The RESET project: constructing a European tephra lattice for refined synchronisation of environmental and archaeological events during the last c. 100 ka

This paper introduces the aims and scope of the RESET project (. RESponse of humans to abrupt Environmental Transitions), a programme of research funded by the Natural Environment Research Council (UK) between 2008 and 2013; it also provides the context and rationale for papers included in a special volume of Quaternary Science Reviews that report some of the project's findings. RESET examined the chronological and correlation methods employed to establish causal links between the timing of abrupt environmental transitions (AETs) on the one hand, and of human dispersal and development on the other, with a focus on the Middle and Upper Palaeolithic periods. The period of interest is the Last Glacial cycle and the early Holocene (c. 100-8 ka), during which time a number of pronounced AETs occurred. A long-running topic of debate is the degree to which human history in Europe and the Mediterranean region during the Palaeolithic was shaped by these AETs, but this has proved difficult to assess because of poor dating control. In an attempt to move the science forward, RESET examined the potential that tephra isochrons, and in particular non-visible ash layers (cryptotephras), might offer for synchronising palaeo-records with a greater degree of finesse. New tephrostratigraphical data generated by the project augment previously-established tephra frameworks for the region, and underpin a more evolved tephra 'lattice' that links palaeo-records between Greenland, the European mainland, sub-marine sequences in the Mediterranean and North Africa. The paper also outlines the significance of other contributions to this special volume: collectively, these illustrate how the lattice was constructed, how it links with cognate tephra research in Europe and elsewhere, and how the evidence of tephra isochrons is beginning to challenge long-held views about the impacts of environmental change on humans during the Palaeolithic. © 2015 Elsevier Ltd.RESET was funded through Consortium Grants awarded by the Natural Environment Research Council, UK, to a collaborating team drawn from four institutions: Royal Holloway University of London (grant reference NE/E015905/1), the Natural History Museum, London (NE/E015913/1), Oxford University (NE/E015670/1) and the University of Southampton, including the National Oceanography Centre (NE/01531X/1). The authors also wish to record their deep gratitude to four members of the scientific community who formed a consultative advisory panel during the lifetime of the RESET project: Professor Barbara Wohlfarth (Stockholm University), Professor Jørgen Peder Steffensen (Niels Bohr Institute, Copenhagen), Dr. Martin Street (Romisch-Germanisches Zentralmuseum, Neuwied) and Professor Clive Oppenheimer (Cambridge University). They provided excellent advice at key stages of the work, which we greatly valued. We also thank Jenny Kynaston (Geography Department, Royal Holloway) for construction of several of the figures in this paper, and Debbie Barrett (Elsevier) and Colin Murray Wallace (Editor-in-Chief, QSR) for their considerable assistance in the production of this special volume.Peer Reviewe

Cross‐cultural assessment of HIV‐associated cognitive impairment using the Kaufman assessment battery for children: a systematic review

Introduction: Despite improved efficacy of, and access to, combination antiretroviral therapy (cART), HIV‐associated cognitive impairments remain prevalent in both children and adults. Neuropsychological tests that detect such impairment can help clinicians formulate effective treatment plans. The Kaufman Assessment Battery for Children (KABC), although developed and standardized in the United States, is used frequently in many different countries and cultural contexts to assess paediatric performance across various cognitive domains. This systematic review investigated the cross‐cultural utility of the original KABC, and its 2nd edition (KABC‐II), in detecting HIV‐associated cognitive impairment in children and adolescents.Methods: We entered relevant keywords and MeSH terms into the PubMed, PsycInfo, EBSCOHost, ProQuest, and Scopus databases, with search limits set from 1983–2017. Two independent reviewers evaluated the retrieved abstracts and manuscripts. Studies eligible for inclusion in the review were those that (a) used the KABC/KABC‐II to assess cognitive function in children/adolescents aged 2–18 years, (b) featured a definition of cognitive impairment (e.g. >2 SD below the mean) or compared the performance of HIV‐infected and uninfected control groups, and (c) used a sample excluded from population on which the instruments were normed.Results and discussion: We identified nine studies (eight conducted in African countries, and one in the United Kingdom) to comprise the review’s sample. All studies detected cognitive impairment in HIV‐infected children, including those who were cART‐naïve or who were cART treated and clinically stable. KABC/KABC‐II subtests assessing simultaneous processing appeared most sensitive. Evaluation of the methodological quality of the selected studies by two independent reviews suggested that shortcomings included reporting and selection biases.Conclusions: This systematic review provides evidence for the cross‐cultural utility of the KABC/KABC‐II, particularly the simultaneous processing subtests, in detecting cognitive impairment in HIV‐infected children (including those who are clinically stable). Although the current results suggest there is justification for using the KABC/KABC‐II primarily in East Africa, further investigation is required to explore the instrument’s utility in other HIV‐prevalent regions of the globe.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138351/1/jia21412.pd

