Clovis Excavations at Topper 2005-2007: Examining Site Formation Processes at an Upland Paleoindian Site along the Middle Savannah River

With this inaugural issue of the Occasional Papers series of the Southeastern Paleoamerican Survey, we are pleased to offer this monograph by D. Shane Miller which was based on his masters thesis research at the Topper site. His excavations, conducted over 2006-2007, resulted in a 64m square block, the largest contiguous unit yet excavated at Topper. Situated in a previously plowed firebreak on the southern hillside exhibiting partial erosion, it was decided to take advantage of this situation and recover the basal Clovis remains in the undisturbed portion of the profile. This strategy worked well and allowed Miller to fairly quickly access a large, relatively well preserved portion of the Clovis deposit as found in the lower firebreak. Miller presents the first thorough analysis of the Clovis occupation of what has been called the Hillside at Topper, reconstructing the geoarchaeological matrix so necessary for contextualizing these important 13,000 year old artifacts. In the course of his study, he does yeoman service by systematically analyzing the assemblage and stratigraphy by considering a variety of relevant agencies that might have formed or even deformed the original deposit. He provides a compelling reconstruction of the natural and cultural formation processes and concludes that the Clovis deposit as it is found on the hill slope is reasonably intact and interpretable and well suited for archaeological inferences.https://scholarcommons.sc.edu/archanth_occasional_paleoam_papers/1000/thumbnail.jp

Landowners\u27 Perceptions of Conservation Easements: Implications for Effective Persuasive Communication

Conservation easements (CEs) are one of the most popular voluntary, legally binding programs that allow individual landowners to use their property to protect the environment. There is a definite need for educational and persuasive messaging targeted towards landowners regarding adopting conservation easements. Based on previous studies, and confirmed by this study, communication efforts that are led by conservation experts who are also community members are most likely to be well received by landowners in a region. There is currently little to no existing region-specific literature specifically related to the attitudes and behaviors landowners possess towards conservation easements. Additionally, more literature is needed regarding landowners’ communications preferences for learning about CEs; the existing literature focuses broadly on environmental communication. This study aimed to fill a gap in literature by conducting a quantitative survey and qualitative phone interview with landowners in Northwest Arkansas and Northeast Oklahoma. Participants were asked to identify their awareness level knowledge about conservation easements, as well as rank incentivizing and disincentivizing factors that would influence their decision to adopt conservation easements. Researchers identified that there is a strong need for regional easement organizations to increase their awareness-level educational communications efforts. In addition, participants noted a strong desire for more personalized and in-person communications methods to be used by easement organizations

Age-Specific Nesting Performance by Northern Bobwhites

Greater reproductive productivity of adult versus juvenile northern bobwhites (Colinus virginianus) has been hypothesized as a factor for rapid population growth. Research on bobwhites in the western portions of the species’ range has not supported this hypothesis; however, no effort has been made to investigate age-specific reproduction on population dynamics in the southeast. We measured age- specific reproductive parameters between adult and juvenile bobwhites during 2000–2010. We radio-marked 1,069 females of which 308 were adults and 761 were juveniles. Nests per hens for adults (0.78 nests/hen) was slightly greater than that for juveniles (0.65 nests/hen) (P 1⁄4 0.09). Adult productivity was 1.7 times greater than for juveniles in 4 of 10 years which corresponded to years of population growth. No differences were found in initial clutch sizes or nesting success. Adult hens began incubation earlier than juveniles in all but 1 year suggesting increased nesting may be due to early recrudescence in adults. The magnitude of age-specific reproductive differences in short-lived species like bobwhites is not as great as long-lived species, but has implications for understanding bobwhite population dynamics and harvest

Foraging Behavior of Northern Bobwhites in Relation to Resource Availability

Distribution of food resources may influence northern bobwhite (Colinus virginianus) foraging decisions and demographic rates. We tested whether covey movements were sensitive to food availability by spreading sorghum (Sorghum bicolor) every 15 days at 3 rates; high rate (174 L/ha/yr), low rate (44 L/ha/yr), and no feed on 3 sections (~240 ha each) of Tall Timbers Research Station, 2009–2010. We measured sorghum availability spread along a 17 km feeding trail every 5 days. We determined seasonal (1 Nov - 15 Mar) home ranges of radio-tagged coveys (n = 89) and daily movement rates and home ranges of a subset of coveys located every 30 mins, sunrise to sunset (1 Feb - 15 Mar). Diet was determined from harvested bobwhites. Mean sorghum availability (seeds/0.5m2) on the feed trail declined from 50 seeds at day 1 to 12 seeds at day 15, and 11 seeds at day 1 to 0 seeds at day 10, for high and low rates, respectively. Seasonal home ranges did not differ among treatments; however, daily home ranges were smaller for coveys on the high rate areas, as was dispersion of locations within home ranges. Distances to the feed trail from covey and random locations were similar. There was no difference in distance traveled (25.20 m; SE = 0.65) between consecutive covey locations among treatments. Proportion of sorghum in the diet declined precipitously when \u3c15 seeds/0.5m2. We estimated an empirical giving up density of 10–14 seeds/0.5m2, ~1.6 kcals/0.5m2. Food availability, even at high levels, marginally affected covey space use and movement rates during late winter. Other factors affecting bobwhites, such as predator avoidance, or thermal regulation, may have a more significant effect on bobwhite covey daily movements and space use

