Fibronectin and Cyclic Strain Improve Cardiac Progenitor Cell Regenerative Potential In Vitro.

Cardiac progenitor cells (CPCs) have rapidly advanced to clinical trials, yet little is known regarding their interaction with the microenvironment. Signaling cues present in the microenvironment change with development and disease. This work aims to assess the influence of two distinct signaling moieties on CPCs: cyclic biaxial strain and extracellular matrix. We evaluate four endpoints for improving CPC therapy: paracrine signaling, proliferation, connexin43 expression, and alignment. Vascular endothelial growth factor A (about 900 pg/mL) was secreted by CPCs cultured on fibronectin and collagen I. The application of mechanical strain increased vascular endothelial growth factor A secretion 2-4-fold for CPCs cultured on poly-L-lysine, laminin, or a naturally derived cardiac extracellular matrix. CPC proliferation was at least 25% higher on fibronectin than that on other matrices, especially for lower strain magnitudes. At 5% strain, connexin43 expression was highest on fibronectin. With increasing strain magnitude, connexin43 expression decreased by as much as 60% in CPCs cultured on collagen I and a naturally derived cardiac extracellular matrix. Cyclic mechanical strain induced the strongest CPC alignment when cultured on fibronectin or collagen I. This study demonstrates that culturing CPCs on fibronectin with 5% strain magnitude is optimal for their vascular endothelial growth factor A secretion, proliferation, connexin43 expression, and alignment

Implications for Practice and Research

One of the advantages of doing research with so many dependent variables is that you get a more complete picture of the effects of instruction and the interrelationships among variables. One of the disadvantages is that it is more difficult to communicate those results. The studies reported in this monograph (French, Werner, Rink, Taylor, & Hussey, 1996; French, Werner, Taylor, Hussey, & Jones, 1996) are important because the results are consistent across both experiments with different teachers, with different students, and at different times. They are important because, unlike much of the research in this field, all of the students in the experimental groups were significantly better as a result of instruction on all the key dependent measures. We think these studies will add to the knowledge base in pedagogy and on how to do research in this area. We present them, not as the last word on approaches to teaching and researching games and sport, but to initiate dialogue about how to teach games and sports to children and youth in our schools and how to investigate how to teach games and sports in our schools. We have two objectives for this article. The first is to review the findings of these two studies and draw implications of the results for practice and the second is to use what we have learned to draw implications for future research

The Effects of a 3-Week Unit of Tactical, Skill, or Combined Tactical and Skill Instruction on Badminton Performance of Ninth-Grade Students

Interest in alternative models for games/sport instruction has increased in recent years. Recent research has compared tactical approaches to games/sport instruction with more skill-oriented approaches (Gabriele & Maxwell, 1995; Griffin, Olsin, & Mitchell, 1995; McPherson & French, 1991; Turner & Martinek, 1992, 1995b). Most of the research in this area to date has focused on student performance outcomes (knowledge, skill, game play performance) that result from different skill and tactical approaches to instruction and learning

The Influence of Content Development on the Effectiveness of Instruction

The purpose of this study was to investigate the effect on student learning of different ways of structuring student practice of complex motor skills. Previous research indicated that students who practiced the volleyball set and serve with a four-step progression learned more than students who practiced only the final test for the same number of practice trials; the effect of motivation and practice focused on specific learning cues was unclear. The present study investigated the specific role of progression, refinement, and motivation in learning the volleyball set and serve. Ninth-grade students were randomly assigned to one of five groups: (a) control, (b) final-test practice with refinement tasks after every five trials, (c) final-test practice with motivational feedback only, (d) four-step progression, and (e) four-step progression with refinement after every five trials. All experimental groups were pre-tested and posttested using the AAHPERD volleyball test for the set and server and practiced each skill 10 times a day for 6 days. The results supported the positive effect of providing students with a progression and the need for refinement tasks for parts of the progression

