The Prehistoric Sites at Choke Canyon Reservoir, Southern Texas: Results of Phase II Archaeological Investigations

Reported in this volume are the results of archaeological investigations at 72 prehistoric sites located in the basin of Choke Canyon Reservoir on the Frio River in Live Oak and McMullen Counties, southern Texas. The sites investigated in this study will be affected in one way or another by a lake formed after construction of Choke Canyon Dam, a project of the United States Bureau of Reclamation CUSBR). The research was sponsored by the USBR as the second and final phase of a two-stage program of archaeological investigations designed to mitigate damage or destruction of cultural resources resulting from dam construction and subsequent long-term inundation of a large area of the Frio River valley. Methods used to study Choke Canyon\u27s prehistoric sites during the Phase II investigation were various types of subsurface excavations, documentation of surface features and characteristics, and collection of artifacts from site surfaces. The people who inhabited the Choke Canyon region in prehistoric times, representing an approximate span of 10,000 years, existed as mobile hunter/gatherer bands. They subsisted by tapping virtually every conceivable source of edible natural food. A full spectrum of animals, from lowly field mice and lizards up to bison and deer, was exploited by various techniques of hunting, trapping, and catching. Large land snails and mussels were sources of meat food that Choke Canyon\u27s prehistoric people could easily gather. Gar, drum, and turtles were taken from local creeks, sloughs, and the river, perhaps using spears, nets, or weirs. Analysis of vertebrate faunal remains, results of which are presented herein, rather conclusively demonstrates that Late Prehistoric people exploited big game species more commonly than did their Archaic period predecessors. Floral products must also have comprised a substantial portion of the foods consumed by Choke Canyon\u27s prehistoric inhabitants. Direct evidence of plant food utilization is nonexistent on the sites. However, the very common occurrence of sandstone manes and metates implies heavy reliance on seeds, nuts, or beans. Also, the tremendous amount of burned rock that accumulated in Archaic components at many sites, often found as very carefully constructed hearth features, suggests that baking or roasting activities were extremely common. Roots, tubers, stalks, and other edible plant parts may have been what was being prepared in these facilities. Diagnostic artifacts recovered from prehistoric sites at Choke Canyon during the various phases of archaeological investigation clearly indicate that the general vicinity witnessed aboriginal activity from Paleo-Indian times up through the early Historic period. Evidence of Paleo-Indian people is limited to surface finds along the valley margin and on high, ancient terrace formations down in the river valley. No in situ subsurface Paleo-Indian components have yet been isolated at Choke Canyon. Where previously the earliest subsurface component known at Choke Canyon dated to the Middle Archaic period (ca. 3400 B.C. to 2400 B.C.), the Phase II excavations led to discovery of an Early Archaic component dating to the period from 5000 B.C. xi to 4000 B.C. While recognizable Paleo-Indian, Early Archaic, and Middle Archaic components are relatively scarce, the Late Archaic and Late Prehistoric periods are amply represented in the prehistoric sites at Choke Canyon. Phase II investigations also produced the first clear indication of an aboriginal component containing evidence of contact with Anglo-Europeans in early historic times. The bulk of cultural, paleobotanical, and vertebrate faunal data representing the prehistory of Choke Canyon indicates that floral and faunal communities and the general climatic regime remained essentially unchanged from at least 4000 B.C. up to the period in historic times when certain livestock and land management practices led to a drastic expansion of brush communities and severe erosion of formerly stable land surfaces

Effect of boron concentration on recombination at the p-Si–Al2O3 interface

We examine the surface passivation properties of Al₂O₃ deposited on boron-doped planar crystalline silicon surfaces as a function of the boron concentration. Both uniformly doped and diffused surfaces are studied, with surface boron concentrations ranging from 9.2 × 10¹⁵ to 5.2 × 10¹⁹ cm⁻³. Atmospheric pressure chemical vapor deposition and thermal atomic layer deposition are used to deposit the Al₂O₃ films. The surface recombination rate of each sample is determined from photoconductance measurements together with the measured dopant profiles via numerical simulation, using the latest physical models. These values are compared with calculations based on the interface properties determined from capacitance–voltage and conductance measurements. It is found that the fundamental surface recombination velocity of electrons, Sn 0 , which describes the chemical passivation of the interface, is independent of the surface boron concentration Ns for Ns  ≤ 3 × 10¹⁹ cm⁻³, and in excellent agreement with values calculated from the interface state density Dit and capture coefficients cn and cp measured on undiffused boron-doped surfaces. We conclude that the physical properties of the Si– Al₂O₃ interface are independent of the boron dopant concentration over this range

Are existing soils data meeting the needs of stakeholders in Europe? An analysis of practical use from policy to field

Soils form a major component of the natural system and their functions underpin many key ecosystem goods and services. The fundamental importance of soils in the environment means that many different organisations and stakeholders make extensive use of soils data and information in their everyday working practices. For many reasons, stakeholders are not always aware that they are reliant upon soil data and information to support their activities. Various reviews of stakeholder needs and how soil information could be improved have been carried out in recent years. However, to date, there has been little consideration of user needs from a non-expert perspective. The aim of this study was to explore the use of explicit and hidden soil information in different organisations across Europe and gain a better understanding of improvements needed in soil data and information to assist in practical use by non-expert stakeholders. An on-line questionnaire was used to investigate different uses of soils data and information with 310 responses obtained from 77 organisations across Europe. Results illustrate the widespread use of soil data and information across diverse organisations within Europe, particularly spatial products and soil functional assessments and tools. A wide range of improvements were expressed with a prevalence for finer scale resolution, trends over time, future scenarios, improved accuracy, non-technical supporting information and better capacity to use GIS. An underlying message is that existing legacy soils data need to be supplemented by new up-to-date data to meet stakeholder needs and information gaps

