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Librarians at the University of Florida Health Science Center Libraries have begun to intentionally incorporate diversity, equity, and inclusion (DEI) principles into teaching during design, implementation, and evaluation. This article uses four case studies to provide an overview of the librarians' approaches to inclusive teaching (1) an annual workshop for Physical Therapy students on the intersection between DEI, health literacy, and patient education; (2) a librarian‐taught one‐credit course for public health students, which was revised to create a more inviting syllabus and integrate elements of universal design; (3) an annual project for first year medical students highlighting health disparities and community resources; and (4) piloting the application of critical librarianship principles in library standalone sessions on database searching and reference management. Suggestions are provided for other librarians who are interested in developing a culture of inclusive teaching in their own libraries. [ABSTRACT FROM AUTHOR]

Here, we investigate Mid‐ to Late‐Holocene vegetation changes in low‐lying coastal areas in Tonga and how changing sea levels and recurrent volcanic eruptions have influenced vegetation dynamics on four islands of the Tongan archipelago (South Pacific). To investigate past vegetation and environmental change at Ngofe Marsh ('Uta Vava'u), we examined palynomorphs (pollen and spores), charcoal (fire), and sediment characteristics (volcanic activity) from a 6.7‐m‐long sediment core. Radiocarbon dating indicated the sediments were deposited over the last 7700 years. We integrated the Ngofe Marsh data with similar previously published data from Avai'o'vuna Swamp on Pangaimotu Island, Lotofoa Swamp on Foa Island, and Finemui Swamp on Ha'afeva Island. Plant taxa were categorized as littoral, mangrove, rainforest, successional/ disturbance, and wetland groups, and linear models were used to examine relationships between vegetation, relative sea level change, and volcanic eruptions (tephra). We found that relative sea level change has impacted vegetation on three of the four islands investigated. Volcanic eruptions were not identified as a driver of vegetation change. Rainforest decline does not appear to be driven by sea level changes or volcanic eruptions. From all sites analyzed, vegetation at Finemui Swamp was most sensitive to changes in relative sea level. While vegetation on low‐lying Pacific islands is sensitive to changing sea levels, island characteristics, such as area and elevation, are also likely to be important factors that mediate specific island responses to drivers of change. [ABSTRACT FROM AUTHOR]

Human‐mediated changes in island vegetation are, among others, largely caused by the introduction and establishment of non‐native species. However, data on past changes in non‐native plant species abundance that predate historical documentation and censuses are scarce. Islands are among the few places where we can track human arrival in natural systems allowing us to reveal changes in vegetation dynamics with the arrival of non‐native species. We matched fossil pollen data with botanical status information (native, non‐native), and quantified the timing, trajectories and magnitude of non‐native plant vegetational change on 29 islands over the past 5000 years. We recorded a proportional increase in pollen of non‐native plant taxa within the last 1000 years. Individual island trajectories are context‐dependent and linked to island settlement histories. Our data show that non‐native plant introductions have a longer and more dynamic history than is generally recognized, with critical implications for biodiversity baselines and invasion biology. [ABSTRACT FROM AUTHOR]

A submillennial‐resolution record of lake water oxygen isotope composition (δ18O) from chironomid head capsules is presented from Burial Lake, northwest Alaska. The record spans the Last Glacial Maximum (LGM; ~20–16k cal a bp) to the present and shows a series of large lake δ18O shifts (~5‰). Relatively low δ18O values occurred during a period covering the LGM, when the lake was a shallow, closed‐basin pond. Higher values characterize deglaciation (~16–11.5k cal a bp) when the lake was still closed but lake levels were higher. A rapid decline between ~11 and 10.5k cal a bp indicates that lake levels rose to overflowing. Lake δ18O values are interpreted to reflect the combined effects of changes in lake hydrology, growing season temperature and meteoric source water as well as large‐scale environmental changes impacting this site, including opening of the Bering Strait and shifts in atmospheric circulation patterns related to ice‐sheet dynamics. The results indicate significant shifts in precipitation minus evaporation across the late Pleistocene to early Holocene transition, which are consistent with temporal patterns of vegetation change and paludification. This study provides new perspectives on the paleohydrology of eastern Beringia concomitant with human migration and major turnover in megafaunal assemblages. [ABSTRACT FROM AUTHOR]

A detailed, well‐dated record of pollen and sedimentary ancient DNA (sedaDNA) for the period 15 000–9500 cal a bp describes changes at Lake Bolshoye Shchuchye in the Polar Ural Mountains, located far east of the classical Lateglacial sites in western Europe. Arctic tundra rapidly changed to lusher vegetation, possibly including both dwarf (Betula nana) and tree birch (B. pubescens), dated in our record to take place 14 565 cal a bp, coincident with the onset of the Bølling in western Europe; this was paralleled by increased summer temperatures. A striking feature is an early decline in Betula pollen and sedaDNA reads 300 years before the onset of the Younger Dryas (YD) in western Europe. Given the solid site chronology, this could indicate that the YD cooling started in Siberia and propagated westwards, or that the vegetation reacted to the inter‐Allerød cooling at 13 100 cal a bp and did not recover during the late Allerød. During the YD, increases in steppe taxa such as Artemisia and Chenopodiaceae suggest drier conditions. At the onset of the Holocene, the vegetation around the lake reacted fast to the warmer conditions, as seen in the increase of arboreal taxa, especially Betula, and a decrease in herbs such as Artemisia and Cyperaceae. [ABSTRACT FROM AUTHOR]