The Effects of Practice Progressions on Learning Two Volleyball Skills

The purpose was to compare the effectiveness of practice progressions on learning the volleyball serve and overhead set. Ninth-grade students were randomly assigned to three groups. Each group practiced the volleyball serve and set for 60 trials over 6 days. The progression group practiced four levels of difficulty of the set and serve. The criterion group began practice at the beginning level of difficulty and had to achieve an 80% success rate before practicing at a more advanced level. The third group practiced the AAHPERD volleyball skill tests for the serve and set for all 60 trials. At the end of practice, all subjects were posttested using these AAHPERD tests. The results indicated the progression and criterion groups had higher posttest scores than the third group. Profiles of the success rates across acquisition for each group showed that students in the third group and low-skilled students in the progression and criterion groups did not improve during practice. Students with some initial skill in the progression and criterion groups exhibited high success rates for acquisition and improvement. These results indicate that sequencing practice in progressive levels of difficulty enhances retention when task difficulty is appropriate for the learner. However, no condition was effective when task difficulty was inappropriate for the learner

A Comparison of Pedagogical Knowledge Structures of Preservice Students and Teacher Educators in Two Institutions

Understanding how the knowledge structures of preservice teachers develop as expertise is acquired would seem to be an important aspect of teacher preparation. The purpose of this study was to compare the pedagogical knowledge structures about effective teaching of preservice teachers and teacher educators in the professional preparation programs of two different institutions. Two groups of preservice teachers at two different points in their preparation program at each of the two institutions were asked to complete a concept map (Roehler et al., 1987) about effective teaching. One group completed the concept map just after the first teaching methods course, and the other group completed the map just prior to student teaching. These data were compared with concept maps of teacher educators at each institution. Quantitative and qualitative data revealed differences between the groups of preservice teachers and between the preservice teachers and the teacher educators

Perioperative Outcomes of Patients with Bleeding Disorders Undergoing Major Surgery at an Academic Hemophilia Treatment Center

Persons with bleeding disorders (PwBD) are at high risk for bleeding with invasive procedures. However, the risk of bleeding in PwBD undergoing major surgery and outcomes of patients managed perioperatively at a hemophilia treatment center (HTC) are not well described. We performed a retrospective review of surgical outcomes among PwBD undergoing major surgery between January 1st, 2017 and December 31st, 2019 at the Cardeza Foundation Hemophilia and Thrombosis Center in Philadelphia, PA. The primary outcome was postoperative bleeding, assessed according to the ISTH-SSC\u27s 2010 definition. Secondary outcomes included use of unplanned postoperative hemostatic therapy, LOS, and 30-day readmission rate. Results were compared to non-PwBD population from a surgical database, matched for surgery, age, and sex. During the study period, 50 PwBD underwent 63 major surgeries. The most common diagnoses were VWD (64%) and hemophilia A (20.0%). The most common surgical procedure category was orthopedic (33.3%), predominantly arthroplasties. Postoperatively,4.8% of procedures were complicated by major bleeding and 1.6% by non-major bleeding. The mean LOS was 1.65 days, and 30-day readmission rate was 1.6%. In comparison to matched, non-PwBD patients in a national surgical database undergoing the same procedures, study patients had a similar rate of bleeding complications per procedure (5.0% vs 1.04

Invasive frogs show persistent physiological differences to elevation and acclimate to colder temperatures

The coqui frog (Eleutherodactylus coqui) was introduced to the island of Hawai’i in the 1980s and has spread across much of the island. Concern remains that this frog will continue to expand its range and invade higher elevation habitats where much of the island’s endemic species are found. We determined whether coqui thermal tolerance and physiology change along Hawai’i’s elevational gradients. We measured physiological responses using a short-term experiment to determine baseline tolerance and physiology by elevation, and a long-term experiment to determine the coqui’s ability to acclimate to different temperatures. We collected frogs from low, medium, and high elevations. After both the short and long-term experiments, we measured critical thermal minimum (CTmin), blood glucose, oxidative stress, and corticosterone levels. CTmin was lower in high elevation frogs than low elevation frogs after the short acclimation experiment, signifying that they acclimate to local conditions. After the extended acclimation, CTmin was lower in frogs acclimated to cold temperatures compared to warm-acclimated frogs and no longer varied by elevation. Blood glucose levels were positively correlated with elevation even after the extended acclimation, suggesting glucose may also be related to lower temperatures. Oxidative stress was higher in females than males, and corticosterone was not significantly related to any predictor variables. The extended acclimation experiment showed that coquis can adjust their thermal tolerance to different temperatures over a 3-week period, suggesting the expansion of coqui into higher elevation habitats may still be possible, and they may not be as restricted by cold temperatures as previously thought

