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The Single Stage AMS radiocarbon facility at the Australian National University has operated for the past 14 years. This paper presents the pretreatment methods used for the major sample types dated and reflects on whether quality assurance protocols can adequately detect altered materials. The majority of fossil samples dated by the facility are from tropical and arid environments where diagenesis of both organic samples and carbonates is often severe. A large proportion of the samples submitted cannot be dated, and screening and quality assurance methods are crucial. Based on analysis of 250 measurements on bone collagen, quality assurance indicators for bone are revised. From May 2021, the laboratory has accepted dates on collagen where yield >0.5%, %C is in the range of 39.7–46.9, and the C:N ratio is between 3.00 and 3.30. [ABSTRACT FROM AUTHOR]

Summary: Eating patterns involving intermittent energy restriction (IER) include 'intermittent fasting' where energy intake is severely restricted for several 'fasting' days per week, with 'refeeding' days (involving greater energy intake than during fasting days) at other times. Intermittent fasting does not improve weight loss compared to continuous energy restriction (CER), where energy intake is restricted every day. We hypothesize that weight loss from IER could be improved if refeeding phases involved restoration of energy balance (i.e. not ongoing energy restriction, as during intermittent fasting). There is some evidence in adults with overweight or obesity showing that maintenance of a lower weight may attenuate (completely or partially) some of the adaptive responses to energy restriction that oppose ongoing weight loss. Other studies show some adaptive responses persist unabated for years after weight loss. Only five randomized controlled trials in adults with overweight or obesity have compared CER with IER interventions that achieved energy balance (or absence of energy restriction) during refeeding phases. Two reported greater weight loss than CER, whereas three reported similar weight loss between interventions. While inconclusive, it is possible that achieving energy balance (i.e. avoiding energy restriction or energy excess) during refeeding phases may be important in realizing the potential of IER. [ABSTRACT FROM AUTHOR]

Torres et al. (2010) published a series of radiocarbon, AAR, ESR and OSL dates from the site of El Sidrón, northern Spain, which is notable for the discovery of the partial remains of 12 Neanderthals. Whilst the non-radiocarbon methods suggested an age beyond 32 600-46 300 years, direct radiocarbon dates on the human fossils were inconsistent, ranging between 10 000 and 50 000 bp. This study uses the ultrafiltration pre-treatment protocol to obtain a date of 48 400 ± 3200 bp (OxA-21 776) on a bone fragment and confirm the antiquity of the Neanderthal assemblage. Moreover, it demonstrates the comparability of the ultrafiltration and ninhydrin bone radiocarbon pre-treatment protocols, and highlights the need for appropriate screening methods where valuable collections with poor biomolecular preservation are sampled for collagen extraction. [ABSTRACT FROM AUTHOR]

If ancient carbon is incorporated into lakes and rivers, it can be transferred along the foodchain where it can cause radiocarbon dates to appear erroneously old. This effect is known as the 14C freshwater reservoir effect (FRE), and causes particular problems when dating human remains. Several studies have attempted to use carbon and/or nitrogen stable isotopes to predict the size of the FRE, with mixed success. We have examined whether the FRE at the Mesolithic-Neolithic burial ground of Minino, northwest Russia, is correlated with these stable isotope systems. To assess the size of the FRE, 9 pairs of human bone and burial goods were dated, such as spears and pendants made of herbivore bone. In addition, further human and faunal bones were analyzed for carbon and nitrogen stable isotopes. Although these stable isotopes suggest that freshwater resources dominated the protein intake of those buried at Minino, no relationship between stable isotopes and the FRE was found. Instead, we found that the FRE was relatively consistent at 490 ± 80 14C yr. With caution, this can be subtracted from burials at Minino to provide a low-resolution chronology for the burial ground. We demonstrate that it is not possible to assume that a relationship exists between stable isotopes and 14C, and each population thought to be affected by a FRE must be examined individually. [ABSTRACT FROM AUTHOR]

Controversy exists as to whether there is less secondary caries at the margins of glass ionomer restorations compared with other materials that do not increase fluoride. This study examined the incidence iof secondary caries for three types of restorative materials in Class V restorations in xerostomic patients. The study group conissted of 45 high carioes-risk adult patients who had undergone head and neck irradiation for the treatment of cancer. All were substantially xerostomic and in need of at least three restorations in the same arch. Every patient received a restoration with each of the test materials, a conventional glass ionomer (GI) a resin modified gloass ionomer(RMGI) and a resin composite (C). Patients were instructed in the daily use of a neutral pH sodium fluouride gel in custom trays. Recall appointments were made at 6, 12, 18 and 24 months, and the restorations were examined for matwerial loss, marginal integrity and recurrent caries at the restoration margin. Fluoride compliance was determined at each recall period and recoprded as the percentage of reccommended use during that interval. Patients were categorized at the end of the study as fluoride non-users if their average compliance was 50% or less. Those with greater than 50% compliance were categorized as fluoride users. In the latter group, no recurrent caries was found in the fluoride non-user group. None of the GI, one RMGI and eight C restorations failed due to recurrent caries. For the fluoride non-user patients, Fishers exact test (p=0.05) showed no statistical difference between GIO and RMGI but statistical differences were found among tthose materials and resin composite at each recall period. Recurrent caries reductions for GI and RMGI relative to C were greater than 80% in xerostomic patients not using topical fluoride supplementation. [ABSTRACT FROM AUTHOR]

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The article discusses various reports published within the issue, including one by Les Metcalfe on the new role of government in managing competitiveness and another by Rob Shogren on the role of public sector in economic development and trade.

In summary, a patient with multiple coronary aneurysms and operative therapy is described and 17 previously reported similar cases are reviewed. The proper type of operation for this condition is as yet unclear, but, nevertheless, the reported cases and our case with operative therapy have done well postoperatively despite a variety of procedures performed. [ABSTRACT FROM AUTHOR]