Large Area Crop Inventory Experiment (LACIE). Intensive test site assessment report

There are no author-identified significant results in this report

2017 McDonald diagnostic criteria: A review of the evidence

The diagnosis of Multiple Sclerosis (MS) has continuously evolved, allowing for an earlier and more accurate diagnosis of MS over time. The McDonald Criteria for diagnosis of MS were originally proposed in 2001, with previous revisions in both 2005 and 2010. The International Panel on Diagnosis in MS have recently reviewed the 2010 McDonald Criteria, and made recommendations for the revised 2017 McDonald Criteria. Any revisions made relied entirely on the available evidence, and not expert opinion. In this review, we provide an overview of the recent 2017 revisions to the McDonald Criteria, focusing in particular on the motivating evidence behind the recommendations made. We also review the existing research around misdiagnosis in MS, as well as areas considered to be high priorities of research, currently lacking in sufficient evidence, which may influence future diagnostic criteria in years to come. Finally, we illustrate some clinical examples, to demonstrate the impact of new diagnostic criteria on time to MS diagnosis in a real-world setting

Dislocation structures in materials using grand-canonical minima hopping energy minimization

Modern semiconductor devices often require the use of multi-material systems in order to operate. This inevitably requires the formation of an interface where the two dissimilar materials are joined. Two such examples are quantum dots (QDs) which incorporate 3D geometries with non-planar interfaces and 2D materials which comprise single atom thick geometries. These promise to revolutionize nanoelectronics with increases in device performance and efficiency spanning applications such as photovoltaics, quantum computing, memory storage, and transistors. However, a limiting factor in the realization of such devices is the often undesirable defect formation that arises from the combination of lattice mismatched materials which motivates the study of compatible material selections and improved fabrication techniques. One way in which these discoveries can be realized is through computational modeling which can provide a thorough understanding of the energetics of accompanying defect structures and, therefore, the accompanying conditions in which they might be expected. Continuum based methods offer one solution for predicting their defect or dislocation onset. However, this implementation does not easily allow for the fine, atomistic detail needed for predicting the important core structures involved. Atomistic modeling offers a more detailed solution but the defect structure must often be assumed in order to compute the accompanying configurational energy. When the exact defect structure is unknown, methods such as molecular dynamics (MD), Monte Carlo (MC) techniques, or other ad-hoc implementations are used to find the atomistic structure with the lowest energy among all the possibilities available. Although these approaches include the detail needed to describe core structures and other complex processes, they can often fail to find minimum energy structures due to long time-scales or sampling limitations that make them computationally expensive. Also, many of these studies either neglect or inefficiently implement the relative energy contributions associated with a Grand Canonical (GC) ensemble where a much more favorable defect structure can be obtained with more or fewer atoms than the initialized system. A complete mapping of this high dimensional energy landscape can present valuable insight when predicting low energy structures associated with a specific material combination as most 2D and 3D materials have competing defect structures across a variable number of atoms. In this work, a new GC potential energy surface (GC-PES) exploration technique is presented known as the Grand-Canonical Minima Hopping (GCMH) method, which provides an efficient and adaptive energy landscape exploration for predicting the lowest energy configuration or defect structures present in a given system. Leading to the details of this new procedure, three studies are first discussed in order to highlight the role of dislocations for strain relief and the coupling that these defects have to material properties. These works include a continuum analysis of strain and band alignment in 3D GaAs/GaSb QDs, a critical thickness study in 2D h-BN/graphene heterostructures, and an investigation of moir\'e patterns in 2D materials. Following a description of the underlying Minima Hopping method (MH), the procedure behind the GCMH method is presented along with a case study on fullerene structures. Next, the importance of the atomistic representation for a PES exploration is shown and a parallelization scheme based on distributed softening is discussed. The GCMH is applied to a dislocated graphene system and the structural manifestation of several types of defects is compared to experiments

Selective influences of maximum dynamic strength and bar-power output on team sports performance: a comprehensive study of four different disciplines

This study examined the selective influences of one-repetition maximum (1RM) values [assessed in the half-squat (HS)] and bar-power production [assessed in both HS and jump squat (JS) exercises] on the physical performance of male and female team sport athletes from four different sports. Three-hundred and three elite players (31 Olympians) from four different disciplines (47 male soccer players, 58 female soccer players, 28 male handball players, 58 female handball players, 49 male rugby players, and 63 male futsal players) participated in this study. The physical tests were performed over 2 consecutive days for soccer and rugby players, and in 1 day for the remaining athletes. On the first day, rugby and soccer athletes performed squat jumps (SJ), countermovement jumps (CMJ), and HS 1RM. On the second day, they executed HS and JS tests (to assess the maximum bar-power output) and the linear and change-of-direction (COD) speed tests. For the other players, the sequence of the measurements was the same; however, they did not perform the HS exercise. Athletes were separated, using a median split analysis, into two distinct groups, according to their bar-power output in both JS and HS exercises and their performance in HS 1RM. The magnitude-based inferences method was used to examine the differences between “higher” and “lower” performance groups. Overall, the bar-power outputs were better connected to improved acceleration, speed, and jump performance than the 1RM measures. From these findings, it is possible to infer that players able to produce higher bar-power outputs are likely to sprint faster and jump higher. Therefore, coaches involved in team sports are strongly encouraged to use the bar-power method to evaluate the athletic performance of their players

One-repetition-maximum measures or maximum bar-power output: which Is more related to sport performance?