Aim: Palaeoecological data provide an essential long‐term perspective of ecological change and its drivers in oceanic islands. However, analysing the effects of multi‐scalar and potentially co‐occurring disturbances is particularly challenging in dry islands. Here, we aim to identify the ecological consequences of the integrated impacts of a regional drying trend, volcanic eruptions and human mass migrations in a spatially constrained environment—a small, dry oceanic island in Macaronesia. Location: Brava Island, Republic of Cabo Verde. Taxa: Terrestrial vegetation and fungi. Methods: We use palaeoecological analyses applied to a caldera soil profile that dates back to 9700 cal yr BP (calibrated years before the present). Analyses include pollen (vegetation history), non‐pollen palynomorphs (changes in fern and fungal communities), grain‐size distribution, loss‐on‐ignition and geochemistry (sedimentology and erosion regimes), microscopic tephra shards (volcanic ash deposition) and charcoal (fire regime). Results: A regional drying trend after c. 4000 cal yr BP caused increased erosion but had limited immediate impacts on highland grassland vegetation. The expansion of fern‐rich woody scrubland was contemporaneous with significant deposition of volcanic ash and erosion between 1800 and 650 cal yr BP. About 300 cal yr BP, exogenous plants expanded, grazing and fires increased, and there was a decrease of native vegetation cover. Main conclusions: Throughout the Holocene, highland vegetation in Brava was characterized by the presence of open landscapes dominated by herbaceous species (e.g. Poaceae, Forsskaolea), with some presence of woody native taxa (e.g. Ficus, Dodonaea). A regional drying trend was a driver of erosion since the Mid Holocene but did not have an immediate influence on highland vegetation. Tephra deposition is a possible driver of vegetation change. Inter‐island mass migration after volcanic events in Fogo Island c. 1680 CE potentially triggered land use change and intensification, causing a reduction of native vegetation in Brava. [ABSTRACT FROM AUTHOR]

As concern about the effects of climate change on northern regions increases, an important goal of palaeoenvironmental science is placing events that appear to be unprecedented - such as the severe boreal forest fires of recent years (Witze 2020) - into a long-term context. 19 Razjigaeva, N., Ganzey, L., Grebennikova, T., Mokhova, L., Kopoteva, T., Kudryavtseva, E., Belyanin, P., Panichev, A., Arslanov, K., Maksimov, F., Petrov, A., Sudin, V., Klimin, M. & Kornyushenko, T. 2021: Holocene mountain landscape development and monsoon variation in the southernmost Russian Far East. 3 Blyakharchuk, T. A. 2012: New Palaeopollen Data of Vegetation and Climate Dynamics in West Siberia and Adjacent Areas in the Holocene. (2021, this issue) present a high-elevation lacustrine record from the Eastern Sayan Mountains that records the Younger Dryas interval and Holocene mountain vegetation responses to changes in moisture, driven by monsoon dynamics. [Extracted from the article]

Background: Information specialists frequently translate search filters from one interface to another. Publications advise that translation can be complex and should be undertaken carefully. Objectives: To investigate the issues arising when translating the Cochrane Embase RCT search filter from one interface (Ovid) to another (Embase.com). Methods: We drafted a translation of the Cochrane Ovid RCT filter to run in Embase.com. We compared the line‐by‐line results of the Ovid filter with the results of the translation. We revised the filter. We identified differences between database versions including records with different publication years and subject headings. Some records were in Embase in one interface but not in the other. We encountered expected interface differences relating to proximity operators. We also encountered unexpected interface issues around truncation and the use of the original title or original abstract field. Discussion: Filter conversion is challenging and time consuming revealing unexpected differences in interfaces and databases. Careful planning can pre‐empt some issues, but others may only emerge during testing. We identified interface anomalies that have led database publishers to review aspects of the way their interfaces work. Conclusions: Translators should be vigilant for known and unknown differences in both interfaces and database versions. [ABSTRACT FROM AUTHOR]

