Testing and Data Recovery Excavations at Prehistoric Occupation Site 41HR1114, Harris County, Texas

This report documents the National Register significance testing and data recovery investigations conducted from February 27-March 15, 2012 (testing), and June 11-25, 2012 (data recovery), at the site of 41HR1114 by Moore Archeological Consulting, Inc. The site is located just west of Lower Mayde Creek, in west Harris County, Texas. The site had been first located during a February, 2012 survey conducted by Moore Archeological Consulting, Inc. in preparation for a proposed extension of the Park Row Boulevard Right-of-Way (Moore and Driver 2012). The survey alignment was privately owned at the time of the survey, and therefore, neither the Antiquities Code of Texas nor Section 106 of the National Historic Preservation Act of 1966 mandated the survey. However, the survey was carried out as proactive due diligence as a key element of the future regulatory requirements for a private development project on an ambitious development schedule. The survey identified three sites, 41HR1114, 41HR1115, and 41HR1116. Significance testing excavations at 41HR1114 were conducted in February and March, 2012, and were also carried out as proactive due diligence. The test excavations consisted of hand excavation and backhoe trenching with a focus on geomorphological assessment of the site, including the depositional reconstruction and identification of the degree of intactness of the deposits. These investigations determined that the site possessed the potential for future research, and should be considered eligible for listing on the National Register of Historic Places (NRHP). At that point, the development project was subsumed within the Harris County Improvement District No. 4, DBA Energy Corridor Management District, and further investigations fell under the jurisdiction of the Texas Historic Commission (THC) permitting process. To facilitate planned development schedules, the proposed Park Row Boulevard Right-of-Way alignment was divided into smaller segments, with 41HR1114 located in the Phase 1 segment. This portion of the alignment measures approximately 850 m (2800 ft) in length, and the area of potential effect (APE) in the area of 41HR1114 is limited to a 36.5 m (120 ft) wide ROW (Figure 1). The data recovery investigations at 41HR1114 were conducted under Texas Antiquities Permit Number 6274. During the significance testing and data recovery field investigations at 41HR1114, a total of sixteen 1 x 1 m hand units (XU 1-16) were excavated. XUs 1-4 were conducted as distinct 1 x 1 m units (XUs 1, 2, and 4 were placed adjacent to backhoe trenches) during the testing phase, while the remainder of the hand excavations were conducted as two 2 x 3 m block excavations (subdivided into XUs 5-10 and 11-16) as part of the data recovery phase. Three backhoe trenches (BHTs 1-3) totaling 45 m in length were excavated, two during the testing phase and one during the data recovery operations. The excavations produced a total of 4431 artifacts. These materials were recovered from Levels 1-14 (0-150 cmbs), but with the highest concentrations of artifacts encountered in Levels 3-7. The chronologically diagnostic dart point types, in conjunction with the presence of ceramics and the lack of arrow points, indicate occupations at the site spanning the Middle Archaic to Early Ceramic periods. However, the vertical distribution of diagnostic artifacts and the geoarchaeological assessment of the site deposits indicate the presence of significant bioturbation-related disturbance of cultural materials located throughout the site. Consequently, the real, and quite significant contribution of this project is instead, the intensive geoarcheological analysis of the Late Pleistocene and Early Holocene alluvium and of the nature and appearance of soil formation within such deposits at the site, and by extension for the Houston area. The current investigation has considerably diminished the paucity of information on the deposits lain down by small streams in the region, as well as provided insight into the pedogenic processes associated with argillic horizons in the late Pleistocene and Holocene soils of Southeast Texas. We may conclude by reiterating that the Data Recovery excavations at 41HR1114 were successful in providing new information on the prehistory of the site and the broader Houston region. The contribution from the strictly archeological analysis of the cultural materials and contexts yielded by the site are modest. In contrast, the results of the intensive geoarcheological analysis of the site are quite novel and important, and have considerable broader application in the future analysis and evaluation of prehistoric sites within the Houston region. No further archeological work is recommended for 41HR1114. Once the current report is finalized, the artifacts recovered from 41HR1114 will be curated at TARL

