Apollo 14: Some geochemical aspects

Chemical analyses were obtained for five samples of Apollo 14 regolith fines, three 14230 core samples, soil clod 14049, breccias 14305 and 14319, 14310 basalt, and some separated phases. The chemical uniformity of these Apollo 14 samples indicates thorough mixing and/or uniform source rocks. Basalt 14310 can be matched well in composition by a four to one mixture of soil and plagioclase. The Eu(2+)/Eu(3+) ratios calculated for 14310 pigeonite and plagioclase are similar to those for Apollo 12 and 15 mare-type basalt phases; this indicates similar redox conditions. Apollo 14 samples are chemically similar to Apollo 12 and 15 KREEP as distinct from Apollo 11, 12, and 15 and Luna 16 mare-type basalts

The Effects of Sleep Loss on Military Physical Performance

© 2019, Springer Nature Switzerland AG. As part of both training and active service, military members can be exposed to prolonged periods of sleep loss. Given the extent of physical and cognitive performances viewed as critical to successful military performance, such sleep disruption may present risk to health and performance. The primary aim of this narrative review was to investigate evidence on the effect of inadequate sleep on measures of aerobic capacity, anaerobic capacity, muscular strength and muscular endurance in military personnel. Sleep loss appears to have the greatest negative impact on aerobic capacity, muscular endurance and military-specific performance in military populations. The findings showed varied results for handgrip strength and anaerobic capacity, with sleep loss inducing a decrease in mean power of the upper body. In comparison to other measures of performance, lower-body muscular strength appeared to be resilient to sleep restriction. However, due to the limited evidence and inter-individual variability in results there is no clear consensus on the specific volume of sleep loss that induces significant or meaningful performance decrements. The difficulties of conducting well-designed and -controlled interventions in military populations are appreciated. However, due to the low quality of reporting and lack of control for confounders (i.e. physical activity, load carriage, prior sleep debt, motivation and energy intake) in the majority of studies, it is difficult to establish the relationship between sleep loss and physical performance in military populations

Giving ‘live’ GPS feedback to athletes: Does it alter locomotor performance during small-sided games?

Introduction Small-sided games (SSGs) are used to train physical qualities while practicing sport specific skills. Live Global Positioning Systems (GPS) data can provide feedback during these games; however, the impact of feedback on subsequent locomotor performance is unknown. This study aimed to investigate if providing ‘live’ GPS feedback to players in between bouts of SSGs altered locomotor performance. Methods Using a reverse counterbalanced design, twenty male university rugby players received either feedback or no-feedback (control) during ‘off-side’ touch rugby SSGs. Eight 5v5, 6x4 minute SSGs were played over four days (2/day) with a 20-minute rest between SSGs and at least 72-hours rest between days. Teams were assigned to feedback (4-games) with verbal feedback provided during a 2-minute between bout rest interval, or no feedback (4-games) for the day. Locomotor performance was measured via a 10 Hz GPS and variables were analysed using a linear mixed model, reported using effect sizes (ES) and 90% confidence intervals and then interpreted via magnitude-based inferences. Results Over the full SSG (6x4 min bouts) there was a possibly trivial (ES = 0.15 [-0.03, 0.34]) difference between conditions in total distance (2200 (156) vs. 2177 (186) m). There was also possibly trivial (ES = 0.18 [0.00, 0.37]) and likely trivial (ES = -0.07 [-0.27, 0.13]) differences between conditions in low- and high-speed distance. Between bouts there was a possibly or likely trivial (ES = 0.08 to 0.14) difference in total distance for bouts 2, 4, 5 and 6, with unclear (ES = -0.01 [-0.24, 0.22]) differences in bout 3. There was a likely trivial (ES = 0.11 [-0.01, 0.22]) difference in total distance covered during the first minute of each bout. Discussion In this study, verbal feedback did not alter locomotor performance in rugby players during SSGs. These data suggest that technical and tactical aspects of SSGs might reduce any ergogenic effects of feedback, although it is unknown if the type of feedback provided nullified any potential effects. Furthermore, extrinsic motivating factors such as team success are likely to be perceived as more important than locomotor performance. Future research should endeavour to investigate if these findings are consistent across other forms of feedback, bout durations, football codes, playing levels or training modalities. Conclusions Verbal feedback of distance covered during bouts of SSGs does not alter subsequent locomotor performance

