Magnetomechanical performance and mechanical properties of Ni-Mn-Ga ferromagnetic shape memory alloys

A Ni-Mn-Ga ferromagnetic shape memory alloy was tested for strain versus applied field and strain versus stress. Field- induced strains up to 6 percent were measured with a hysteresis of about 160 kA/m. The results are compared with the predictions of modeling with a focus on hysteresis. The model is applied to the case in which the magnetic external field and external load are orthogonal to each other. It predicts the magneto-mechanical hysteresis as a function of the yield stress in a twinned martensite. Magnetization versus applied field was measured on a sample that was mechanically constrained in order to understand the magnetization behavior of the sample in the absence of twin motion. These measurements give the magnetic anisotropy and are used to estimate the demagnetization fields. The measured behavior of strain with stress at constant field is approximated by the model

SAM: A Tool for Measurement of Moderate to Vigorous Physical Activity (MVPA) in School Physical Education

Int J Exerc Sci 5(2) : 127-135, 2012. Observational methods have been a primary methodology used by physical educators for assessing teacher and student behaviors in school physical education (PE) classes for over 30 years. Observational instruments traditionally used in PE are economical, but are time intensive and complicated. Recently national PE recommendations have been promoted to encourage practitioners to achieve ≥ 50% of PE class in moderate to vigorous physical activity (MVPA). The purpose of this preliminary study was to develop, validate, and test the reliability of the Simple Activity Measurement (SAM) instrument for assessing MVPA during school PE classes. Students (N=36, representing grades 3-10) from a convenient sample of schools in San Antonio, TX were randomly selected to wear SUUNTOTM heart rate (HR) monitors during PE classes as an MVPA intensity measure, and the SAM instrument was used to observe 6 classes (N=281 students) for MVPA each minute using the SAM 0-10 scale. The SAM instrument was found to be a significant predictor for HR (r=0.555, r2=0.308, p\u3c0.05) using linear regression, and the intra class correlation coefficient to test reliability was found to be R=0.803, p\u3c0.05. Students averaged 88.5 % of class time spent in MVPA at the elementary level and only 36.5 % of class time spent in MVPA at the high school level. The results of this preliminary study indicate that the SAM has promise to provide school PE evaluators with an effective economical observation tool to document minutes of student MVPA in PE classes, and to promote accountability with national MVPA recommendations

Dust-Gas Scaling Relations and OH Abundance in the Galactic ISM

Observations of interstellar dust are often used as a proxy for total gas column density $N_\mathrm{H}$. By comparing $\textit{Planck}$ thermal dust data (Release 1.2) and new dust reddening maps from Pan-STARRS 1 and 2MASS (Green et al. 2018), with accurate (opacity-corrected) HI column densities and newly-published OH data from the Arecibo Millennium survey and 21-SPONGE, we confirm linear correlations between dust optical depth $\tau_{353}$, reddening $E(B{-}V)$ and the total proton column density $N_\mathrm{H}$ in the range (1$-$30)$\times$10$^{20}$cm$^{-2}$, along sightlines with no molecular gas detections in emission. We derive an $N_\mathrm{H}$/$E(B{-}V)$ ratio of (9.4$\pm$1.6)$\times$10$^{21}$cm$^{-2}$mag$^{-1}$ for purely atomic sightlines at $|b|$$>$5$^{\circ}$, which is 60$\%$ higher than the canonical value of Bohlin et al. (1978). We report a $\sim$40$\%$ increase in opacity $\sigma_{353}$=$\tau_{353}$/$N_\mathrm{H}$, when moving from the low column density ($N_\mathrm{H}$$<$5$\times$10$^{20}$cm$^{-2}$) to moderate column density ($N_\mathrm{H}$$>$5$\times$10$^{20}$cm$^{-2}$) regime, and suggest that this rise is due to the evolution of dust grains in the atomic ISM. Failure to account for HI opacity can cause an additional apparent rise in $\sigma_{353}$, of the order of a further $\sim$20$\%$. We estimate molecular hydrogen column densities $N_{\mathrm{H}_{2}}$ from our derived linear relations, and hence derive the OH/H$_2$ abundance ratio of $X_\mathrm{OH}$$\sim$1$\times$10$^{-7}$ for all molecular sightlines. Our results show no evidence of systematic trends in OH abundance with $N_{\mathrm{H}_{2}}$ in the range $N_{\mathrm{H}_{2}}$$\sim$(0.1$-$10)$\times$10$^{21}$cm$^{-2}$. This suggests that OH may be used as a reliable proxy for H$_2$ in this range, which includes sightlines with both CO-dark and CO-bright gas.Comment: The revised manuscript is accepted for publication in The Astrophysical Journa

Sensitivity of Prescribing High-Intensity, Interval Training Using the Critical Power Concept

