Radiocarbon dates from the Oxford AMS system: archaeometry datelist 35

This is the 35th list of AMS radiocarbon determinations measured at the Oxford Radiocarbon Accelerator Unit (ORAU). Amongst some of the sites included here are the latest series of determinations from the key sites of Abydos, El Mirón, Ban Chiang, Grotte de Pigeons (Taforalt), Alepotrypa and Oberkassel, as well as others dating to the Palaeolithic, Mesolithic and later periods. Comments on the significance of the results are provided by the submitters of the material

The potential and pitfalls of using simple dental metrics to infer the diets of African antelopes (Mammalia: Bovidae)

The use of mesowear to infer diets of extinct species is fast becoming widespread in palaeoecological studies. Nevertheless, traditional mesowear analyses suffer from a specimen number limitation, in that a minimum number of specimens identified to the species level is necessary to make accurate dietary predictions. This is problematic in many fossil African antelope (Mammalia: Bovidae) assemblages, where isolated teeth cannot always be assigned to species. Hereweexplore the possibility of using simple dental metrics to predict diets on the basis of individual teeth as well as gnathic rows using linear discriminant function analyses.We find that browsers are accurately classified at both the individual and species levels, across all models and tooth positions. Mixed feeders and grazers are classified accurately only sometimes, and this is probably a reflection of the more limited sample size of larger bodied species in our study. Body size was a highly significant predictor of the inaccurate classifications obtained in our models, with larger bodied species tending to grazing classifications and smaller bodied species browsing classifications. Nevertheless, the models correctly classify the majority of specimens we examined to their correct trophic group, as determined through stable isotope analyses or as defined through the literature. The methods outlined hold some promise for determining the diets of isolated fossil specimens unassigned to species in a simple manner and, when used in conjunction with other palaeodietary and palaeoecological proxies, may help determine palaeoenvironments more accurately

Old stones’ song—second verse: use-wear analysis of rhyolite and fenetized andesite artifacts from the Oldowan lithic industry of Kanjera South, Kenya

This paper investigates Oldowan hominin behavioral ecology through use-wear analysis of artifacts from Kanjera South, Western Kenya. It extends development of our experimental use-wear reference collection and analysis of use-wear on the well preserved and unweathered Oldowan tools from this site to include rhyolite, a non-local material of similar durability to previously studied quartz and quartzite tools, and fenetized andesite, a local material with considerably less durability. Variability in rhyolite and fenetized andesite texture, inclusions, and matrix required enhancement of previous methods so we combine the use of stereoscopic, metallographic, and scanning electron microscopy in this study. This study allows us to begin exploration of the links between specific artifactual raw materials and the materials they were used to process. Data assembled so far suggest that tools fashioned from non-local and local stone were, with one possible exception, used to process similar materials. Additionally, experiments carried out with replicas of tools made of rhyolite and fenetized andesite confirm interpretation of reduction sequences that tools made of less durable local material had a shorter use-life and were used expediently compared to the more durable non-local quartz, quartzite, and rhyolite. These new data improve our understanding, of the functional needs, behavioral solutions, and cognitive capacities of Oldowan hominins. Finally, these data show how use-wear analysis, combined with lithic raw material and lithic technology, can be a powerful means for evaluating two key points for human evolution: long-term memory, and planning

Climate reconstruction from Barrow Island, Western Australia

Barrow Island ( 20.7°S) is ideally situated to register the first coastal occupations in Australia as well as peoples' responses to major changes in sea level, climate and eventual isolation from critical resources on the mainland. Its location in the arid region between monsoonal and extratropical rainfall belts also imply that Barrow Island may have experienced dramatic changes in precipitation over the period of human occupation. Boodie cave has been the focus of Barrow Island Archeological Project and records a rich record of human occupation. Also present at Boodie cave are significant quantities of water-lain cave carbonates (flowstones, stalactites, and stalagmites). Active (modern) deposition of such carbonates is limited to very small encrustations and consists primarily of stalactites that are less than 5 cm in diameter. This situation indicates that deposition of significant carbonates is indicative of wetter conditions at Barrow Island and dating of these carbonates using the U/Th method provides a record of wet intervals at Barrow Island over the last 120 thousand years. In addition to ages from flowstones, three complete speleothems were collected Ledge Cave for climatic reconstruction using stable isotopes. Ledge cave is large subterranean with high relative humidity (>98%) and abundant, but largely inactive speleothems. The wettest interval in our cave carbonate record predates stratigraphic units with cultural material, but indicates that wet intervals on Barrow Island were broadly coincidental with lake expansions on the Australian mainland. In particular, a very wet interval between 120 and 90 ka is recorded in two of the Ledge Cave speleothems. The Barrow Island speleothem record suggests that displacement of the Intertropical Convergence Zone (ITCZ) and the strength of the Indo-Australian monsoon may have been the most important influence on water balance at Barrow Island. Continued development of these climate archives will offer insights into climate that is directly applicable to the unique human occupation record also preserved at this site

