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The DIMA Network (Developing Innovative Multi-proxy Analyses – in Siberia and the Russian Far East (SRFE)) started from a small nucleus of palaeoenvironmental researchers in the UK and SRFE at a workshop in 2008 and currently includes researchers from over 25 institutions. The mutual interest in creating long-term records of environmental change was rekindled during workshops in Magadan (2018), Tomsk (2018) and Southampton (2019). These events were organised to connect researchers from the UK and SRFE with these aims: (1) provide training in new techniques and methods, (2) facilitate knowledge transfer about local sites and conditions, (3) stimulate large-scale collaborative projects across SRFE and (4) inspire a new generation of palaeoenvironmental researchers. [ABSTRACT FROM AUTHOR]

One major challenge in the study of late-Quaternary extinctions (LQEs) is providing better estimates of past megafauna abundance. To show how megaherbivore population size varied before and after the last extinctions in interior Alaska, we use both a database of radiocarbon-dated bone remains (spanning 25–0 ka) and spores of the obligate dung fungus, Sporormiella, recovered from radiocarbon-dated lake-sediment cores (spanning 17–0 ka). Bone fossils show that the last stage of LQEs in the region occurred at about 13 ka ago, but the number of megaherbivore bones remains high into the Holocene. Sporormiella abundance also remains high into the Holocene and does not decrease with major vegetation changes recorded by arboreal pollen percentages. At two sites, the interpretation of Sporormiella was enhanced by additional dung fungal spore types (e.g., Sordaria). In contrast to many sites where the last stage of LQEs is marked by a sharp decline in Sporormiella abundance, in interior Alaska our results indicate the continuance of megaherbivore abundance, albeit with a major taxonomic turnover (including Mammuthus and Equus extinction) from predominantly grazing to browsing dietary guilds. This new and robust evidence implies that regional LQEs were not systematically associated with crashes of overall megaherbivore abundance. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated which databases and which combinations of databases should be used to identify economic evaluations (EEs) to inform systematic reviews. It also investigated the characteristics of studies not identified in database searches and evaluated the success of MEDLINE search strategies used within typical reviews in retrieving EEs in MEDLINE.Methods: A quasi-gold standard (QGS) set of EEs was collected from reviews of EEs. The number of QGS records found in nine databases was calculated and the most efficient combination of databases was determined. The number and characteristics of QGS records not retrieved from the databases were collected. Reproducible MEDLINE strategies from the reviews were rerun to calculate the sensitivity and precision for each strategy in finding QGS records.Results: The QGS comprised 351 records. Across all databases, 337/351 (96 percent) QGS records were identified. Embase yielded the most records (314; 89 percent). Four databases were needed to retrieve all 337 references: Embase + Health Technology Assessment database + (MEDLINE or PubMed) + Scopus. Four percent (14/351) of records could not be found in any database. Twenty-nine of forty-one (71 percent) reviews reported a reproducible MEDLINE strategy. Ten of twenty-nine (34.5 percent) of the strategies missed at least one QGS record in MEDLINE. Across all twenty-nine MEDLINE searches, 25/143 records were missed (17.5 percent). Mean sensitivity was 89 percent and mean precision was 1.6 percent.Conclusions: Searching beyond key databases for published EEs may be inefficient, providing the search strategies in those key databases are adequately sensitive. Additional search approaches should be used to identify unpublished evidence (grey literature). [ABSTRACT FROM AUTHOR]

In the article, the author discusses the relationship among gender, shame and visibility. Also cited are the traditional characterizations of shame, the feelings of invisibility and shame of oppressed persons compared to that of socially privileged individuals, as well as the reasons why women seems to be more shame-prone than men as cited by Joanne Entwiste.