Epidemiological consequences of household-based antiviral prophylaxis for pandemic influenza

Antiviral treatment offers a fast acting alternative to vaccination; as such it is viewed as a first-line of defence against pandemic influenza in protecting families and households once infection has been detected. In clinical trials, antiviral treatments have been shown to be efficacious in preventing infection, limiting disease and reducing transmission, yet their impact at containing the 2009 influenza A(H1N1)pdm outbreak was limited. To understand this seeming discrepancy, we develop a general and computationally efficient model for studying household-based interventions. This allows us to account for uncertainty in quantities relevant to the 2009 pandemic in a principled way, accounting for the heterogeneity and variability in each epidemiological process modelled. We find that the population-level effects of delayed antiviral treatment and prophylaxis mean that their limited overall impact is quantitatively consistent (at current levels of precision) with their reported clinical efficacy under ideal conditions. Hence, effective control of pandemic influenza with antivirals is critically dependent on early detection and delivery ideally within 24 h.Andrew J. Black, Thomas House, M. J. Keeling and J. V. Ros

Lexical evolution rates by automated stability measure

Phylogenetic trees can be reconstructed from the matrix which contains the distances between all pairs of languages in a family. Recently, we proposed a new method which uses normalized Levenshtein distances among words with same meaning and averages on all the items of a given list. Decisions about the number of items in the input lists for language comparison have been debated since the beginning of glottochronology. The point is that words associated to some of the meanings have a rapid lexical evolution. Therefore, a large vocabulary comparison is only apparently more accurate then a smaller one since many of the words do not carry any useful information. In principle, one should find the optimal length of the input lists studying the stability of the different items. In this paper we tackle the problem with an automated methodology only based on our normalized Levenshtein distance. With this approach, the program of an automated reconstruction of languages relationships is completed

An assessment of ADAMs in bone cells: absence of TACE activity prevents osteoclast recruitment and the formation of the marrow cavity in developing long bones

AbstractADAMs (A Disintegrin And Metalloprotease domain) are metalloprotease–disintegrin proteins that have been implicated in cell adhesion, protein ectodomain shedding, matrix protein degradation and cell fusion. Since such events are critical for bone resorption and osteoclast recruitment, we investigated whether they require ADAMs. We report here which ADAMs we have identified in bone cells, as well as our analysis of the generation, migration and resorptive activity of osteoclasts in developing metatarsals of mouse embryos lacking catalytically active ADAM 17 [TNFα converting enzyme (TACE)]. The absence of TACE activity still allowed the generation of cells showing an osteoclastic phenotype, but prevented their migration into the core of the diaphysis and the subsequent formation of marrow cavity. This suggests a role of TACE in the recruitment of osteoclasts to future resorption sites

The UK risk assessment scheme for all non-native species

1. A pest risk assessment scheme, adapted from the EPPO (European and Mediterranean Plant Protection Organisation) scheme, was developed to assess the risks posed to UK species, habitats and ecosystems by non-native taxa. 2. The scheme provides a structured framework for evaluating the potential for non-native organisms, whether intentional or unintentional introductions, to enter, establish, spread and cause significant impacts in all or part of the UK. Specialist modules permit the relative importance of entry pathways, the vulnerability of receptors and the consequences of policies to be assessed and appropriate risk management options to be selected. Spreadsheets for summarising the level of risk and uncertainty, invasive attributes and economic impact were created. In addition, new methods for quantifying economic impact and summarising risk and uncertainty were explored. 3. Although designed for the UK, the scheme can readily be applied elsewhere

Costs of streamlined HIV care delivery in rural Ugandan and Kenyan clinics in the SEARCH Studys.

OBJECTIVES/DESIGN:As antiretroviral therapy (ART) rapidly expands in sub-Saharan Africa using new efficient care models, data on costs of these approaches are lacking. We examined costs of a streamlined HIV care delivery model within a large HIV test-and-treat study in Uganda and Kenya. METHODS:We calculated observed per-person-per-year (ppy) costs of streamlined care in 17 health facilities in SEARCH Study intervention communities (NCT: 01864603) via micro-costing techniques, time-and-motion studies, staff interviews, and administrative records. Cost categories included salaries, ART, viral load testing, recurring goods/services, and fixed capital/facility costs. We then modeled costs under three increasingly efficient scale-up scenarios: lowest-cost ART, centralized viral load testing, and governmental healthcare worker salaries. We assessed the relationship between community-specific ART delivery costs, retention in care, and viral suppression. RESULTS:Estimated streamlined HIV care delivery costs were $291/ppy. ART ($117/ppy for TDF/3TC/EFV [40%]) and viral load testing ($110/ppy for 2 tests/year [39$51/ppy), recurring costs ($5/ppy), and fixed costs ($7/ppy). Optimized ART scale-up with lowest-cost ART ($100/ppy), annual viral load testing ($24/ppy), and governmental healthcare salaries ($27/ppy), lowered streamlined care cost to$163/ppy. We found clinic-to-clinic heterogeneity in retention and viral suppression levels versus streamlined care delivery costs, but no correlation between cost and either retention or viral suppression. CONCLUSIONS:In the SEARCH Study, streamlined HIV care delivery costs were similar to or lower than prior estimates despite including viral load testing; further optimizations could substantially reduce costs further. These data can inform global strategies for financing ART expansion to achieve UNAIDS 90-90-90 targets