Continuous Time Structural Equation Modeling with R Package ctsem

We introduce ctsem, an R package for continuous time structural equation modeling of panel (N > 1) and time series (N = 1) data, using full information maximum likelihood. Most dynamic models (e.g., cross-lagged panel models) in the social and behavioural sciences are discrete time models. An assumption of discrete time models is that time intervals between measurements are equal, and that all subjects were assessed at the same intervals. Violations of this assumption are often ignored due to the difficulty of accounting for varying time intervals, therefore parameter estimates can be biased and the time course of effects becomes ambiguous. By using stochastic differential equations to estimate an underlying continuous process, continuous time models allow for any pattern of measurement occasions. By interfacing to OpenMx, ctsem combines the flexible specification of structural equation models with the enhanced data gathering opportunities and improved estimation of continuous time models. ctsem can estimate relationships over time for multiple latent processes, measured by multiple noisy indicators with varying time intervals between observations. Within and between effects are estimated simultaneously by modeling both observed covariates and unobserved heterogeneity. Exogenous shocks with different shapes, group differences, higher order diffusion effects and oscillating processes can all be simply modeled. We first introduce and define continuous time models, then show how to specify and estimate a range of continuous time models using ctsem

Dynamics of adolescents' smartphone use and well-being are positive but ephemeral

Well-being and smartphone use are thought to influence each other. However, previous studies mainly focused on one direction (looking at the effects of smartphone use on well-being) and considered between-person effects, with self-reported measures of smartphone use. By using 2548 assessments of well-being and trace data of smartphone use collected for 45 consecutive days in 82 adolescent participants (M$_{age}$ = 13.47, SD$_{age}$ = 1.62, 54% females), the present study disentangled the reciprocal and individual dynamics of well-being and smartphone use. Hierarchical Bayesian Continuous Time Dynamic Models were used to estimate how a change in frequency and duration of smartphone use predicted a later change in well-being, and vice versa. Results revealed that (i) when participants used the smartphone frequently and for a longer period, they also reported higher levels of well-being; (ii) well-being positively predicted subsequent duration of smartphone use; (iii) usage patterns and system dynamics showed heterogeneity, with many subjects showing reciprocal effects close to zero; finally, (iv) changes in well-being tend to persist longer than changes in the frequency and duration of smartphone use

Dynamic modeling of practice effects across the healthy aging-Alzheimer’s disease continuum

Standardized tests of learning and memory are sensitive to changes associated with both aging and superimposed neurodegenerative diseases. Unfortunately, repeated behavioral test administration can be confounded by practice effects (PE), which may obscure declines in level of abilities and contribute to misdiagnoses. Growing evidence, however, suggests PE over successive longitudinal measurements may differentially predict cognitive status and risk for progressive decline associated with aging, mild cognitive impairment (MCI), and dementia. Thus, when viewed as a reflection of neurocognitive plasticity, PE may reveal residual abilities that can add to our understanding of age- and disease-related changes in learning and memory. The present study sought to evaluate differences in PE and verbal recall in a clinically characterized aging cohort assessed on multiple occasions over 3 years. Participants included 256 older adults recently diagnosed as cognitively unimpaired (CU; n = 126), or with MCI of amnestic (n = 65) or non-amnestic MCI (n = 2085), and multi-domain amnestic dementia of the Alzheimer’s type (DAT; n = 45). We applied a continuous time structural equation modeling (ctsem) approach to verbal recall performance on the Hopkins Verbal Learning Test in order to distinguish PE from individual occasion performance, coupled random changes, age trends, and differing measurement quality. Diagnoses of MCI and dementia were associated with lower recall performance on all trials, reduced PE gain per occasion, and differences in non-linear dynamic parameters. Practice self-feedback is a dynamic measure of the decay or acceleration in PE process changes over longitudinal occasions. As with PE and mean recall, estimated practice self-feedback followed a gradient from positive in CU participants to null in participants with diagnosed MCI and negative for those with dementia diagnoses. Evaluation of sensitivity models showed this pattern of variation in PE was largely unmodified by differences in age, sex, or educational attainment. These results show dynamic modeling of PE from longitudinal performance on standardized learning and memory tests can capture multiple aspects of behavioral changes in MCI and dementia. The present study provides a new perspective for modeling longitudinal change in verbal learning in clinical and cognitive aging research

