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Introduction: Frailty is conventionally diagnosed using clinical tests and self-reported assessments. However, digital health technologies (DHTs), such as wearable accelerometers, can capture physical activity and gait during daily life, enabling more objective assessments. In this study, we assess the feasibility of deploying DHTs in community-dwelling older individuals, and investigate the relationship between digital measurements of physical activity and gait in naturalistic environments and participants' frailty status, as measured by conventional assessments. Methods: Fried Frailty Score (FFS) was used to classify fifty healthy individuals as non-frail (FFS = 0, n/female = 21/11, mean ± SD age: 71.10 ± 3.59 years), pre-frail (FFS = 1–2, n/female = 23/9, age: 73.74 ± 5.52 years), or frail (FFS = 3+, n/female = 6/6, age: 70.70 ± 6.53 years). Participants wore wrist-worn and lumbar-worn GENEActiv accelerometers (Activinsights Ltd., Kimbolton, UK) during three in-laboratory visits, and at-home for 2 weeks, to measure physical activity and gait. After this period, they completed a comfort and usability questionnaire. Compliant days at-home were defined as follows: those with ≥18 h of wear time, for the wrist-worn accelerometer, and those with ≥1 detected walking bout, for the lumbar-worn accelerometer. For each at-home measurement, a group analysis was performed using a linear regression model followed by ANOVA, to investigate the effect of frailty on physical activity and gait. Correlation between at-home digital measurements and conventional in-laboratory assessments was also investigated. Results: Participants were highly compliant in wearing the accelerometers, as 94% indicated willingness to wear the wrist device, and 66% the lumbar device, for at least 1 week. Time spent in sedentary activity and time spent in moderate activity as measured from the wrist device, as well as average gait speed and its 95th percentile from the lumbar device were significantly different between frailty groups. Moderate correlations between digital measurements and self-reported physical activity were found. Conclusions: This work highlights the feasibility of deploying DHTs in studies involving older individuals. The potential of digital measurements in distinguishing frailty phenotypes, while unobtrusively collecting unbiased data, thus minimizing participants' travels to sites, will be further assessed in a follow-up study. [ABSTRACT FROM AUTHOR]

We present 40 new 10Be exposure ages of moraines and other glacial deposits left behind by the southeastern sector of the Laurentide Ice Sheet (LIS) in southern New England and New York, summarize the regional moraine record, and interpret the dataset in the context of previously published deglaciation chronologies. The regional moraine record spans the Last Glacial Maximum (LGM), with the outermost ridge of the terminal complex dating to ~26–25 ka, the innermost ridge of the terminal complex dating to ~22 ka, and a series of smaller recessional limits within ~50 km of the terminal complex dating to ~21–20.5 ka. The chronology generally agrees with independent age constraints from radiocarbon and glacial varves. A few inconsistencies among ages from cosmogenic-nuclide measurements and those from other dating methods are explained by geologic scatter where several bedrock samples and boulders from the outer terminal moraine exhibit nuclide inheritance, while exposure ages on large moraines are likely affected by postdepositional disturbance. The exposure-age chronology places the southeastern sector of the LIS at or near its maximum extent from ~26 to 21 ka, which is broadly consistent with the LGM sea-level lowstand, local and regional temperature indicators, and local summer insolation. The net change in LIS extent represented by this chronology occurred more slowly (<5 to 25 m yr-1) than retreat through the rest of New England, consistent with a slow general rise in insolation and modeled summer temperature. We conclude that the major pulse of LIS deglaciation and accelerated recession, recorded by dated glacial deposits north of the moraines discussed here, did not begin until after atmospheric CO2 increased at ~18 ka, marking the onset of Termination 1. [ABSTRACT FROM AUTHOR]

Large, resistant, quartz‐rich boulders deposited on hillslopes and in channels armour the landscape, trap sediment and influence hillslope angle and erodibility. In the Virginia Appalachians, such boulders are a significant component of hillslopes and channels. Establishing the timing of and processes responsible for bedrock fracture and boulder deposition is a critical piece of understanding the landscape as a system. In this study, we use cosmogenic 10Be exposure dating to resolve the timing of boulder deposition at three sites in the Virginia Valley and Ridge province: Gap Mountain, Brush Mountain and Little Stony Creek, and at one site in the Virginia Blue Ridge: Devil's Marbleyard. The correlation between measured boulder exposure ages (101.7 ± 6.9 ka to 10.8 ± 0.8 ka; n = 23) and the Wisconsin Glacial Stage and subsequent Laurentide Ice Sheet (LIS) deglaciation (~115–11.7 ka) suggests a periglacial origin for deposition of large hillslope and channel boulders in the Virginia Appalachians. The lack of boulder exposure ages corresponding to the Last Interglacial Stage or following Wisconsin LIS retreat suggests interglacial non‐deposition and stability. The absence of exposure ages from the penultimate Illinoian or older Quaternary Glacial Stages suggests that periglacial hillslope processes allow the landscape to be resurfaced with large boulders during each return to cold climate conditions. This cyclic resurfacing of hillslopes and channels is an example of how climatic oscillations insert disequilibrium into the landscape cycle and contributes to our appreciation of the timescales over which contemporary climate change may impact boulder dominated landscapes in rapidly warming alpine and arctic environments. [ABSTRACT FROM AUTHOR]

This article has arisen from a study involving teachers in an early childhood centre and their responses to being introduced to schema learning theory. As a former practitioner in early childhood education and in my current role in initial teacher education, I have an interest in cognitive constructivist learning theories from both developmental and sociocultural pedagogies and how these theories have changed and adapted over time. While some would suggest schema learning theory and sociocultural approaches to children's learning are pedagogically worlds apart, it is the purpose of this article to highlight the benefits and possibilities for both. Schema theory involves teachers identifying, interpreting, and extending learning while sociocultural approaches use the discourse of noticing, recognising, and responding. This article suggests when teachers use schema learning theory "within" sociocultural approaches to teaching, learning, and assessment, they are able to explore children's thinking more explicitly in their practice.