We present a Holocene record of floristic diversity and environmental change for the central Varanger Peninsula, Finnmark, based on ancient DNA extracted from the sediments of a small lake (sedaDNA). The record covers the period c. 10 700 to 3300 cal. a BP and is complemented by pollen data. Measures of species richness, sample evenness and beta diversity were calculated based on sedaDNA sampling intervals and 1000‐year time windows. We identified 101 vascular plant and 17 bryophyte taxa, a high proportion (86%) of which are still growing within the region today. The high species richness (>60 taxa) observed in the Early Holocene, including representatives from all important plant functional groups, shows that modern shrub‐tundra communities, and much of their species complement, were in place as early as c. 10 700 cal. a BP. We infer that postglacial colonization of the area occurred prior to the full Holocene, during the Pleistocene‐Holocene transition, Younger Dryas stadial or earlier. Abundant DNA of the extra‐limital aquatic plant Callitriche hermaphroditica suggests it expanded its range northward between c. 10 200 and 9600 cal. a BP, when summers were warmer than present. High values of Pinus DNA occur throughout the record, but we cannot say with certainty if they represent prior local presence; however, pollen influx values >500 grains cm−2 a−1 between c. 8000 and 7300 cal. a BP strongly suggest the presence of pine woodland during this period. As the site lies beyond the modern tree limit of pine, it is likely that this expansion also reflects a response to warmer Early Holocene summers. [ABSTRACT FROM AUTHOR]

While there are extensive macro‐ and microfossil records of a range of plants and animals from the Quaternary, earthworms and their close relatives amongst annelids are not preserved as fossils and therefore the knowledge of their past distributions is limited. This lack of fossils means that clitellate worms (Annelida) are currently underused in palaeoecological research, even though they can provide valuable information about terrestrial and aquatic environmental conditions. Their DNA might be preserved in sediments, which offers an alternative method for detection. Here we analyse lacustrine sediments from lakes in the Polar Urals, Arctic Russia, covering the period 24 000–1300 cal. a BP, and NE Norway, covering 10 700–3300 cal. a BP, using a universal mammal 16S rDNA marker. While mammals were recorded using the marker (reindeer was detected twice in the Polar Urals core at 23 000 and 14 000 cal. a BP, and four times in the Norwegian core at 11 000 cal. a BP and between 3600–3300 cal. a BP), worm extracellular DNA 'bycatch' was rather high. In this paper we present the first reported worm detection from ancient DNA. Our results demonstrate that both aquatic and terrestrial clitellates can be identified in late‐Quaternary lacustrine sediments, and the ecological information retrievable from this group warrants further research with a more targeted approach. [ABSTRACT FROM AUTHOR]

Abstract: Beringia (eastern Asia, Alaska, northwest Canada) has been a land‐bridge dispersal route between Asia and North America intermittently since the Mesozoic Era. The Quaternary, the most recent period of exchange, is characterized by large, geologically rapid climate fluctuations and sea‐level changes that alternately expose and inundate the land‐bridge region. Insights into how Quaternary land‐bridge geography has controlled species exchange and assembly of the North American flora comes from focusing on a restricted community with narrow ecological tolerances: species that are today restricted to isolated steppe habitats (dry grasslands) in the Subarctic. We evaluated (i) potential controls over current spatial distributions of steppe plants and their pollinators in Alaska and Yukon and (ii) their ecological distributions in relation to potential biogeographic histories. Taxa present in North America that are disjunct from Asia tended to have larger altitudinal ranges (tolerating colder temperatures) than taxa disjunct from farther south in North America, which were largely restricted to the warmest, lowest‐elevation sites. Ecological findings support the following biogeographic scenarios. Migration from Asia via the land‐bridge occurred during Quaternary glacial periods when conditions were colder and drier than today. While a corridor for migration of cold‐tolerant species of cold steppe and tundra, the land bridge acted as a filter that excluded warmth‐demanding species. Migration from North America occurred under warm, dry interglacial conditions; thermophilous North American disjuncts taking this route may have long histories in Beringia, or they may have migrated recently during the relatively warm and dry early Holocene, when forest cover was incomplete. [ABSTRACT FROM AUTHOR]

"Arctic greening" will alter vegetation quantity and quality in northern watersheds, with possible consequences for lake metabolic balance. We used paleolimnology from six Arctic lakes in Greenland, Norway, and Alaska to develop a conceptual model describing how climate‐driven shifts in terrestrial vegetation (spanning herb to boreal forest) influence lake autotrophic biomass (as chlorophyll and carotenoid pigments). Major autotrophic transitions occurred, including (1) optimal production of siliceous algae and cyanobacteria/chlorophytes at intermediate vegetation cover (dwarf shrub and Betula; dissolved organic carbon (DOC) range of 2–4 mg L−1), below and above which UVR exposure (DOC; < 2 mgL−1) and light extinction (DOC; > 4 mgL−1), respectively limit algal biomass, (2) an increase in potentially mixotrophic cryptophytes with higher forest cover and allochthonous carbon supply. Vegetation cover appears to influence lake autotrophs by changing influx of (colored) dissolved organic matter which has multiple interacting roles—as a photoprotectant—in light attenuation and in macronutrient (carbon, nitrogen) supply. [ABSTRACT FROM AUTHOR]