The Faint End Slopes Of Galaxy Luminosity Functions In The COSMOS 2-Square Degree Field

We examine the faint-end slope of the rest-frame V-band luminosity function (LF), with respect to galaxy spectral type, of field galaxies with redshift z<0.5, using a sample of 80,820 galaxies with photometric redshifts in the Cosmic Evolution Survey (COSMOS) field. For all galaxy spectral types combined, the LF slope, alpha, ranges from -1.24 to -1.12, from the lowest redshift bin to the highest. In the lowest redshift bin (0.02<z<0.1), where the magnitude limit is M(V) ~ -13, the slope ranges from ~ -1.1 for galaxies with early-type spectral energy distributions (SEDs), to ~ -1.9 for galaxies with low-extinction starburst SEDs. In each galaxy SED category (Ell, Sbc, Scd/Irr, and starburst), the faint-end slopes grow shallower with increasing redshift; in the highest redshift bin (0.4<z<0.5), the slope is ~ -0.5 and ~ -1.3 for early-types and starbursts respectively. The steepness of alpha at lower redshift could be qualitatively explained by large numbers of faint dwarf galaxies, perhaps of low surface brightness, which are not detected at higher redshifts.Comment: 24 pages including 5 figures, accepted to ApJ

On the dynamics of social hierarchy: A longitudinal investigation of the rise and fall of prestige, dominance, and social rank in naturalistic task groups

The pursuit of social rank pervades all human societies and the position that an individual occupies within a hierarchy has important effects on their social and reproductive success. Whilst recent research has indicated that there are two distinct routes to rank attainment—dominance (through the induction of fear) and prestige (through respect and admiration)—this empirical evidence has generally provided only a cross-sectional snapshot of how the two processes operate in human hierarchy. Whether dominance and prestige are potentially viable long-term strategies, rather than more effective short-term tactics, for acquiring rank in groups remains an open question. The current research addresses this gap by examining the temporal dynamics between prestige, dominance and social rank using a dynamic, evolutionary approach to understanding human social hierarchy, and thus supplies the first longitudinal empirical assessment of these variables’ relationships. Using naturalistic student project groups comprised of 3-5 teammates, the present research tracks the temporal relationships between prestige, dominance and social rank— provided through round-robin teammate-ratings—from the initial formation of collaborative task groups through to the end of a 16-week long academic semester. Results indicate that, whilst dominance and prestige both promoted social rank in unacquainted groups initially and were distinct processes throughout the period examined, only prestige had a positive effect on social rank over time. Further results reveal that the temporal relationship between prestige and social rank was bidirectional, such that acquiring social rank further perpetuates future prestige. Overall, findings present a framework for the longitudinal distinction between prestige and dominance

Dynamic modeling of practice effects across the healthy aging-Alzheimer’s disease continuum

