Tracking Fat-free Mass Changes Over a Competitive Season in Elite Soccer Players

The assessment of body composition in athletes throughout a competitive season can provide valuable information for coaches and practitioners as part of a general health assessment and to track training adaptations across a season. However, limited data are available to inform the capacity of common methods to accurately track longitudinal body composition changes in elite athletes. PURPOSE: The purpose of this study was to determine the validity of common body composition techniques and their associated prediction equations to track fat-free mass (FFM) in elite soccer players over a competitive season. METHODS: A sample of 21 elite soccer players participated in this observational, 4-timepoint study throughout a competitive season (T0 [mid-October], T1 [mid-December], T2 [mid-February], and T3 [end of April]). Participants underwent body composition assessments utilizing dual-energy X-ray absorptiometry (DXA), bioimpedance, and skinfolds. A modified 4-compartment (4C) model was produced using DXA and bioimpedance data, and several common skinfold prediction equations were also applied. Two-way repeated measures analysis of variance (ANOVA) tests were performed for FFM, with method and time as within-subject factors. Follow up testing was performed using one-way ANOVAs for simple main effects of method and time, as well as subsequent pairwise comparisons using t-tests. Statistical significance was accepted at p\u3c0.05. RESULTS: Statistically significant condition × time interactions were observed for FFM (p≤0.0005). Follow up one-way ANOVAs indicated simple main effects of time were present for FFM in all methods (p≤0.05); follow up pairwise comparisons for FFM demonstrated significant differences between time points for only four methods (DXA, 4C model, Civars equation, and Reilly equation), with the largest number of distinct changes detected via DXA. Both the Civars and Reilly equations detected increases in FFM between T0 and T3 and between T2 and T3. CONCLUSION: These findings suggest that when more advanced methods are not available, the Civars and Reilly skinfold equations may be suitable options for tracking FFM changes in elite soccer players throughout a full competitive season

Rapid Cycling and Exceptional Yield in a Metal-Organic Framework Water Harvester.

Sorbent-assisted water harvesting from air represents an attractive way to address water scarcity in arid climates. Hitherto, sorbents developed for this technology have exclusively been designed to perform one water harvesting cycle (WHC) per day, but the productivities attained with this approach cannot reasonably meet the rising demand for drinking water. This work shows that a microporous aluminum-based metal-organic framework, MOF-303, can perform an adsorption-desorption cycle within minutes under a mild temperature swing, which opens the way for high-productivity water harvesting through rapid, continuous WHCs. Additionally, the favorable dynamic water sorption properties of MOF-303 allow it to outperform other commercial sorbents displaying excellent steady-state characteristics under similar experimental conditions. Finally, these findings are implemented in a new water harvester capable of generating 1.3 L kgMOF -1 day-1 in an indoor arid environment (32% relative humidity, 27 °C) and 0.7 L kgMOF -1 day-1 in the Mojave Desert (in conditions as extreme as 10% RH, 27 °C), representing an improvement by 1 order of magnitude over previously reported devices. This study demonstrates that creating sorbents capable of rapid water sorption dynamics, rather than merely focusing on high water capacities, is crucial to reach water production on a scale matching human consumption

A 1000-year carbon isotope rainfall proxy record from South African baobab trees (Adansonia digitata L.)

A proxy rainfall record for northeastern South Africa based on carbon isotope analysis of four baobab ( Adansonia digitata L.) trees shows centennial and decadal scale variability over the last 1,000 years. The record is in good agreement with a 200-year tree ring record from Zimbabwe, and it indicates the existence of a rainfall dipole between the summer and winter rainfall areas of South Africa. The wettest period was c. AD 1075 in the Medieval Warm Period, and the driest periods were c. AD 1635, c. AD 1695 and c. AD1805 during the Little Ice Age. Decadal-scale variability suggests that the rainfall forcing mechanisms are a complex interaction between proximal and distal factors. Periods of higher rainfall are significantly associated with lower sea-surface temperatures in the Agulhas Current core region and a negative Dipole Moment Index in the Indian Ocean. The correlation between rainfall and the El Niño/Southern Oscillation Index is non-static. Wetter conditions are associated with predominantly El Niño conditions over most of the record, but since about AD 1970 this relationship inverted and wet conditions are currently associated with la Nina conditions. The effect of both proximal and distal oceanic influences are insufficient to explain the rainfall regime shift between the Medieval Warm Period and the Little Ice Age, and the evidence suggests that this was the result of a northward shift of the subtropical westerlies rather than a southward shift of the Intertropical Convergence Zone

Parks Canada’s adaptation framework and workshop approach: Lessons learned across a diverse series of adaptation workshops

In 2017, the Canadian Parks Council Climate Change Working Group, a team of federal, provincial, and territorial representatives, developed a Climate Change Adaptation Framework for Parks and Protected Areas, guiding practitioners through a simple, effective five-step adaptation process. This framework was adapted by Parks Canada into a two-day adaptation workshop approach, with 11 workshops subsequently held from September 2017 to May 2019 at Parks Canada sites in the Yukon, Quebec, Manitoba, Alberta, Nova Scotia, British Columbia, Newfoundland, and Ontario. Lessons learned from each workshop have been integrated into the approach, with the development of tools and guidance for each phase of the process, and a shareable, visual “placemat” that describes each step of the framework, acting as a map for those navigating the process

