Resolving 3D Disk Orientation using High-Resolution Images: New Constraints on Circumgalactic Gas Inflows

We constrain gas inflow speeds in star-forming galaxies with color gradients consistent with inside-out disk growth. Our method combines new measurements of disk orientation with previously described circumgalactic absorption in background quasar spectra. Two quantities, a position angle and an axis ratio, describe the projected shape of each galactic disk on the sky, leaving an ambiguity about which side of the minor axis is tipped toward the observer. This degeneracy regarding the 3D orientation of disks has compromised previous efforts to measure gas inflow speeds. We present HST and Keck/LGSAO imaging that resolves the spiral structure in five galaxies at redshift $z\approx0.2$. We determine the sign of the disk inclination for four galaxies, under the assumption that spiral arms trail the rotation. We project models for both radial infall in the disk plane and circular orbits onto each quasar sightline. We compare the resulting line-of-sight velocities to the observed velocity range of Mg II absorption in spectra of background quasars, which intersect the disk plane at radii between 69 and 115 kpc. For two sightlines, we constrain the maximum radial inflow speeds as 30-40 km s$^{-1}$. We also rule out a velocity component from radial inflow in one sightline, suggesting that the structures feeding gas to these growing disks do not have unity covering factor. We recommend appropriate selection criteria for building larger samples of galaxy--quasar pairs that produce orientations sensitive to constraining inflow properties.Comment: 15 pages with 8 figures and 2 tables; accepted for publication in Ap

Geospatial modeling approach to monument construction using Michigan from A.D. 1000–1600 as a case study

Building monuments was one way that past societies reconfigured their landscapes in response to shifting social and ecological factors. Understanding the connections between those factors and monument construction is critical, especially when multiple types of monuments were constructed across the same landscape. Geospatial technologies enable past cultural activities and environmental variables to be examined together at large scales. Many geospatial modeling approaches, however, are not designed for presence-only (occurrence) data, which can be limiting given that many archaeological site records are presence only. We use maximum entropy modeling (MaxEnt), which works with presence-only data, to predict the distribution of monuments across large landscapes, and we analyze MaxEnt output to quantify the contributions of spatioenvironmental variables to predicted distributions. We apply our approach to co-occurring Late Precontact (ca. A.D. 1000–1600) monuments in Michigan: (i) mounds and (ii) earthwork enclosures. Many of these features have been destroyed by modern development, and therefore, we conducted archival research to develop our monument occurrence database. We modeled each monument type separately using the same input variables. Analyzing variable contribution to MaxEnt output, we show that mound and enclosure landscape suitability was driven by contrasting variables. Proximity to inland lakes was key to mound placement, and proximity to rivers was key to sacred enclosures. This juxtaposition suggests that mounds met local needs for resource procurement success, whereas enclosures filled broader regional needs for intergroup exchange and shared ritual. Our study shows how MaxEnt can be used to develop sophisticated models of past cultural processes, including monument building, with imperfect, limited, presence-only data

Speech Communication

Contains reports on one research project.Air Force Cambridge Research Laboratories, Office of Aerospace Research, U. S. Air Force, under Contract AF19(628)-3325National Science Foundation (Grant GP-2495)National Institutes of Health (Grant NB-04332-02)National Institutes of Health (Grant MH-04737-05)National Aeronautics and Space Administration (Grant NsG-496

Palm phytoliths of mid-elevation Andean forests

Palms are one of the most common tropical plant groups. They are widespread across lowland tropical forests, but many are found in higher altitudes have more constrained environmental ranges. The limited range of these species makes them particularly useful in paleoecological and paleoclimate reconstructions. Palms produce phytoliths, or silica structures, which are found in their vegetative parts (e.g., wood, leaves, etc.). Recent research has shown that several palms in the lowland tropical forests produce phytoliths that are diagnostic to the sub-family or genus-level. Here we characterize Andean palm phytoliths, and determine whether many of these species can also be identified by their silica structures. All of our sampled Andean palm species produced phytoliths, and we were able to characterize several previously unclassified morphotypes. Some species contained unique phytoliths that did not occur in other species, particularly Ceroxylon alpinium, which is indicative of specific climatic conditions. The differences in the morphologies of the Andean species indicate that palm phytolith analysis is particularly useful in paleoecological reconstructions. Future phytolith analyses will allow researchers to track how these palm species with limited environmental ranges have migrated up and down the Andean slopes as a result of past climatic change. The phytolith analyses can track local-scale vegetation dynamics, whereas pollen, which is commonly used in paleoecological reconstructions, reflects regional-scale vegetation change

Nebraska Serious and Violent Offender Re-entry Program: An Evaluation of Participants\u27 Perception of Program Effectiveness

