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51.
Research suggests that undergraduate students learn more from lab experiences that involve longer-term projects. We have developed a one-semester laboratory sequence aimed at sophomore-level undergraduates. In designing this curriculum, we focused on several educational objectives: 1) giving students a feel for the scientific research process, 2) introducing them to commonly used lab techniques, and 3) building skills in both data analysis and scientific writing. Over the course of the semester, students carry out two project-based lab experiences and write two substantial lab reports modeled on primary literature. Student assessment data indicate that this lab curriculum achieved these objectives. This article describes the first of these projects, which uses the biflagellate alga Chlamydomonas reinhardtii to introduce students to the study of flagellar motility, protein synthesis, microtubule polymerization, organelle assembly, and protein isolation and characterization.  相似文献   
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The relationship between preschool children's peer competency and the exchange of reciprocal negative affect displays during physical play with parents was examined. Teacher ratings of children's peer competency were obtained from children's preschools. Parents and children (41 families) were observed during a physical play paradigm called "the hand game" which permitted physically stimulating play, yet which also permitted clear recording of participants' facial expressions. Interactions were coded second by second for 8 min using a system of 12 mutually exclusive and exhaustive codes to categorize the affect displayed by participants. Fathers who typically responded to their children's negative affect displays with negative affect of their own had children who shared less, were more aggressive, and avoided others. Implications of the findings for theories of family-peer relationships are discussed.  相似文献   
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The Microsoft Xbox One Kinect? (Kinect V2) contains a depth camera that can be used to manually identify anatomical landmark positions in three-dimensions independent of the standard skeletal tracking, and therefore has potential for low-cost, time-efficient three-dimensional movement analysis (3DMA). This study examined inter-session reliability and concurrent validity of the Kinect V2 for the assessment of coronal and sagittal plane kinematics for the trunk, hip and knee during single leg squats (SLS) and drop vertical jumps (DVJ). Thirty young, healthy participants (age = 23 ± 5yrs, male/female = 15/15) performed a SLS and DVJ protocol that was recorded concurrently by the Kinect V2 and 3DMA during two sessions, one week apart. The Kinect V2 demonstrated good to excellent reliability for all SLS and DVJ variables (ICC ≥ 0.73). Concurrent validity ranged from poor to excellent (ICC = 0.02 to 0.98) during the SLS task, although trunk, hip and knee flexion and two-dimensional measures of knee abduction and frontal plane projection angle all demonstrated good to excellent validity (ICC ≥ 0.80). Concurrent validity for the DVJ task was typically worse, with only two variables exceeding ICC = 0.75 (trunk and hip flexion). These findings indicate that the Kinect V2 may have potential for large-scale screening for ACL injury risk, however future prospective research is required.  相似文献   
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Single-case research designs are useful for learning disability researchers interested in refining novel interventions (e.g., new mathematics intervention) before scaling, small n populations (e.g., students with comorbid learning and emotional and behavioral disabilities), and testing unique conditions (e.g., remote locales). Much attention has been devoted to developing research quality standards, which is essential for replication and implementation fidelity; however, little is known about the reporting quality of single-case design studies. To gain insight into the quality of learning disability single-case research design study reporting, we analyzed 72 articles published between 2010 and 2021 in six learning disability-focused journals using the Single-Case Reporting Guideline In BEhavioral interventions (SCRIBE) standards. Findings suggest that reporting quality has remained stagnant, and none of the studies reviewed met all of the reporting standards. Alignment with standards ranged from 33% to 77%. Implications for researchers and practitioners are discussed.  相似文献   
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This article employs autoethnographic reflections to contribute towards debates concerning film-induced tourism by analysing the officially endorsed Doctor Who Experience Walking Tour around filming locations from the BBC series in Cardiff Bay, Wales. Approaching this tour as an example of paratextuality, the article pursues two arguments. First, it reflects upon the attempts used within the tour for encouraging connection between participants and the locations visited from the perspective of immersion. However, noting preceding positions, it is recognized that the tour constructs forms of imaginative immersion. The terms symbolic and cued immersion are subsequently introduced to consider the strategies that the tour employs to position fans and engage them with its frequently quotidian spaces. Second, the article explores the links between the tour’s immersive strategies and its institutional context, arguing that these assist in reinforcing core brand values regarding BBC Worldwide.  相似文献   
59.
Biodeterioration of Incralac used for the protection of bronze monuments   总被引:2,自引:0,他引:2  
Outdoor bronze sculptures are highly susceptible to corrosion in many environments and organic coatings are widely used for their protection. The purpose of this study was to determine the susceptibility of the commonly used coating Incralac to biodeterioration by microorganisms. A yeast was isolated from a bronze statue treated with Incralac and its ability to degrade Incralac was determined using growth curves, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The organism grew slowly on Incralac in liquid culture, but SEM images demonstrated its ability to adhere to Incralac coated metal. Additionally, the yeast caused a rapid drop in the low frequency impedance of Incralac coated metal that was not observed under sterile conditions, indicating that the organism accelerated deterioration of the coating. The potential for microbial growth to accelerate deterioration of Incralac should be considered when developing a maintenance strategy for the protection of outdoor metal monuments.  相似文献   
60.
Abstract

This study investigated the influence of the regression model and initial intensity during an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and performance in elite-standard runners. Twenty-three well-trained runners completed a discontinuous incremental running test on a treadmill. Speed started at 9 km · h?1 and increased by 1.5 km · h?1 every 4 min until exhaustion, with a minute of recovery for blood collection. Lactate–speed data were fitted by exponential and polynomial models. The lactate threshold was determined for both models, using all the co-ordinates, excluding the first and excluding the first and second points. The exponential lactate threshold was greater than the polynomial equivalent in any co-ordinate condition (P < 0.001). For both models, the lactate threshold was lower when all co-ordinates were used than when the first and the first and second points were excluded (P < 0.001). 10-km race pace was correlated with both the exponential and polynomial lactate thresholds for all the co-ordinate conditions (r ≥ 0.75, < 0.001 and r ≥ 0.56, P < 0.05, respectively). The results suggest that the exponential lactate threshold should be used instead of the polynomial equivalent since it is more strongly associated with performance and is independent of the initial intensity of the test.  相似文献   
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