International Journal of Exercise Science 8(3): 202-212, 2015. The critical power (CP) concept enables the calculation of time to exhaustion (tLIM) for a given power output above CP using the equation of tLIM = W’/(power – CP), where W’ is the curvature constant, and CP is the asymptote for the power-tLIM relationship. The CP concept offers great promise for prescribing high-intensity interval training (HIIT); however, knowledge on the concept’s sensitivity is lacking (i.e., how much of a difference in W’ expenditure is needed to evoke different metabolic responses). We tested if two different power-tLIM configurations expending identical proportions of W’ would evoke different end-exercise oxygen uptake (VO2) and heart rate (HR) values. Five men and five women completed a graded exercise test, 3-min all-out exercise tests, and intervals prescribed to deplete either 70 or 80% of W’ on separate visits. Consistency statistics of intraclass correlation (ICC a), standard error of measure (SEM), and coefficient of variation (CV) were calculated on end-exercise values. End-exercise VO2 were similar for the 3.5- and 5-min bouts, depleting 70% of W’ (ICC a = 0.91, SEM = 3.23 mL·kg-1·min-1, CV = 8.1%) and similar for the 4- and 5-min bouts, depleting 80% of W’ (ICC a = 0.95, SEM = 2.34 mL·kg-1·min-1, CV = 8.1%). No VO2 differences were observed between trials or conditions (p = 0.58). Similarly, HR values (~181 b·min-1) did not differ between trials or conditions (p = 0.45). Use of the CP concept for HIIT prescriptions of different power-tLIM configurations evokes similar end-exercise VO2 values on a given day. Our findings indicate that \u3e10% W’ depletion is necessary to evoke different metabolic responses to HIIT

A Comparison of Pairs Figure Skaters in Repeated Jumps

Trends in pairs figure skating have shown that increasingly difficult jumps have become an essential aspect of high-level performance, especially in the latter part of a competitive program. We compared a repeated jump power index in a 60 s repeated jump test to determine the relationship of repeated jump test to competitive rank and to measure 2D hip, knee, and ankle angles and angular velocities at 0, 20, 40, and 60 s. Eighteen National Team Pairs Figure Skaters performed a 60 s repeated jump test on a large switch-mat with timing of flight and ground durations and digital video recording. Each 60-s period was divided into 6, 10-s intervals, with power indexes (W/kg) calculated for each 10-s interval. Power index by 10-s interval repeated measures ANOVAs (RMANOVA) showed that males exceeded females at all intervals, and the highest power index interval was during 10 to 20 s for both sexes. RMANOVAs of angles and angular velocities showed main effects for time only. Power index and jumping techniques among figure skaters showed rapid and steady declines over the test duration. Power index can predict approximately 50% of competitive rank variance, and sex differences in jumping technique were rare

Accreditation council for graduate medical education (ACGME) annual anesthesiology residency and fellowship program review: a "report card" model for continuous improvement

<p>Abstract</p> <p>Background</p> <p>The Accreditation Council for Graduate Medical Education (ACGME) requires an annual evaluation of all ACGME-accredited residency and fellowship programs to assess program quality. The results of this evaluation must be used to improve the program. This manuscript describes a metric to be used in conducting ACGME-mandated annual program review of ACGME-accredited anesthesiology residencies and fellowships.</p> <p>Methods</p> <p>A variety of metrics to assess anesthesiology residency and fellowship programs are identified by the authors through literature review and considered for use in constructing a program "report card."</p> <p>Results</p> <p>Metrics used to assess program quality include success in achieving American Board of Anesthesiology (ABA) certification, performance on the annual ABA/American Society of Anesthesiology In-Training Examination, performance on mock oral ABA certification examinations, trainee scholarly activities (publications and presentations), accreditation site visit and internal review results, ACGME and alumni survey results, National Resident Matching Program (NRMP) results, exit interview feedback, diversity data and extensive program/rotation/faculty/curriculum evaluations by trainees and faculty. The results are used to construct a "report card" that provides a high-level review of program performance and can be used in a continuous quality improvement process.</p> <p>Conclusions</p> <p>An annual program review is required to assess all ACGME-accredited residency and fellowship programs to monitor and improve program quality. We describe an annual review process based on metrics that can be used to focus attention on areas for improvement and track program performance year-to-year. A "report card" format is described as a high-level tool to track educational outcomes.</p