The Nipigon channels, located to the west and northwest of Lake Nipigon, Ontario, are thought to have enabled the eastward drainage of meltwater from glacial Lake Agassiz during the last deglaciation. Here we present the first direct ages of flood deposits in two of these channels using [sup.10]Be surface exposure dating. Five [sup.10]Be ages of a coarse- grained deposit near the Roaring River in the Kaiashk channel complex indicate deglaciation and cessation of water flow by ~11070 ± 430 years. To test for inherited nuclides in boulder samples, we also measured the [sup.10]Be concentrations of the undersides of two boulders at the Roaring River site. Five [sup.10]Be ages of boulders atop a large bed form near Mundell Lake in the Pillar channel complex indicate deglaciation and cessation of water flow by ~10 770 ± 240 years. Two [sup.10]Be ages of nearby bedrock are slightly younger (10 340 ± 260 and 9860 ± 270 years). The [sup.10]Be ages from the two sites are statistically indistinguishable and indicate that Laurentide Ice Sheet recession occurred rapidly in the region. We used clast diameters and channel dimensions at the Mundell Lake site to estimate paleodischarge and evaluate the possibility that meltwater drainage influenced climate conditions. We estimate a large maximum discharge of 119 000-159 000 [m.sup.3] x [s.sup.-1] at the site. However, the timing of meltwater discharge at both Roaring River and Mundell Lake is not contemporaneous with abrupt climate events. Les chenaux de Nipigon, situes a l'ouest et au nord-ouest du lac Nipigon (Ontario) auraient permis la vidange vers l'est de l'eau de fonte issue du lac glaciaire Agassiz durant la derniere deglaciation. Nous presentons les premiers ages directs de depots d'inondation dans deux de ces chenaux, obtenus par datation au [sup.10]Be de l'exposition en surface. Cinq ages [sup.10]Be d'un depot a grains grossiers situe pres de la riviere Roaring, dans le complexe de chenaux de Kaiashk, indiquent que la deglaciation et la cessation de l'ecoulement de l'eau avaient deja eu lieu vers 11070 ± 430 ans. Pour verifier la presence de nucleides herites dans des echantillons de bloc, nous avons egalement mesure les concentrations de [sup.10]Be des faces inferieures de deux blocs au site de la riviere Roaring. Cinq ages [sup.10]Be de blocs au sommet d'une grande forme de fond pres du lac Mundell dans le complexe de chenaux de Pillar indiquent que la deglaciation et la cessation de l'ecoulement de l'eau avaient deja eu lieu vers 10 770 ± 240 ans. Deux ages [sup.10]Be du substrat rocheux a proximite sont legerement plus jeunes (10 340 ± 260 et 9860 ± 270 ans). Les ages [sup.10]Be obtenus des deux sites sont statistiquement identiques et indiquent que le recul de la calotte glaciaire des Laurentides s'est effectue rapidement dans cette region. Nous avons utilise les diametres des clastes et les dimensions des chenaux au site du lac Mundell pour estimer les paleodebits et evaluer la possibilite que la vidange de l'eau de fonte ait influence les conditions climatiques. Nous estimons un important debit maximum au site, de l'ordre de 119 000 a 159 000 [m.sup.3] x [s.sup.-1]. Le moment de la vidange de l'eau de fonte tant a la riviere Roaring qu'au lac Mundell ne correspond toutefois pas a des evenements climatiques brusques. [Traduit par la Redaction], Introduction It has long been thought that channels in the areas located west of Thunder Bay and west and northwest of Lake Nipigon, Ontario (Fig. 1), served as eastern outlets [...]

Situated in the Transantarctic Mountains, western Victoria Valley is in a key position to test the late Cenozoic stability of the East Antarctic Ice Sheet, as well as that of the surrounding landscape surface. Victoria drift, which covers most of western Victoria Valley, represents a peculiar yet common type of deposit in the region. The sedimentology of Victoria drift is dominated by loose, sorted material, which preserves lacustrine algae, quite unlike tills in the Dry Valleys. Ridges characterize its morphology. Extraordinarily old ridges and mounds as well as fresh features and unweathered and perched boulders occur without apparent order. Accelerator Mass Spectrometry (AMS) radiocarbon dates of algae from within Victoria drift range from 11 054 [+ or -] 95 to >45 000 [sup.14]C yr B.P. and are not arrayed in chronological order across the drift sheet. Resting on a Miocene erosion surface, Victoria drift is the only widespread deposit in western Victoria Valley younger than ca. 14 Ma. One hypothesis is that the drift consists of moraines. The strength of this hypothesis is that it explains the arcuate form of many ridges. However, it does not explain the sedimentology, weathering characteristics, or radiocarbon dates. A second hypothesis is that Victoria drift is a unique polar glaciolacustrine sediment facies deposited by a 'lake-ice conveyer.' The morphologic features, sedimentology, weathering characteristics, and radiocarbon dates of the drift are all consistent with deposition in a perennially ice-covered lake. This second hypothesis implies polar glacial conditions during deposition of the drift sheet in order to maintain a permanently ice-covered proglacial lake. Keywords: East Antarctic Ice Sheet, geomorphology, glacial lakes, glacial sediments, lake-ice conveyer, radiocarbon dating.