Open science in archaeology

No abstract available

Neanderthal Use of Fish, Mammals, Birds, Starchy Plants and Wood 125-250,000 Years Ago

Neanderthals are most often portrayed as big game hunters who derived the vast majority of their diet from large terrestrial herbivores while birds, fish and plants are seen as relatively unimportant or beyond the capabilities of Neanderthals. Although evidence for exploitation of other resources (small mammals, birds, fish, shellfish, and plants) has been found at certain Neanderthal sites, these are typically dismissed as unusual exceptions. The general view suggests that Neanderthal diet may broaden with time, but that this only occurs sometime after 50,000 years ago. We present evidence, in the form of lithic residue and use-wear analyses, for an example of a broad-based subsistence for Neanderthals at the site of Payre, Ardèche, France (beginning of MIS 5/end of MIS 6 to beginning of MIS 7/end of MIS 8; approximately 125–250,000 years ago). In addition to large terrestrial herbivores, Neanderthals at Payre also exploited starchy plants, birds, and fish. These results demonstrate a varied subsistence already in place with early Neanderthals and suggest that our ideas of Neanderthal subsistence are biased by our dependence on the zooarchaeological record and a deep-seated intellectual emphasis on big game hunting

Investigation of recast and crack formation in laser trepanning drilling of CMSX-4 angled holes

This paper presents an experimental investigation on the influences of laser trepanning drilling process parameters on the recast layer thickness and surface crack formation in CMSX-4 nickel-based superalloy angled holes. The effects of peak power, pulse frequency and the trepanning speed as input parameters were investigated in details by varying the laser drilling conditions using Taguchi orthogonal array-based design of experiment approach. Analysis of variance identifies the significant parameters affecting the output responses. It is found that the output responses are affected mainly by the peak power and trepanning speed. The experimental results reveal that the recast layer thickness increases with the increase of peak power and trepanning speed whereas the crack number density decreases with the increase of peak power only. Pulse frequency has no significant effect on both output responses within the range of values investigated. The knowledge gained in this parametric study could be used to improve the metallurgical characteristics of laser-drilled nickel-based acute angled holes

On the conceptualization and measurement of flow

This chapter introduces in chronological order the three main measurement methods – the Flow Questionnaire, the Experience Sampling Method, and the standardized scales of the componential approach – that researchers developed and used in conducting research on the flow state. Each measurement method and underlying conceptualization is explained, and its strengths and limitations are then discussed in relation to the other measurement methods and associated conceptualizations. The analysis reveals that, although the concept of flow remained stable since its inception, the models of flow that researchers developed in conjunction with the measurement methods changed substantially over time. Moreover, the findings obtained by applying the various measurement methods led to corroborations and disconfirmations of the underlying models, and hence provided indications on how to interpret and possibly modify flow theory. The chapter then analyzes the emerging process approach, which conceptualizes and measures flow as a dynamic path rather than an object, and highlights its potential for integrating flow and creativity within the same conceptual framework. The final section outlines new directions for developing more valid and useful measurement methods that can help to advance the understanding of flow, its antecedents, and its consequences

Human occupation of northern Australia by 65,000 years ago

The time of arrival of people in Australia is an unresolved question. It is relevant to debates about when modern humans first dispersed out of Africa and when their descendants incorporated genetic material from Neanderthals, Denisovans and possibly other hominins. Humans have also been implicated in the extinction of Australia's megafauna. Here we report the results of new excavations conducted at Madjedbebe, a rock shelter in northern Australia. Artefacts in primary depositional context are concentrated in three dense bands, with the stratigraphic integrity of the deposit demonstrated by artefact refits and by optical dating and other analyses of the sediments. Human occupation began around 65,000 years ago, with a distinctive stone tool assemblage including grinding stones, ground ochres, reflective additives and ground-edge hatchet heads. This evidence sets a new minimum age for the arrival of humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans.Chris Clarkson ... Lee J. Arnold ... et al