessing the value of public investments in risk reduction. The intent of the SMART program is to provide the California Emergency Management Agency with information about the performance of publicly financed mitigation projects so that it can better allocate future funding and improve the overall safety of California. A key aspect of the program is the mobilization of California State University faculty and staff from across the state after a disaster in order to conduct rapid performance assessments while field data is available. In order to test the SMART system, a pilot study was conducted using the Yountville Flood Barrier Wall Project performance during a 2005 flood on the Napa River. The case validated the idea that for a flood project, a rapid evaluation could be conducted using field observations that establish the height and extent of flooding and include the project\u27s original cost-benefit analysis. The data produced from this type of evaluation program will be valuable to state emergency management agencies trying to allocate program grants in the most efficient manner and to government agencies who want to make sure that federal dollars are being spent wisely