Spatting restricts ankle motion more effectively than taping during exercise

Ankle injuries, via plantarflexion (PF) and inversion, are commonplace today. To reduce ankle injuries, restrictive appliances such as taping and bracing have been employed. These appliances, however, have the disadvantage of potentially loosening considerably with mild activity. Spatting—applying tape over the shoe and sock—has been suggested as a viable alternative, yet its efficacy has not been researched widely. We examined the effects of taping or spatting the ankles on 17 men (age = 20.7 ± 2.1 years; height = 185.7 ± 5.7 cm; mass = 93.6 ± 16.2 kg) before, during, and after 60 minutes of exercise involving multi-directional activity. Active range of motion (ROM) for PF and inversion was measured via goniometry for each subject\u27s dominant leg to establish baseline values. ROM was measured after the appliances were applied, then following a five-minute warm-up period, and after each of three, 20-minute exercise periods. The subjects also completed a 5-item, 5-point Likert-type scale survey regarding their perceptions of each ankle appliance with respect to comfort, effectiveness, and protective ability. Separate, two-way ANOVAs with repeated measures were used to assess differences in PF and inversion ROM relative to time. A series of Wilcoxon tests were used to assess the Likert-type scale survey. In comparison to spatting, taping loosened by ~5° for PF at 40 minutes and by ~3° for inversion at 20 minutes (both significant interactions, p \u3c 0.01). Thus indicating that spatting is more restrictive than taping after 20 minutes of exercise. Interestingly, taping was perceived as more comfortable than spatting (Z = 2.03, p = 0.04); nonetheless, the perceived protection along with the perceived ability to move before, during, and after exercise was rated similarly between the appliances (p \u3e 0.05). Despite an advantage of restricting PF and inversion during exercise with spatting, it is not known if the loss of tape-skin contact underscores the potential benefits associated with the neuromuscular reactivity that have been reported with taping. Additional research is needed to clarify this issue

Reply to Simon and Reed: Independent and Converging Results Rule Out Historic Disturbance and Confirm Age Constraints for Barrier Canyon Rock Art

We welcome this further discussion of our results on the age of the Great Gallery rock art in the Canyonlands of Utah. The comment by Simon and Reed (1) focuses on just one of the three components of our study (2), which is presented in greater technical detail in ref. 3 and is surely our best-constrained and least-surprising result: the dating of a rock-fall that removed some of the art and thus provides a minimum age. Simon and Reed (1) point out that the Great Gallery panel is not pristine and relate the sordid human history of visitation and possible disturbance to the site. Indeed, being aware of this during our research, one of our initial hypotheses was that the rock fall may be historic. Despite the possibility of recent disturbance to some of the talus boulders, our results document that the rock fall occurred ∼900 y ago, and for the boulder we sampled a scenario of historic disturbance and exposure such as postulated by Simon and Reed (1) can be ruled out

Age of Barrier Canyon-style rock art constrained by cross-cutting relations and luminescence dating techniques

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial chronostratigraphy constrains the burial and exhumation of the alcove containing the panel, and limits are also set by our related research dating both a rockfall that removed some figures and the rock’s exposure duration before that time. Results provide a maximum possible age, a minimum age, and an exposure time window for the creation of the Great Gallery panel, respectively. The only prior hypothesis not disproven is a late Archaic origin for BCS rock art, although our age result of A.D. ∼1–1100 coincides better with the transition to and rise of the subsequent Fremont culture. This chronology is for the type locality only, and variability in the age of other sites is likely. Nevertheless, results suggest that BCS rock art represents an artistic tradition that spanned cultures and the transition from foraging to farming in the region. Archaeology is focused upon material records, contextualized in time. Rock art is a record with the potential to provide unique insight into the dynamics and evolution of culture, but it generally lacks stratigraphic or chronologic context. Interpretation of the origin and meaning of rock art is indirect at best, or simply speculative. In the case of some pictographs, pigments may include or have enough accessory carbon for accelerator mass spectrometry (AMS) radiocarbon dating (1⇓⇓–4). In other special situations, such as caves, minimum age constraints have been obtained by various techniques of dating material that overlies or entombs rock art (5⇓–7). However, most rock art remains undatable and researchers rely upon stylistic comparison and indirect associations with artifacts at nearby sites (8, 9). The case in point for this study is arguably the most compelling and debated rock art in the United States—the Barrier Canyon style (BCS) of the Colorado Plateau. Previous attempts to derive an absolute chronology have failed and its age remains unknown, with widely ranging hypotheses that have remained untested until now. The continued development of dating techniques offers new possibilities for hypothesis testing. The optically stimulated luminescence (OSL) signals from mineral grains make it possible to date the deposition of most sediment that is exposed to a few seconds of full sunlight before burial, and its use in the earth and cultural sciences has greatly increased (10, 11). Among the latest applications of OSL are techniques dating the outer surfaces of rock clasts that have become shielded from light, including those with archaeological context (12⇓⇓–15). Recent work has furthermore used the “bleaching” profile of decreasing luminescence signal toward the surface of rock to estimate exposure time to sunlight (16, 17). Using these dating tools, we can constrain the age of rock art and gain new insight into past cultures and landscapes. Here, we synthesize results from three approaches to dating the type section of BCS art, the Great Gallery in Canyonlands National Park of southeastern Utah. Through dating the full alluvial stratigraphy and a rockfall event that both have incontrovertible cross-cutting relations with the rock art, and then by determining the exposure duration of a painted rock surface, we greatly narrow the window of time when the rock art was created. These approaches do not require direct sampling of rock art and have strong potential for application to other archaeological and surface processes research. Although our results are only for the type section of BCS art, and chronological variability should be expected for the style across the region, they suggest that BCS art coincides with the transition to agriculture in the northern Colorado Plateau and may not have been limited to a specific archaeological culture