Standardized tests of learning and memory are sensitive to changes associated with both aging and superimposed neurodegenerative diseases. Unfortunately, repeated behavioral test administration can be confounded by practice effects (PE), which may obscure declines in level of abilities and contribute to misdiagnoses. Growing evidence, however, suggests PE over successive longitudinal measurements may differentially predict cognitive status and risk for progressive decline associated with aging, mild cognitive impairment (MCI), and dementia. Thus, when viewed as a reflection of neurocognitive plasticity, PE may reveal residual abilities that can add to our understanding of age- and disease-related changes in learning and memory. The present study sought to evaluate differences in PE and verbal recall in a clinically characterized aging cohort assessed on multiple occasions over 3 years. Participants included 256 older adults recently diagnosed as cognitively unimpaired (CU; n = 126), or with MCI of amnestic (n = 65) or non-amnestic MCI (n = 2085), and multi-domain amnestic dementia of the Alzheimer’s type (DAT; n = 45). We applied a continuous time structural equation modeling (ctsem) approach to verbal recall performance on the Hopkins Verbal Learning Test in order to distinguish PE from individual occasion performance, coupled random changes, age trends, and differing measurement quality. Diagnoses of MCI and dementia were associated with lower recall performance on all trials, reduced PE gain per occasion, and differences in non-linear dynamic parameters. Practice self-feedback is a dynamic measure of the decay or acceleration in PE process changes over longitudinal occasions. As with PE and mean recall, estimated practice self-feedback followed a gradient from positive in CU participants to null in participants with diagnosed MCI and negative for those with dementia diagnoses. Evaluation of sensitivity models showed this pattern of variation in PE was largely unmodified by differences in age, sex, or educational attainment. These results show dynamic modeling of PE from longitudinal performance on standardized learning and memory tests can capture multiple aspects of behavioral changes in MCI and dementia. The present study provides a new perspective for modeling longitudinal change in verbal learning in clinical and cognitive aging research

Tactile-visual links in exogenous spatial attention under different postures: convergent evidence from psychophysics and ERPs

Tactile-visual links in spatial attention were examined by presenting spatially nonpredictive tactile cues to the left or right hand, shortly prior to visual targets in the left or right hemifield. To examine the spatial coordinates of any cross-modal links, different postures were examined. The hands were either uncrossed, or crossed so that the left hand lay in the right visual field and vice versa. Visual judgments were better on the side where the stimulated hand lay, though this effect was somewhat smaller with longer intervals between cue and target, and with crossed hands. Event-related brain potentials (ERPs) showed a similar pattern. Larger amplitude occipital N1 components were obtained for visual events on the same side as the preceding tactile cue, at ipsilateral electrode sites. Negativities in the Nd2 interval at midline and lateral central sites, and in the Nd1 interval at electrode Pz, were also enhanced for the cued side. As in the psychophysical results, ERP cueing effects during the crossed posture were determined by the side of space in which the stimulated hand lay, not by the anatomical side of the initial hemispheric projection for the tactile cue. These results demonstrate that crossmodal links in spatial attention can influence sensory brain responses as early as the N1, and that these links operate in a spatial frame-of-reference that can remap between the modalities across changes in posture

The stellar contribution to the extra-galactic background light and absorption of high-energy gamma-rays

TeV gamma rays from distant astrophysical sources are attenuated due to electron-positron pair creation by interacting with ultraviolet/optical to infrared photons which fill the universe and are collectively known as the extra-galactic background light (EBL). We model the ~0.1-10 eV starlight component of the EBL derived from expressions for the stellar initial mass function, star formation history of the universe, and wavelength-dependent absorption of a large sample of galaxies in the local universe. These models are simultaneously fitted to the EBL data as well as to the data on the stellar luminosity density in our local universe. We find that the models with modified Salpeter A initial mass function together with Cole et al. (2001) or Hopkins and Beacom (2006) star formation history best represent available data. Since no dust emission is included, our calculated EBL models can be interpreted as the lower limits in the ~0.1-1 eV range. We present simple analytic fits to the best-fit EBL model evolving with redshift. We then proceed to calculate gamma-ray opacities, and absorption of ~10-300 GeV gamma-rays coming from different redshifts. We discuss implications of our results for the Fermi Gamma Ray Space Telescope and ground-based Air Cherenkov Telescopes.Comment: 30 pages, 11 figures and 1 table. Substantially revised but the formalism remains unchanged. Accepted in Ap