Physicochemical Properties of Grain and Starch from Kanihua (chenopodium Pallidicaule) Compared with Quinoa (chenopodium Quinoa) Originated from Peru

Kanihua and quinoa are closely related Andean grains that are unconventional starch sources. Starch was extracted from two kanihua and three quinoa genotypes and their physicochemical properties (proximate analysis, scanning electron microscopy, distribution and particle size, X-ray diffraction, FTIR, solubility, swelling power, pasting and thermal properties) were investigated. Kanihua and quinoa grains presented spherical shapes and regular sizes (1.05 - 1.30 mm). The starch granules show asymmetric monomodal distribution for all cases. Meanwhile, Sauter diameter values in kanihua were smaller (0.961 µm) than quinoa (1.099 µm). Regarding structure, all samples showed Type A polymorphism and similar FTIR spectra behavior. In addition, amilose content was around 11-14% and 8-12% for varieties of kanihua and quinoa respectively. Starch solubilities were less than 13%, and kanihua starches had less swelling power than quinoa starches. However, the maximum swelling power values were reached around 70 °C. The variety and type of grain influenced pasting properties, with an inverse relationship between the breakdown and setback values for the evaluated starches. Analyzing the thermal properties, gelatinization enthalpy and retrogradation were similar for all starches. Even though the kanihua and quinoa starches present similar structural characteristics, the pasting properties and swelling power were different. The insight into the morphological, thermal, and pasting properties of native Chenopodium starches could be helpful in the preparation and development of new food formulations

The significance of 'the visit' in an English category-B prison: Views from prisoners, prisoners' families and prison staff

A number of claims have been made regarding the importance of prisoners staying in touch with their family through prison visits, firstly from a humanitarian perspective of enabling family members to see each other, but also regarding the impact of maintaining family ties for successful rehabilitation, reintegration into society and reduced re-offending. This growing evidence base has resulted in increased support by the Prison Service for encouraging the family unit to remain intact during a prisoner’s incarceration. Despite its importance however, there has been a distinct lack of research examining the dynamics of families visiting relatives in prison. This paper explores perceptions of the same event – the visit – from the families’, prisoners’ and prison staffs' viewpoints in a category-B local prison in England. Qualitative data was collected with 30 prisoners’ families, 16 prisoners and 14 prison staff, as part of a broader evaluation of the visitors’ centre. The findings suggest that the three parties frame their perspective of visiting very differently. Prisoners’ families often see visits as an emotional minefield fraught with practical difficulties. Prisoners can view the visit as the highlight of their time in prison and often have many complaints about how visits are handled. Finally, prison staff see visits as potential security breaches and a major organisational operation. The paper addresses the current gap in our understanding of the prison visit and has implications for the Prison Service and wider social policy

Excited States of Ladder-type Poly-p-phenylene Oligomers

Ground state properties and excited states of ladder-type paraphenylene oligomers are calculated applying semiempirical methods for up to eleven phenylene rings. The results are in qualitative agreement with experimental data. A new scheme to interpret the excited states is developed which reveals the excitonic nature of the excited states. The electron-hole pair of the S1-state has a mean distance of approximately 4 Angstroem.Comment: 24 pages, 21 figure

Cassava starch biodegradable films: Influence of glycerol and clay nanoparticles content on tensile and barrier properties and glass transition temperature

In this this study, glycerol content and its incorporation method on tensile and barrier properties of biodegradable films (BF) based on cassava starch were analyzed. ANOVA showed that the glycerol incorporation method did not influence the results (P > 0.05), however the glycerol content influenced significantly the tensile and barrier properties of the films (P < 0.05). Films prepared with lower glycerol content presented better tensile and barrier properties than films with higher content. Films were then prepared with addition of clay nanoparticles and their tensile and barrier properties and glass transition temperature were measured. ANOVA indicated that both glycerol and clay nanoparticles influenced significantly the tensile and barrier properties (P < 0.05), diminishing film permeability when clay nanoparticles were present, while the glass transition temperature was not influenced (P > 0.05). (C) 2011 Elsevier Ltd. All rights reserved.FAPESP (The State of Sao Paulo Research Foundation)CAPES (Brazilian Committee for Postgraduate Courses in Higher Education

Synthetic and computational studies on the tricarboxylate core of 6,7-dideoxysqualestatin H5 involving a carbonyl ylide cycloaddition–rearrangement

Reaction of diazodiketoesters 17 and 28 with methyl glyoxylate in the presence of catalytic rhodium(II) acetate generates predominantly the 6,8-dioxabicyclo[3.2.1]octanes 29 and 30, respectively. Acid-catalysed rearrangement of the corresponding alcohol 31 favours, at equilibrium, the 2,8-dioxabicyclo[3.2.1]octane skeleton 33 of the squalestatins–zaragozic acids. Force field calculations on the position of the equilibrium gave misleading results. DFT calculations were correct in suggesting that the energy difference between 31 and 33 should be small, but did not always suggest the right major product. Calculation of the NMR spectra of the similar structures could be used to assign the isomers with a high level of confidence