Purpose: This study compared the associations between optimum power loads and 1-repetition maximum (1RM) values (assessed in half-squat [HS] and jump squat [JS] exercises) and multiple performance measures in elite athletes. Methods: Sixty-one elite athletes (fifteen Olympians) from four different sports (track and field [sprinters and jumpers], rugby sevens, bobsled, and soccer) performed squat and countermovement jumps, HS exercise (for assessing 1RM), HS and JS exercises (for assessing bar-power output), and sprint tests (60-m for sprinters and jumpers and 40-m for the other athletes). Pearson’s product moment correlation test was used to determine relationships between 1RM and bar-power outputs with vertical jumps and sprint times in both exercises. Results: Overall, both measurements were moderately to near perfectly related to speed performance (r values varying from -0.35 to -0.69 for correlations between 1RM and sprint times, and from -0.36 to -0.91 for correlations between bar-power outputs and sprint times; P< 0.05). However, on average, the magnitude of these correlations was stronger for power-related variables, and only the bar-power outputs were significantly related to vertical jump height. Conclusions: The bar-power outputs were more strongly associated with sprint-speed and power performance than the 1RM measures. Therefore, coaches and researchers can use the bar-power approach for athlete testing and monitoring. Due to the strong correlations presented, it is possible to infer that meaningful variations in bar-power production may also represent substantial changes in actual sport performance

Traditional free-weight vs. variable resistance training applied to elite young soccer players during a short preseason: effects on strength, speed, and power performance

Maximizing the neuromuscular capacities of players is a critical challenge during short soccer preseasons. This study compared the effects of two strength-power training regimes, on the strength, speed, and power performance of elite young soccer players during a 4-week preseason. Twenty-five under-20 players from the same club were pair-matched in two training groups as follows: traditional training group (TTG) (n=13), athletes performed half-squat (HS) and jump-squat (JS) exercises as traditionally prescribed; and EB group (EBG) (n=12), athletes performed HS and JS with EB attached to the barbell. Vertical jump height, 20-m sprint velocity, change-of-direction (COD) speed, HS and JS power, and one-repetition maximum (1RM) in the HS were assessed pre, post 2-week, and post 4-week of training. An ANOVA two-way with repeated measures was used to assess the effects of both training protocols over the experimental period. Both strategies were effective for significantly improving HS and JS power (effect sizes [ES] 1.00 - 1.77), HS 1RM (ES = 1.68 and 1.51 for TTG and EBG, respectively), vertical jumping ability (ES 0.37 - 0.65), and COD speed (ES = 0.81 and 0.39 for TTG and EBG, respectively), when comparing pre- and post-measures. In contrast, both TTG and EBG failed to increase 20-m sprint velocity (ES ranging between -0.54 and 0.23). In conclusion, both training schemes were able to improve the strength and power performance, but not the sprint capacity of young soccer players. To accelerate strength gains over very-short time periods (i.e., 2-week), variable resistance training may be advantageous. Conversely, to optimize power adaptations in ballistic exercises across a similar time period, traditional FW training may be preferred

Maximum strength, relative strength, and strength deficit: relationships with performance and differences between elite sprinters and professional rugby union players

Purpose: To test the relationships between maximum and relative strength (MS and RS), absolute and relative peak force (PF and RPF), and strength deficit (SDef), with sprint and jump performance, and to compare these mechanical variables between elite sprinters and professional rugby union players. Methods: Thirty-five male rugby union players and thirty male sprinters performed vertical jumps, 30-m sprint, and the half-squat one-repetition maximum (1RM) assessment, where these force-related parameters were collected. Pearson correlation coefficient was used to test the relationships among the variables. An independent t-test and magnitude-based inferences compared the mechanical variables between sprinters and rugby players. Results: Almost certain significant differences were observed for jump and sprint performance between the groups (P < 0.0001). Rugby union players demonstrated a likely significant higher MS (P = 0.03), but a very likely lower RS (P = 0.007) than sprinters. No significant differences were observed for PF between them. Sprinters exhibited an almost certain significant higher RPF than rugby players (P < 0.0001). Furthermore, rugby players demonstrated almost certain to likely significant higher SDef from 40 to 70% 1RM (P < 0.05) compared to sprinters. Overall, all strength-derived parameters were significantly related to functional performance. Conclusions: Elite sprinters present higher levels of RS and RPF, lower levels of SDef, and superior sprint and jump performance than professional rugby players. Relative strength-derived values (RS and RPF) and SDef are significantly associated with speed-power measures and may be used as effective and practical indicators of athletic performance