Sedimentary DNA (sedDNA) has recently emerged as a new proxy for reconstructing past vegetation, but its taphonomy, source area and representation biases need better assessment. We investigated how sedDNA in recent sediments of two small Scottish lakes reflects a major vegetation change, using well-documented 20th Century plantations of exotic conifers as an experimental system., We used next-generation sequencing to barcode sedDNA retrieved from subrecent lake sediments. For comparison, pollen was analysed from the same samples., The sedDNA record contains 73 taxa (mainly genus or species), all but one of which are present in the study area. Pollen and sedDNA shared 35% of taxa, which partly reflects a difference in source area. More aquatic taxa were recorded in sedDNA, whereas taxa assumed to be of regional rather than local origin were recorded only as pollen., The chronology of the sediments and planting records are well aligned, and sedDNA of exotic conifers appears in high quantities with the establishment of plantations around the lakes. SedDNA recorded other changes in local vegetation that accompanied afforestation. There were no signs of DNA leaching in the sediments or DNA originating from pollen. [ABSTRACT FROM AUTHOR]

Uncertainty about the geological processes that deposited syngenetically frozen ice-rich silt ( yedoma) across hundreds of thousands of square kilometres in central and northern Siberia fundamentally limits our understanding of the Pleistocene geology and palaeoecology of western Beringia, the sedimentary processes that led to sequestration of hundreds of Pg of carbon within permafrost and whether yedoma provides a globally significant record of ice-age atmospheric conditions or just regional floodplain activity. Here, we test the hypotheses of aeolian versus waterlain deposition of yedoma silt, elucidate the palaeoenvironmental conditions during deposition and develop a conceptual model of silt deposition to clarify understanding of yedoma formation in northern circumpolar regions during the Late Pleistocene. This is based on a field study in 2009 of the Russian stratotype of the 'Yedoma Suite', at Duvanny Yar, in the lower Kolyma River, northern Yakutia, supplemented by observations that we have collected there and at other sites in the Kolyma Lowland since the 1970s. We reconstruct a cold-climate loess region in northern Siberia that forms part of a vast Late Pleistocene permafrost zone extending from northwest Europe across northern Asia to northwest North America, and that was characterised by intense aeolian activity. Five litho- and cryostratigraphic units are identified in yedoma remnant 7E at Duvanny Yar, in ascending stratigraphic order: (1) massive silt, (2) peat, (3) stratified silt, (4) yedoma silt and (5) near-surface silt. The yedoma silt of unit 4 dominates the stratigraphy and is at least 34 m thick. It is characterised by horizontal to gently undulating subtle colour bands but typically lacks primary sedimentary stratification. Texturally, the yedoma silt has mean values of 65 ± 7 per cent silt, 15 ± 8 per cent sand and 21 ± 4 per cent clay. Particle size distributions are bi- to polymodal, with a primary mode of about 41 μm (coarse silt) and subsidiary modes are 0.3-0.7 μm (very fine clay to fine clay), 3-5 μm (coarse clay to very fine silt), 8-16 μm (fine silt) and 150-350 μm (fine sand to medium sand). Semidecomposed fine plant material is abundant and fine in-situ roots are pervasive. Syngenetic ice wedges, cryostructures and microcryostructures record syngenetic freezing of the silt. An age model for silt deposition is constructed from 47 pre-Holocene accelerator mass spectrometry (AMS) 14C ages, mostly from in-situ roots and from three optically stimulated luminescence (OSL) ages of quartz sand grains. The 14C ages indicate that silt deposition extends from 19 000 ± 300 cal BP to 50 000 cal BP or beyond. The OSL ages range from 21.2 ± 1.9 ka near the top of the yedoma to 48.6 ± 2.9 ka near the bottom, broadly consistent with the 14C age model. Most of the yedoma silt in unit 4 at Duvanny Yar constitutes cryopedolith (sediment that has experienced incipient pedogenesis along with syngenetic freezing). Mineralised and humified organic remains dispersed within cryopedolith indicate incipient soil formation, but distinct soil horizons are absent. Five buried palaeosols and palaeosol 'complexes' are identified within cryopedolith on the basis of sedimentary and geochemical properties. Magnetic susceptibility, organic content, elemental concentrations and ratios tend to deviate from average values of these parameters at five levels in unit 4. The cryopedolith-palaeosol sequence accreted incrementally upwards on a vegetated palaeo-land surface with a relief of at least several metres, preserving syngenetic ground ice in the aggrading permafrost. Pollen spectra dated to between about 17 000 and 25 000 14C BP characteristically have frequencies of 20-60 per cent tree/shrub pollen (mainly Betula and Pinus) and 20-60 per cent graminoids, predominantly Poaceae, plus forbs, whereas spectra dated to about 30 000-33 000 14C BP have lower values of woody taxa (about 10%) and are dominated by graminoids (mainly Poaceae), forbs (particularly Caryophyllaceae and Asteraceae) and Selaginella rupestris. The latter are more typical of Last Glacial Maximum (LGM) samples reported elsewhere in Siberia, and the unusually high arboreal pollen values in the LGM yedoma at Duvanny Yar are attributed to long-distance transport of pollen. Three hypotheses concerning the processes and environmental conditions of yedoma silt deposition at Duvanny Yar are tested. The alluvial-lacustrine hypothesis and the polygenetic hypothesis are both discounted on sedimentary, palaeoenvironmental, geocryological and palaeoecological grounds. The loessal hypothesis provides the only reasonable explanation to account for the bulk of the unit 4 yedoma silt at this site. Supporting the loessal interpretation are sedimentological and geocryological similarities between the Duvanny Yar loess-palaeosol sequence and cold-climate loesses in central and northern Alaska, the Klondike (Yukon), western and central Siberia and northwest Europe. Differences between loess at Duvanny Yar and that in western and central Siberia and northwest Europe include the persistence of permafrost and the abundance of ground ice and fine in-situ roots within the yedoma. Modern analogues of cold-climate loess deposition are envisaged at a local scale in cold, humid climates where local entrainment and deposition of loess are generally restricted to large alluvial valleys containing rivers that are glacially sourced or drain