Exome-wide association study of pancreatic cancer risk

We conducted a case-control exome-wide association study to discover germline variants in coding regions that affect risk for pancreatic cancer, combining data from 5 studies. We analyzed exome and genome sequencing data from 437 patients with pancreatic cancer (cases) and 1922 individuals not known to have cancer (controls). In the primary analysis, BRCA2 had the strongest enrichment for rare inactivating variants (17/437 cases vs 3/1922 controls) (P=3.27x10(-6); exome-wide statistical significance threshold P<2.5x10(-6)). Cases had more rare inactivating variants in DNA repair genes than controls, even after excluding 13 genes known to predispose to pancreatic cancer (adjusted odds ratio, 1.35, P=.045). At the suggestive threshold (P<.001), 6 genes were enriched for rare damaging variants (UHMK1, AP1G2, DNTA, CHST6, FGFR3, and EPHA1) and 7 genes had associations with pancreatic cancer risk, based on the sequence-kernel association test. We confirmed variants in BRCA2 as the most common high-penetrant genetic factor associated with pancreatic cancer and we also identified candidate pancreatic cancer genes. Large collaborations and novel approaches are needed to overcome the genetic heterogeneity of pancreatic cancer predisposition

Existence of a stable polarized vacuum in the Bogoliubov-Dirac-Fock approximation

According to Dirac's ideas, the vacuum consists of infinitely many virtual electrons which completely fill up the negative part of the spectrum of the free Dirac operator $D^0$. In the presence of an external field, these virtual particles react and the vacuum becomes polarized. In this paper, following Chaix and Iracane ({\it J. Phys. B}, 22, 3791--3814, 1989), we consider the Bogoliubov-Dirac-Fock model, which is derived from no-photon QED. The corresponding BDF-energy takes the polarization of the vacuum into account and is bounded from below. A BDF-stable vacuum is defined to be a minimizer of this energy. If it exists, such a minimizer is solution of a self-consistent equation. We show the existence of a unique minimizer of the BDF-energy in the presence of an external electrostatic field, by means of a fixed-point approach. This minimizer is interpreted as the polarized vacuum.Comment: final version, to appear in Commun. Math. Phy

Proactivity directed toward the team and organization : the role of leadership, commitment and role-breadth self-efficacy

Employees' proactive behaviour is increasingly important for organizations seeking to adapt in uncertain economic environments. This study examined the link between leadership and proactive behaviour. We differentiated between organizational leadership and team leadership and proposed that transformational leadership by team leaders would enhance commitment to the team, which would predict team member proactivity. In contrast, transformational leadership by leaders of the organization would enhance commitment to the organization, which we expected to predict organization member proactivity. Transformational leadership on both levels was expected to increase employees' role-breadth self-efficacy, the confidence necessary to engage in proactive behaviour. Our results demonstrate the importance of leadership as an antecedent of proactive work behaviour and suggest that leadership at different levels influences proactivity via different mediators. Transformational team leaders seem to facilitate proactivity by increasing employees' confidence to initiate change. Transformational organizational leaders on the other hand increase proactivity by enhancing employees' commitment to the organization

Individual variability of wild juvenile Atlantic salmon activity patterns: effect of flow stage, temperature and habitat use.

The magnitude of variation of diel activity patterns and habitat use of wild Atlantic salmon (Salmo salar) parr was examined during the summer and autumn through a gradient of declining temperature. Fish were marked with passive integrated transponders and tracked using a large network of flatbed antennas. High interindividual variability was observed, as some individuals were predominantly nocturnal whereas others frequently changed their daily activity pattern. Overall fish activity decreased with decreasing temperature and increasing flow stage, but most of these changes in daily activity were observed in crepuscular periods. Parr used habitats with lower velocity at night than in the day during the summer, but not in the autumn. Furthermore, there was no difference between day and night habitats for fish that were cathemeral (active both day and night during a given day), so differences between day and night habitats were the result of individuals adopting different activity patterns. These results suggest that habitat interacts with activity pattern, as individuals using suboptimal habitats seem to increase daytime foraging to secure sufficient energy. Temporal and among-fish variability of activity patterns illustrate the dynamic nature of foraging decisions that may partly result from trade-offs experienced at the microhabitat scale. </jats:p

Energy's role in the extraversion (dis)advantage: How energy ties and task conflict help clarify the relationship between extraversion and proactive performance

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordWhile academic and practitioner literatures have proposed that extraverts are at an advantage in team‐based work, it remains unclear exactly what that advantage might be, how extraverts attain such an advantage, and under which conditions. Theory highlighting the importance of energy in the coordination of team efforts helps to answer these questions. We propose that extraverted individuals are able to develop more energizing relationships with their teammates and as a result are seen as proactively contributing to their team. However, problems in coordination (i.e., team task conflict) can reverse this extraversion advantage. We studied 27 project‐based teams at their formation, peak performance, and after disbandment. Results suggest that when team task conflict is low, extraverts energize their teammates and are viewed by others as proactively contributing to the team. However, when team task conflict is high, extraverts develop energizing relationships with fewer of their teammates and are not viewed as proactively contributing to the team. Our findings regarding energizing relationships and team task conflict clarify why extraversion is related to proactive performance and in what way, how, and when extraverts may be at a (dis)advantage in team‐based work