Laboratory Testing of a Lyot Coronagraph Equipped with an Eighth-Order Notch Filter Image Mask

We have built a series of notch filter image masks that make the Lyot coronagraph less susceptible to low-spatial-frequency optical aberrations. In this paper, we present experimental results of their performance in the lab using monochromatic light. Our tests show that these ``eighth-order'' masks are resistant to tilt and focus alignment errors, and can generate contrast levels of 2 x 10^-6 at 3 lambda/D and 6 x 10^-7 at 10 lambda/D without the use of corrective optics such as deformable mirrors. This work supports recent theoretical studies suggesting that eighth-order masks can provide the Terrestrial Planet Finder Coronagraph with a large search area, high off-axis throughput, and a practical requisite pointing accuracy.Comment: Accepted to ApJ. 16 pages, 7 figures, Contact [email protected] for high resolution image

Technical and economic feasibility of centralized facilities for solar hydrogen production via photocatalysis and photoelectrochemistry

Photoelectrochemical water splitting is a promising route for the renewable production of hydrogen fuel. This work presents the results of a technical and economic feasibility analysis conducted for four hypothetical, centralized, large-scale hydrogen production plants based on this technology. The four reactor types considered were a single bed particle suspension system, a dual bed particle suspension system, a fixed panel array, and a tracking concentrator array. The current performance of semiconductor absorbers and electrocatalysts were considered to compute reasonable solar-to-hydrogen conversion efficiencies for each of the four systems. The U.S. Department of Energy H2A model was employed to calculate the levelized cost of hydrogen output at the plant gate at 300 psi for a 10 tonne per day production scale. All capital expenditures and operating costs for the reactors and auxiliaries (compressors, control systems, etc.) were considered. The final cost varied from $1.60–$10.40 per kg H2 with the particle bed systems having lower costs than the panel-based systems. However, safety concerns due to the cogeneration of O_2 and H_2 in a single bed system and long molecular transport lengths in the dual bed system lead to greater uncertainty in their operation. A sensitivity analysis revealed that improvement in the solar-to-hydrogen efficiency of the panel-based systems could substantially drive down their costs. A key finding is that the production costs are consistent with the Department of Energy's targeted threshold cost of $2.00–$4.00 per kg H_2 for dispensed hydrogen, demonstrating that photoelectrochemical water splitting could be a viable route for hydrogen production in the future if material performance targets can be met

Antecedents and consequences of effectuation and causation in the international new venture creation process

The selection of the entry mode in an international market is of key importance for the venture. A process-based perspective on entry mode selection can add to the International Business and International Entrepreneurship literature. Framing the international market entry as an entrepreneurial process, this paper analyzes the antecedents and consequences of causation and effectuation in the entry mode selection. For the analysis, regression-based techniques were used on a sample of 65 gazelles. The results indicate that experienced entrepreneurs tend to apply effectuation rather than causation, while uncertainty does not have a systematic influence. Entrepreneurs using causation-based international new venture creation processes tend to engage in export-type entry modes, while effectuation-based international new venture creation processes do not predetermine the entry mod

Paying Refugees to Leave

States are increasingly paying refugees to repatriate, hoping to decrease the number of refugees residing within their borders. Drawing on in-depth interviews from East Africa and data from Israeli Labour Statistics, I provide a description of such payment schemes and consider whether they are morally permissible. In doing so, I address two types of cases. In the first type of case, governments pay refugees to repatriate to high-risk countries, never coercing them into returning. I argue that such payments are permissible if refugees’ choices are voluntary and if states allow refugees to return to the host country in the event of an emergency. I then describe cases where states detain refugees, and non-governmental organisations provide their own payments to refugees wishing to repatriate. In such cases, non-governmental organisations are only permitted to provide payments if the funds are sufficient to ensure post-return safety and if providing payments does not reinforce the government’s detention policy

Substructures in WINGS clusters

We search for and characterize substructures in the projected distribution of galaxies observed in the wide field CCD images of the 77 nearby clusters of the WIde-field Nearby Galaxy-cluster Survey (WINGS). This sample is complete in X-ray flux in the redshift range 0.04<z<0.07. We search for substructures in WINGS clusters with DEDICA, an adaptive-kernel procedure. We test the procedure on Monte-Carlo simulations of the observed frames and determine the reliability for the detected structures. DEDICA identifies at least one reliable structure in the field of 55 clusters. 40 of these clusters have a total of 69 substructures at the same redshift of the cluster (redshift estimates of substructures are from color-magnitude diagrams). The fraction of clusters with subclusters (73%) is higher than in most studies. The presence of subclusters affects the relative luminosities of the brightest cluster galaxies (BCGs). Down to L ~ 10^11.2 L_Sun, our observed differential distribution of subcluster luminosities is consistent with the theoretical prediction of the differential mass function of substructures in cosmological simulations.Comment: A&A accepted - figure 6 is available from http://adlibitum.oats.inaf.it/ramella/WINGSfig