areas containing Late Pleistocene glacial deposits, and thus glacially ground silt. The Duvanny Yar yedoma shares sedimentological and geocryological features with yedoma interpreted as ice-rich loess or reworked loess facies at Itkillik (northern Alaska) and in the central Yakutian lowland, and with yedoma in the Laptev Sea region and the New Siberian Archipelago. It is therefore suggested that many lowland yedoma sections across Beringia are primarily of aeolian origin (or consist of reworked aeolian sediments), although other depositional processes (e.g. alluvial and colluvial) may account for some yedoma sequences in river valleys and mountains. A conceptual model of yedoma silt deposition at Duvanny Yar as cold-climate loess in Marine Isotope Stage (MIS) 3 and MIS 2 envisages summer or autumn as the main season of loess deposition. In summer, the land surface was snow-free, unfrozen and relatively dry, making it vulnerable to deflation. Graminoids, forbs and biological soil crust communities trapped and stabilised windblown sediments. Loess accretion resulted from semicontinuous deposition of fine background particles and episodic, discrete dust storms that deposited coarse silt. Winter was characterised by deep thermal contraction cracking beneath thin and dusty snow covers, and snow and frozen ground restricted deflation and sediment trapping by dead grasses. Sources of loess at Duvanny Yar potentially include: (1) sediments and weathered bedrock on uplands to the east, south and southwest of the Kolyma Lowland; (2) alluvium deposited by rivers draining these uplands; and (3) sediments exposed in the Khallerchin tundra to the north and on the emergent continental shelf of the East Siberian Sea. Glacially sourced tributaries of the palaeo-Kolyma River contributed glacially ground silt into channel and/or floodplain deposits, and some of these were probably reworked by wind and deposited as loess in the Kolyma Lowland. The palaeoenvironmental reconstruction of the sedimentary sequence at Duvanny Yar is traced from MIS 6 to the late Holocene. It includes thermokarst activity associated with alas lake development in the Kazantsevo interglacial (MIS 5e), loess accumulation, pedogenesis and syngenetic permafrost development, possibly commencing in the Zyryan glacial (70 000-55 000 cal BP) and extending through the Karginsky interstadial (55 000-25 000 cal BP) and Sartan glacial (25 000-15 000 cal BP), cessation of yedoma silt deposition during the Lateglacial, renewed thermokarst activity in the early Holocene, and permafrost aggradation in the mid to late Holocene. Beringian coastlands from northeast Yakutia through the north Alaskan Coastal Plain to the Tuktoyaktuk Coastlands (Canada) were characterised by extensive aeolian activity (deflation, loess, sand dunes, sand sheets, sand wedges) during MIS 2. Siberian and Canadian high-pressure cells coupled with a strengthened Aleutian low-pressure cell would have created enhanced pressure gradient-driven winds sufficient to entrain sediment on a regional scale. Summer winds are thought to have deflated sediment exposed on the East Siberian Sea shelf and deposited silt as a distal aeolian facies to the south. Additionally, stronger localised winds created by local downslope gravity flows (katabatic winds) may have entrained sediment. Local katabatic winds in summer may have transported silt generally northwards towards the Kolyma Lowland, particularly during times of extended upland glaciation in the North Anyuy Range to the east during the Zyryan (MIS 4) period, whereas winter winds carried limited amounts of silt generally southwards as a result of pressure gradient forces. The Duvanny Yar yedoma is part of a subcontinental-scale region of Late Pleistocene cold-climate loess. One end member, exemplified by the yedoma at Duvanny Yar, was loess rich in syngenetic ground ice (Beringian yedoma). The other, exemplified by loess in northwest Europe, was ice-poor and subject to complete permafrost degradation at the end of the last ice age. These end members reflect a distinction between enduring cold continuous permafrost conditions leading to stacked ice-rich transition zones and large syngenetic ice wedges in much of Beringia versus conditions oscillating between cold permafrost, warm permafrost and seasonal frost, leading to repeated permafrost thaw and small ice-wedge pseudomorphs in northwest Europe. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aim To use a variety of data sources to infer how northern boreal trees recovered their range upon deglaciation and/or Holocene warming. Location Scandinavia, Alaska/north-west Canada (eastern Beringia). Methods Mapped fossil occurrences for Picea (spruce) were assessed against available palaeoenvironmental and phylogeographic information. Results For Scandinavia, Last Glacial Maximum ( LGM) evidence of Picea is confined to one DNA record, but late-glacial and early-Holocene records include scattered macrofossils. Holocene pollen data show a clear east-west increase to high values. A haplotype unique to the Scandinavian Peninsula is recognized. For eastern Beringia pre- and post- LGM macrofossils occur, but the LGM fossil record comprises only scattered low pollen values. Early Holocene pollen values increase markedly c. 11 cal yr bp (north-west Canada) and c. 10 kcal yr bp (central Alaska). Also at this time three sites on the Bering Land Bridge indicate the presence of Picea where it is now absent. Several unique regional haplotypes were recorded; while most are rare one is common in some modern populations. Main conclusions Small Picea populations probably occurred in pre- Holocene Scandinavia, but pollen patterns argue against immediate expansion with the onset of warmer conditions. Despite relatively weak fossil evidence, refugial populations are also probable in eastern Beringia, particularly given the extent of unglaciated terrain. Post-glacial pollen patterns are more nuanced, suggesting two spatially and temporally distinct expansions, one possibly consistent with a unique central Alaskan haplotype, and subsequent westerly 'filling-in'. The presence of macrofossils and/or neutral markers does not require that current northern populations are derived primarily from refugial ones, particularly where pollen patterns show delayed directional expansion of large populations though time. Refugial populations initially responded weakly to major post-glacial environmental change; if subject to genetic isolation and strong selection pressure they may have had little potential to do otherwise, instead being largely replaced by in-migrating populations with greater genetic diversity. [ABSTRACT FROM AUTHOR]