Holocene tephrostratigraphy in Alaska provides independent chronology and stratigraphic correlation in a region where reworked old (Holocene) organic carbon can significantly distort radiocarbon chronologies. Here, we present new glass chemistry and chronology for Holocene tephras preserved in three Alaskan lakes: one in the eastern interior and two in the southern Brooks Range. Tephra beds in the eastern interior lake-sediment core are correlated with the White River Ash and the Hayes tephra set H (~4200–3700 cal yr BP), and an additional discrete tephra bed is likely from the Aleutian arc/Alaska Peninsula. Cryptotephras (nonvisible tephras) found in the Brooks Range include the informally named “Ruppert tephra” (~2700–2300 cal yr BP) and the Aniakchak caldera-forming event II (CFE II) tephra (~3600 cal yr BP). A third underlying Brooks Range cryptotephra is chemically indistinguishable from the Aniakchak CFE II tephra (4070–3760 cal yr BP) and is likely to be from an earlier eruption of the Aniakchak volcano. [ABSTRACT FROM PUBLISHER]

Objectives: This study was designed to assess the sensitivity of three Ovid MEDLINE search filters developed to identify studies reporting health state utility values (HSUVs), to improve the performance of the best performing filter, and to validate resulting search filters. Methods: Three quasi-gold standard sets (QGS1, QGS2, QGS3) of relevant studies were harvested from reviews of studies reporting HSUVs. The performance of three initial filters was assessed by measuring their relative recall of studies in QGS1. The best performing filter was then developed further using QGS2. This resulted in three final search filters (FSF1, FSF2, and FSF3), which were validated using QGS3. Results: FSF1 (sensitivity maximizing) retrieved 132/139 records (sensitivity: 95 percent) in the QGS3 validation set. FSF1 had a number needed to read (NNR) of 842. FSF2 (balancing sensitivity and precision) retrieved 128/139 records (sensitivity: 92 percent) with a NNR of 502. FSF3 (precision maximizing) retrieved 123/139 records (sensitivity: 88 percent) with a NNR of 383. Conclusions: We have developed and validated a search filter (FSF1) to identify studies reporting HSUVs with high sensitivity (95 percent) and two other search filters (FSF2 and FSF3) with reasonably high sensitivity (92 percent and 88 percent) but greater precision, resulting in a lower NNR. These seem to be the first validated filters available for HSUVs. The availability of filters with a range of sensitivity and precision options enables researchers to choose the filter which is most appropriate to the resources available for their specific research. [ABSTRACT FROM AUTHOR]

A megaslump at Batagaika, in northern Yakutia, exposes a remarkable stratigraphic sequence of permafrost deposits ~50–80 m thick. To determine their potential for answering key questions about Quaternary environmental and climatic change in northeast Siberia, we carried out a reconnaissance study of their cryostratigraphy and paleoecology, supported by four rangefinder 14C ages. The sequence includes two ice complexes separated by a unit of fine sand containing narrow syngenetic ice wedges and multiple paleosols. Overall, the sequence developed as permafrost grew syngenetically through an eolian sand sheet aggrading on a hillslope. Wood remains occur in two forest beds, each associated with a reddened weathering horizon. The lower bed contains high amounts of Larix pollen (>20%), plus small amounts of Picea and Pinus pumila, and is attributed to interglacial conditions. Pollen from the overlying sequence is dominated by herbaceous taxa (~70%–80%) attributed to an open tundra landscape during interstadial climatic conditions. Of three hypothetical age schemes considered, we tentatively attribute much of the Batagaika sequence to Marine Oxygen Isotope Stage (MIS) 3. The upper and lower forest beds may represent a mid–MIS 3 optimum and MIS 5, respectively, although we cannot discount alternative attributions to MIS 5 and 7. [ABSTRACT FROM AUTHOR]