Evaluating the two-source energy balance model using local thermal and surface flux observations in a strongly advective irrigated agricultural area

Application and validation of many thermal remote sensing-based energy balance models involve the use of local meteorological inputs of incoming solar radiation, wind speed and air temperature as well as accurate land surface temperature (LST), vegetation cover and surface flux measurements. For operational applications at large scales, such local information is not routinely available. In addition, the uncertainty in LST estimates can be several degrees due to sensor calibration issues, atmospheric effects and spatial variations in surface emissivity. Time differencing techniques using multi-temporal thermal remote sensing observations have been developed to reduce errors associated with deriving the surface- air temperature gradient, particularly in complex landscapes. The Dual-Temperature-Difference (DTD) method addresses these issues by utilizing the Two-Source Energy Balance (TSEB) model of Norman et al. (1995) [1], and is a relatively simple scheme requiring meteorological input from standard synoptic weather station networks or mesoscale modeling. A comparison of the TSEB and DTD schemes is performed using LST and flux observations from eddy covariance (EC) flux towers and large weighing lysimeters (LYs) in irrigated cotton fields collected during BEAREX08, a large-scale field experiment conducted in the semi-arid climate of the Texas High Plains as described by Evett et al. (2012) [2]. Model output of the energy fluxes (i.e., net radiation, soil heat flux, sensible and latent heat flux) generated with DTD and TSEB using local and remote meteorological observations are compared with EC and LY observations. The DTD method is found to be significantly more robust in flux estimation compared to the TSEB using the remote meteorological observations. However, discrepancies between model and measured fluxes are also found to be significantly affected by the local inputs of LST and vegetation cover and the representativeness of the remote sensing observations with the local flux measurement footprint

Neurodevelopmental outcomes at 7 years’ corrected age in preterm infants who were fed high-dose docosahexaenoic acid to term equivalent: a follow-up of a randomised controlled trial

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work noncommercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http:// creativecommons.org/licenses/by-nc/4.0/OBJECTIVE: To determine if improvements in cognitive outcome detected at 18 months' corrected age (CA) in infants born <33 weeks' gestation receiving a high-docosahexaenoic acid (DHA) compared with standard-DHA diet were sustained in early childhood. DESIGN: Follow-up of a multicentre randomised controlled trial. Randomisation was stratified for sex, birth weight (<1250 vs ≥1250 g) and hospital. SETTING: Five Australian tertiary hospitals from 2008 to 2013. PARTICIPANTS: 626 of the 657 participants randomised between 2001 and 2005 were eligible to participate. INTERVENTIONS: High-DHA (≈1% total fatty acids) enteral feeds compared with standard-DHA (≈0.3% total fatty acids) from age 2-4 days until term CA. PRIMARY OUTCOME: Full Scale IQ of the Wechsler Abbreviated Scale of Intelligence (WASI) at 7 years CA. Prespecified subgroup analyses based on the randomisation strata (sex, birth weight) were conducted. RESULTS: 604 (92% of the 657 originally randomised) consented to participate (291 high-DHA, 313 standard-DHA). To address missing data in the 604 consenting participants (22 for primary outcome), multiple imputation was performed. The Full Scale IQ was not significantly different between groups (high-DHA 98.3, SD 14.0, standard-DHA 98.5, SD 14.9; mean difference adjusted for sex, birthweight strata and hospital -0.3, 95% CI -2.9 to 2.2; p=0.79). There were no significant differences in any secondary outcomes. In prespecified subgroup analyses, there was a significant sex by treatment interaction on measures of parent-reported executive function and behaviour. Scores were within the normal range but girls receiving the high-DHA diet scored significantly higher (poorer outcome) compared with girls receiving the standard-DHA diet. CONCLUSIONS: Supplementing the diets of preterm infants with a DHA dose of approximately 1% total fatty acids from days 2-4 until term CA showed no evidence of benefit at 7 years' CA. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry: ACTRN12606000327583