Contents [ABSTRACT FROM AUTHOR]

The taxonomic and ecological diversity of ancient fungal communities was assessed by combining next generation sequencing and metabarcoding of DNA preserved in permafrost. Twenty-six sediment samples dated 16 000-32 000 radiocarbon years old from two localities in Siberia were analysed for fungal ITS. We detected 75 fungal OTUs from 21 orders representing three phyla, although rarefaction analyses suggested that the full diversity was not recovered despite generating an average of 6677 ± 3811 (mean ± SD) sequences per sample and that preservation bias likely has considerable effect on the recovered DNA. Most OTUs (75.4%) represented ascomycetes. Due to insufficient sequencing depth, DNA degradation and putative preservation biases in our samples, the recovered taxa probably do not represent the complete historic fungal community, and it is difficult to determine whether the fungal communities varied geographically or experienced a composition shift within the period of 16 000-32 000 bp. However, annotation of OTUs to functional ecological groups provided a wealth of information on the historic communities. About one-third of the OTUs are presumed plant-associates (pathogens, saprotrophs and endophytes) typical of graminoid- and forb-rich habitats. We also detected putative insect pathogens, coprophiles and keratinophiles likely associated with ancient insect and herbivore faunas. The detection of putative insect pathogens, mycoparasites, aquatic fungi and endophytes broadens our previous knowledge of the diversity of fungi present in Beringian palaeoecosystems. A large group of putatively psychrophilic/psychrotolerant fungi was also detected, most likely representing a modern, metabolically active fungal community. [ABSTRACT FROM AUTHOR]

Metabarcoding approaches use total and typically degraded DNA from environmental samples to analyse biotic assemblages and can potentially be carried out for any kinds of organisms in an ecosystem. These analyses rely on specific markers, here called metabarcodes, which should be optimized for taxonomic resolution, minimal bias in amplification of the target organism group and short sequence length. Using bioinformatic tools, we developed metabarcodes for several groups of organisms: fungi, bryophytes, enchytraeids, beetles and birds. The ability of these metabarcodes to amplify the target groups was systematically evaluated by (i) in silico PCRs using all standard sequences in the EMBL public database as templates, (ii) in vitro PCRs of DNA extracts from surface soil samples from a site in Varanger, northern Norway and (iii) in vitro PCRs of DNA extracts from permanently frozen sediment samples of late-Pleistocene age (∼16 000-50 000 years bp) from two Siberian sites, Duvanny Yar and Main River. Comparison of the results from the in silico PCR with those obtained in vitro showed that the in silico approach offered a reliable estimate of the suitability of a marker. All target groups were detected in the environmental DNA, but we found large variation in the level of detection among the groups and between modern and ancient samples. Success rates for the Pleistocene samples were highest for fungal DNA, whereas bryophyte, beetle and bird sequences could also be retrieved, but to a much lesser degree. The metabarcoding approach has considerable potential for biodiversity screening of modern samples and also as a palaeoecological tool. [ABSTRACT FROM AUTHOR]