Introduction: Systematic reviews are important for informing decision-making and primary research, but they can be time consuming and costly. With the advent of machine learning, there is an opportunity to accelerate the review process in study screening. We aimed to understand the literature to make decisions about the use of machine learning for screening in our review workflow. Methods: A pragmatic literature review of PubMed to obtain studies evaluating the accuracy of publicly available machine learning screening tools. A single reviewer used 'snowballing' searches to identify studies reporting accuracy data and extracted the sensitivity (ability to correctly identify included studies for a review) and specificity, or workload saved (ability to correctly exclude irrelevant studies). Results: Ten tools (AbstractR, ASReview Lab, Cochrane RCT classifier, Concept encoder, Dpedia, DistillerAI, Rayyan, Research Screener, Robot Analyst, SWIFT-active screener) were evaluated in a total of 16 studies. Fourteen studies were single arm where, although compared with a reference standard (predominantly single reviewer screening), there was no other comparator. Two studies were comparative, where tools were compared with other tools as well as a reference standard. All tools ranked records by probability of inclusion and either (i) applied a cut-point to exclude records or (ii) were used to rank and re-rank records during screening iterations, with screening continuing until most relevant records were obtained. The accuracy of tools varied widely between different studies and review projects. When used in method (ii), at 95 percent to 100 percent sensitivity, tools achieved workload savings of between 7 percent and 99 percent. It was unclear whether evaluations were conducted independent of tool developers. Conclusions: Evaluations suggest the potential for tools to correctly classify studies in screening. However, conclusions are limited since (i) tool accuracy is generally not compared with dual reviewer screening and (ii) the literature lacks comparative studies and, because of between-study heterogeneity, it is not possible to robustly determine the accuracy of tools compared with each other. Independent evaluations are needed. [ABSTRACT FROM AUTHOR]

Aim: The primary objective of this study was to determine whether adults with a chronic illness within a primary care setting who received a rehabilitation intervention in this setting showed greater improvement in health status and had fewer hospital admissions and emergency room visits compared with adults who do not receive the intervention. Background: More than half of Canadians (16 million people) live with chronic illness. Persons with chronic illness in primary care, especially older persons who are most at risk for functional decline, are currently not receiving effective management. Methods: A randomized controlled trial was used. A rehabilitation multi-component intervention was delivered by a physiotherapist (PT) and occupational therapist in a primary care setting and included collaborative goal setting for rehabilitation needs, a six-week chronic disease self-management (SM) workshop, referral to community programs and a web-based education programme. Findings: Three hundred and three patients participated, n = 152 intervention group and n = 151 in the control group. There was a significant difference between the groups for planned hospital days (F = 6.3, P = 0.00) with an adjusted difference 0.60 day per person, and increased satisfaction with rehabilitation services however no difference on health status or emergency room visits. This rehabilitation intervention which had a strong SM component prevented planned hospitalizations that resulted in a conservative estimated cost saving from reduced hospitalizations of $65 000. Future research needs to examine which patient groups with chronic illness show positive responses to rehabilitation and self-management. [ABSTRACT FROM AUTHOR]

Abstract: Burial Lake in northwest Alaska records changes in water level and regional vegetation since ∼39,000calyr BP based on terrestrial macrofossil AMS radiocarbon dates. A sedimentary unconformity is dated between 34,800 and 23,200calyr BP. During all or some of this period there was a hiatus in deposition indicating a major drop in lake level and deflation of lacustrine sediments. MIS 3 vegetation was herb-shrub tundra; more xeric graminoid-herb tundra developed after 23,200calyr BP. The tundra gradually became more mesic after 17,000calyr BP. Expansions of Salix then Betula, at 15,000 and 14,000calyr BP, respectively, are coincident with a major rise in lake level marked by increasing fine-grained sediment and higher organic matter content. Several sites in the region display disrupted sedimentation and probable hiatuses during the last glacial maximum (LGM); together regional data indicate an arid interval prior to and during the LGM and continued low moisture levels until ∼15,000calyr BP. AMS 14C dates from Burial Lake are approximately synchronous with AMS 14C dates reported for the Betula expansion at nearby sites and sites across northern Alaska, but 1000–2000yr younger than bulk-sediment dates. [Copyright &y& Elsevier]