In response to the three-fold increase in the number of returning inmates to America\u27s communities over the last three decades, the Department of Justice\u27s Serious and Violent Offender Re-entry Initiative provides funding for development of programming to reduce recidivism rates and improve community safety. However, evaluations of these re-entry programs have not addressed the attitudes and opinions of the program participants themselves. This study examined the perceptions of the re-entry participants to help assess the effectiveness of the programming they are receiving from the Nebraska Serious and Violent Offender Re-entry Pilot Program. Data was gathered from personalized re-entry plans for offenders and through qualitative interviews of the program transition managers and program participants. The results of this research addressed the effectiveness and possible improvements of the Nebraska re-entry program, which will ultimately affect the inmates\u27 likelihood of living crime-free upon their return to the community and hence increase public safety

Kinematics of Circumgalactic Gas: Feeding Galaxies and Feedback

We present observations of 50 pairs of redshift z ~ 0.2 star-forming galaxies and background quasars. These sightlines probe the circumgalactic medium (CGM) out to half the virial radius, and we describe the circumgalactic gas kinematics relative to the reference frame defined by the galactic disks. We detect halo gas in MgII absorption, measure the equivalent-width-weighted Doppler shifts relative to each galaxy, and find that the CGM has a component of angular momentum that is aligned with the galactic disk. No net counter-rotation of the CGM is detected within 45 degrees of the major axis at any impact parameter. The velocity offset of the circumgalactic gas correlates with the projected rotation speed in the disk plane out to disk radii of roughly 70 kpc. We confirm previous claims that the MgII absorption becomes stronger near the galactic minor axis and show that the equivalent width correlates with the velocity range of the absorption. We cannot directly measure the location of any absorber along the sightline, but we explore the hypothesis that individual velocity components can be associated with gas orbiting in the disk plane or flowing radially outward in a conical outflow. We conclude that centrifugal forces partially support the low-ionization gas and galactic outflows kinematically disturb the CGM producing excess absorption. Our results firmly rule out schema for the inner CGM that lack rotation and suggest that angular momentum as well as galactic winds should be included in any viable model for the low-redshift CGM.Comment: Accepted for publication in the Astrophysical Journa

Onciderini Thomson, 1860 (Coleoptera: Cerambycidae: Lamiinae) types of the Field Museum of Natural History (FMNH), with a brief history of the Coleoptera collection

The primary types of Onciderini Thomson, 1860 of the Field Museum of Natural History (FMNH) are catalogued and illustrated. Data on the original combination, current name, gender, and type locality are verifi ed and presented. There are 14 primary types of Onciderini including fi ve in Oncideres Lacordaire, 1830; three in Charoides Dillon and Dillon, 1945; and two in Jamesia Jekel, 1861. Of the 14 primary types, 13 were described by L.S. Dillon and E.S. Dillon. One lectotype is designated. A brief history of the Coleoptera collection at the FMNH is also presented

THE SELF-EXPRESSIVENESS OF FOOTPRINTS: UNDERSTANDING THE DRIVERS OF CHECK-IN

Drawing from the Dramaturgical theory (Goffman, 1959), present study contributes to propose a conceptual model that illuminate the underlying psychological mechanism which faciliate individual’s check-in behavior. Goffman (1959) posits that “impression management” impacts the self presentation of individuals, indicating that individuals adopt deliberate decisions to reveal particular aspects of the self. Past studies emphasize on the privacy issue that impacts location sharing (Barkhuus et al., 2008), while present study highlights that socially driven factors portrays a more comprehensive story that disclose the antecedenting drivers of check-in.This contributes in providing a framework to the previous sporadic studies concerning social motives in check-in literatures. Specifically, the findings support the view that individual’s public self-consciousness and peer influence, compelled by desirable self-presentation leads to involvment in check-in. This finding extends past researches in identifying two dimensions that drive check-in involvement. Furthermore, the results of this study confirm that driven by psychological proximity, a positive relationship is created between check-in involvement and place attachment, which in turn faciliates continual check-in behavioral intentions and the advocation of check-in

Drivers of Online Brand Community Value Creation: The Role of Psychological Empowerment

There is an upsurge of consumer empowerment driven by the rise of the Internet and online communities. However, the effect of psychological empowerment that may be experienced in contributing knowledge and experiences in the process of participation in online brand community has seldom been investigated. This study aims to examine the role of psychological empowerment in online brand community and its impact on value co-creation behaviors. By using PLS-SEM, the result indicate that perceived responsiveness, validation, status seeking, perceived network size, and information quality, facilitates the establishment of psychological empowerment, which in turn promotes consumers’ value co-creation behaviors. Implications for researchers and practitioners are discussed