Analyses of degraded DNA are typically hampered by contamination, especially when employing universal primers such as commonly used in environmental DNA studies. In addition to false-positive results, the amplification of contaminant DNA may cause false-negative results because of competition, or bias, during the PCR. In this study, we test the utility of human-specific blocking primers in mammal diversity analyses of ancient permafrost samples from Siberia. Using quantitative PCR (qPCR) on human and mammoth DNA, we first optimized the design and concentration of blocking primer in the PCR. Subsequently, 454 pyrosequencing of ancient permafrost samples amplified with and without the addition of blocking primer revealed that DNA sequences from a diversity of mammalian representatives of the Beringian megafauna were retrieved only when the blocking primer was added to the PCR. Notably, we observe the first retrieval of woolly rhinoceros ( Coelodonta antiquitatis) DNA from ancient permafrost cores. In contrast, reactions without blocking primer resulted in complete dominance by human DNA sequences. These results demonstrate that in ancient environmental analyses, the PCR can be biased towards the amplification of contaminant sequences to such an extent that retrieval of the endogenous DNA is severely restricted. The application of blocking primers is a promising tool to avoid this bias and can greatly enhance the quantity and the diversity of the endogenous DNA sequences that are amplified. [ABSTRACT FROM AUTHOR]

Background/aim: Routinely using outcome measures as an integral component of practice has been encouraged for decades yet has not been widely adopted. There are many reasons to measure outcomes yet any positive effect of measurement on our programs or clients has not been substantiated. If the time-consuming nature of outcome measurement is to be encouraged, we need to begin addressing larger questions of the value of outcome measurement on care and outcomes. This cohort study evaluated the impact of routinely administering the Canadian Occupational Performance Measure on client outcomes on a geriatric rehabilitation unit. Methods: Changes in Functional Independence Measure™ scores between an experimental group (n = 45) that received the routine use of the Canadian Occupational Performance Measure for evaluation/planning versus a historical comparison group (n = 58) that received ‘usual’ care were analysed using generalised linear modeling. Results: Both groups had significant changes in Functional Independence Measure™ scores over time. Results for differences between groups were inconclusive with a significantly underpowered analysis; however, results suggest that a medium to large effect of this intervention cannot be expected. Conclusions: Results are significant for the field of routine outcome measurement, suggesting that when adding the Canadian Occupational Performance Measure to routine assessment within an inpatient rehabilitation setting, substantially improved Functional Independence Measure™ score outcomes should not be expected. The value of routine outcome measurement on client outcomes remains largely unexplored. Routinely, using outcome measures requires additional research to determine the specific benefits to our programs and client outcomes. [ABSTRACT FROM AUTHOR]

Background/aim: Evidence that the physical environment is a fall risk factor in older adults is inconsistent. The study evaluated and summarised evidence of the physical environment as a fall risk factor. Methods: Eight databases (1985–2006) were searched. Investigators evaluated quality of two categories (cross-sectional and cohort) of studies, extracted and analysed data. Results: Cross-sectional: falls occur in a variety of environments; gait aids were present in approximately 30% of falls. Cohort: Home hazards increased fall risk (odds ratio (OR) = 1.15; 95% confidence interval (CI): 0.97–1.36) although not significantly. When only the high quality studies were included, the OR = 1.38 (95% CI: 1.03–1.87), which was statistically significant. Use of mobility aids significantly increased fall risk in community (OR = 2.07; 95% CI: 1.59–2.71) and institutional (OR = 1.77; 95% CI: 1.66–1.89) settings. Conclusions: Home hazards appear to be a significant risk factor in older community-dwelling adults, although they may present the greatest risk for persons who fall repeatedly. Future research should examine relationships between mobility impairments, use of mobility aids and falls. [ABSTRACT FROM AUTHOR]

At northern high latitudes, biosphere responses to and interactions with climate warming are expected to be significant during the 21st century. Most predictions of climate-biosphere interactions rely on experiments and observations in contemporary landscapes, e.g., modem distributions of vegetation types and their structural features are used to delimit potential biosphere-atmosphere feedbacks. Paleorecords look beyond the present to examine vegetation configurations under climatic regimes that approximate future scenarios. To enhance the knowledge of arctic and subarctic ecosystems under varying climatic conditions, we analyzed pollen and macrofossil data from Beringia (northeast Siberia, Alaska, and northwest Canada; 130° E to 130° W) over the past 21 000 years, with a focus on structural and functional features of the vegetation. During the early Holocene (∼ 13 000- 10 000 cal yr BP), shrub tundra ecosystems responded to climate warming through a shift from shrub tundra to deciduous forest or woodland. Early-Holocene vegetation was structurally, and hence functionally, novel compared with today's dominant vegetation types. "Modern" boreal forest developed in the mid-Holocene (∼ 10 000-6000 cal yr BP), when evergreen conifers expanded in much of the region. The shift froth tundra to deciduous forest could have happened rapidly and in situ as the result of individual (phenotypic) and/ or population-scale responses to climate warming. Because the structural and functional properties of deciduous forest differ from those of evergreen coniferous forest and tundra, deciduous boreal forest should be included in the range of future scenarios used to assess the probable feedbacks of vegetation to the climatic system that result from global warming at northern high latitudes. [ABSTRACT FROM AUTHOR]