Testing the application of post IR-IRSL dating to fine grain waterlain sediments

The polymineral fine grain fraction of a set of ten known age samples were used to test the suitability of elevated temperature post-IR infrared stimulated luminescence (pIRIR) to date waterlain sediments in Switzerland. Equivalent Dose (De) values were obtained using elevated temperatures of 225 °C (pIRIR225) and 290 °C (pIRIR290) and IRSL50/225 (preceding measurement of pIRIR225), and these displayed a systematic increase with increasing stimulation temperature, which brought those derived from the pIRIR protocols into saturation for the older half of the samples (&gt;100 ka). Significant residuals were recorded for the pIRIR signals, and these were found to further increase following attenuation of the bleaching source confirming that these signals are harder to bleach than the IRSL measured at 50 °C. Fading tests recorded g-values of between 1 and 4%, and displayed no obvious decrease with increasing stimulation temperature. For the younger half of the samples, fading corrected ages for all protocols resulted in overestimation compared to robust independent dating for all samples, and draw into question the relationship of fading measured in a laboratory generated signal to that which is naturally generated. Uncorrected IRSL50/225 ages for all samples were in good agreement with independent dating, but still displayed a general overestimation using pIRIR signals. These overestimations may largely be due to the significant residual doses resulting from the harder to bleach nature of the elevated temperature signal, and present a considerable problem when dating waterlain sediments. A considerable challenge when using the pIRIR signal is to be able to separate the effects of both residual doses and fading and confirm that one is not masking the other. Despite this, the pIRIR protocols were successful at one site, although they offered no benefit compared to dating with more conventional luminescence signals. A comparison of De values derived from a standard IRSL signal to that from IRSL50/225, suggest that the latter overestimates by ∼10% due to a decrease in sensitivity of the sample prior to measurement of the test dose.</p

A ~180,000 years sedimentation history of a perialpine overdeepened glacial trough (Wehntal, N-Switzerland)

A 30 m-deep drill core from a glacially overdeepened trough in Northern Switzerland recovered a ~180 ka old sedimentary succession that provides new insights into the timing and nature of erosion–sedimentation processes in the Swiss lowlands. The luminescence-dated stratigraphic succession starts at the bottom of the core with laminated carbonate-rich lake sediments reflecting deposition in a proglacial lake between ~180 and 130 ka ago (Marine Isotope Stage MIS 6). Anomalies in geotechnical properties and the occurrence of deformation structures suggest temporary ice contact around 140 ka. Up-core, organic content increases in the lake deposits indicating a warming of climate. These sediments are overlain by a peat deposit characterised by pollen assemblages typical of the late Eemian (MIS 5e). An abrupt transition following this interglacial encompasses a likely hiatus and probably marks a sudden lowering of the water level. The peat unit is overlain by deposits of a cold unproductive lake dated to late MIS 5 and MIS 4, which do not show any direct influence from glaciers. An upper peat unit, the so-called «Mammoth peat», previously encountered in construction pits, interrupts this cold lacustrine phase and marks more temperate climatic conditions between 60 and 45 ka (MIS 3). In the upper part of the core, a succession of fluvial and alluvial deposits documents the Late Glacial and Holocene sedimentation in the basin. The sedimentary succession at Wehntal confirms that the glaciation during MIS 6 did not apparently cause the overdeepening of the valley, as the lacustrine basin fill covering most of MIS 6 is still preserved. Consequently, erosion of the basin is most likely linked to an older glaciation. This study shows that new dating techniques combined with palaeoenvironmental interpretations of sediments from such overdeepened troughs provide valuable insights into the past glacial history