Beringia, far north-eastern Siberia and north-western North America, was largely unglaciated during the Pleistocene. Although this region has long been considered an ice-age refugium for arctic herbs and shrubs, little is known about its role as a refugium for boreal trees and shrubs during the last glacial maximum (LGM,c. 28,000–15,000 calibrated years before present). We examine mapped patterns of pollen percentages to infer whether six boreal tree and shrub taxa (Populus,Larix,Picea,Pinus,Betula,Alnus/Duschekia) survived the harsh glacial conditions within Beringia.Extensive networks of pollen records have the potential to reveal distinctive temporal–spatial patterns that discriminate between local- and long-distance sources of pollen. We assembled pollen records for 149 lake, peat and alluvial sites from the Palaeoenvironmental Arctic Sciences database, plotting pollen percentages at 1000-year time intervals from 21,000 to 6000 calibrated years before present. Pollen percentages are interpreted with an understanding of modern pollen representation and potential sources of long-distance pollen during the glacial maximum. Inferences from pollen data are supplemented by published radiocarbon dates of identified macrofossils, where available.Pollen maps for individual taxa show unique temporal-spatial patterns, but the data for each taxon argue more strongly for survival within Beringia than for immigration from outside regions. The first increase ofPopuluspollen percentages in the western Brooks Ranges is evidence thatPopulustrees survived the LGM in central Beringia. Both pollen and macrofossil evidence supportLarixsurvival in western Beringia (WB), but data forLarixin eastern Beringia (EB) are unclear. Given the similar distances of WB and EB to glacial-age boreal forests in temperate latitudes of Asia and North America, the widespread presence ofPiceapollen in EB andPinuspollen in WB indicates thatPiceaandPinussurvived within these respective regions.Betulapollen is broadly distributed but highly variable in glacial-maximum samples, suggesting thatBetulatrees or shrubs survived in restricted populations throughout Beringia.Alnus/Duschekiapercentages show complex patterns, but generally support a glacial refugium in WB.Our interpretations have several implications, including: (1) the rapid post-glacial migration rate reported forPiceain western Canada may be over estimated, (2) the expansion of trees and shrubs within Beringia should have been nearly contemporaneous with climatic change, (3) boreal trees and shrubs are capable of surviving long periods in relatively small populations (at the lower limit of detection in pollen data) and (4) long-distance migration may not have been the predominant mode of vegetation response to climatic change in Beringia. [ABSTRACT FROM AUTHOR]

Summary Galactomannan biosynthesis in vitro is catalysed by membrane preparations from developing fenugreek seed endosperms. Two enzymes interact: a GDP-mannose dependent (1→4)-β-d-mannan synthase and a UDP-galactose dependent (1→6)-α-d-galactosyltransferase. The statistical distribution of galactosyl substituents along the mannan backbone, and the degree of galactose substitution of the primary product of galactomannan biosynthesis appear to be regulated by the specificity of the galactosyltransferase. We now report the detergent solubilisation of the fenugreek galactosyltransferase with retention of activity, the identification on gels of a putative 51 kDa galactosyltransferase protein, and the isolation, cloning and sequencing of the corresponding cDNA. The solubilised galactosyltransferase has an absolute requirement for added acceptor substrates. Beta-(1→4)-linked d-manno-oligosaccharides with chain lengths greater than or equal to 5 acted as acceptors, as did galactomannans of low to medium galactose-substitution. The putative galactosyltransferase cDNA encodes a 51282 Da protein, with a single transmembrane alpha helix near the N terminus. We have also confirmed the identity of the galactosyltransferase by inserting the cDNA in frame into the genome of the methylotrophic yeast Pichia pastoris under the control of an AOX promoter and the yeast alpha secretion factor and observing the secretion of galactomannan α-galactosyltransferase activity. Particularly high activities were observed when a truncated sequence, lacking the membrane-spanning helix, was expressed. [ABSTRACT FROM AUTHOR]

Studies pollination ecology and assemblage structures of 31 species of Stylidium at 25 sites in Western Australia. Variation of number of species according to study site; Variation in nectar-tube length; Variation in pollen placement; Observed niche overlaps.

M. Reynolds and M Edwards, commenting on R. J. Cebula's study of geographic differences in living costs in states with Right-to-Work Laws, seek to extend his results and explore the relevance of alternative variables. Cebula, in reply, addresses the comment and re-estimates the living cost impact of such laws, taking into account additional factors. Even after allowing for additional South/non-South differences, Cebula reports, the original basic model is resilient. [ABSTRACT FROM AUTHOR]

Site value taxation is neither a new nor a strictly western concept. Taxing land based on location was proposed in India around 300 B.C. François Quesnay, David Ricardo and John Stuart Mill were among the economists favoring land taxes but Henry George is credited with bringing it about in several areas, notably Australia. That subcontinent has experimented with the land tax on the national as well as the state and local levels but it is presently used only on the latter two. Empirical tests of the tax instrument are few. Pollock and Shoup (1977) forecast that eliminating the tax on improvements would increase investment levels by about 25 per cent in the long rim. Hutchinson (1963) found great differences in house values and stocks. This study evaluates the effects of site value taxation on the basis of multivariate regression analysis. It finds strong evidence that, where improvements are relieved of taxation and more revenues are obtained from land values, the average value of housing is significantly higher and the value of the housing stock substantially larger. [ABSTRACT FROM AUTHOR]