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1.
BackgroundResearch on achievement goal orientations in sport has typically relied on the use of variable-centered approaches that tend to overlook population heterogeneity. In this study, we used a person-centered approach to identify subgroups of competitive tennis players according to unique combinations of achievement goal orientations and tested for subgroup differences in motivation and mental toughness.MethodsA sample of 323 competitive tennis athletes (69.35% male) between 15 and 25 years of age (17.60 ± 2.40 years, mean ± SD) completed the 3 × 2 Achievement Goal Questionnaire for Sport, Sport Motivation Scale II, and Mental Toughness Index. Latent profile analysis was used to identify unique combinations of achievement goal orientations. Comparisons between latent subgroups on autonomous motivation, controlled motivation, and mental toughness were performed using analysis of variance.ResultsLatent profile analysis supported 3 distinct patterns of achievement goal profiles that were primarily distinguishable based on valence of competence (i.e., approach vs. avoidance). Analyses of variance indicated that athletes who were classified into subgroups that endorsed approach types of goals (regardless of the types of avoidance goals they endorsed) reported higher levels of autonomous motivation and mental toughness.ConclusionResults indicated that athletes tend to pursue a number of achievement goals collectively rather than in isolation. Although approach goals are more commonly linked to adaptive psychological functioning and positive outcomes, avoidance goals may also be associated with desirable psychological characteristics if they are pursued in conjunction with approach types of achievement goals.  相似文献   
2.
ABSTRACT

This study examined how work–family conflict (WFC) is associated with mechanisms of relational turbulence, conflict tactics, and marital satisfaction. Six hundred and thirty-three married workers completed an online survey. Family interference with work and spouses’ work interfering with one’s family predicted greater relational uncertainty and interference from partners, whereas one’s own work interfering with family did not predict these mechanisms of turbulence. All three sources of relational uncertainty, and interference from partners, predicted increased avoidance and distributive tactic use. Facilitation from partners predicted increased use of integrative tactics. Finally, relational uncertainty, interference from partners, and distributive conflict tactics partially mediated the associations of WFC with marital satisfaction.  相似文献   
3.
The aim of the study was to determine if sex differences exist in the key elbow and wrist joint injury risk factors during different cartwheel (CW) and round-off (RO) techniques performed by young male and female artistic gymnasts. Sixteen active young gymnasts (8 males and 8 females) performed 30 successful trials of CW and RO with three different hand positions (parallel (10), T-shape (10) and reverse (10)). Synchronised kinematic and kinetic data were collected for each trial. Two-way repeated measures ANOVA (3 × 2, technique × sex) and effect-sizes (ES) were used for statistical analysis. In conclusion, female gymnasts exhibited greater normalised peak vertical ground reaction forces (VGRF), elbow and wrist compression forces and elbow internal adduction moments during CW and RO skills compared with male gymnasts. In both sexes, the parallel and reverse techniques increased peak VGRF, elbow and wrist compression forces and the elbow internal adduction moment. Increased elbow flexion resulted in decreased peak VGRF, elbow compression forces and elbow internal adduction moment. Injury risk factors including elbow extension and internal adduction moment with axial compression force suggest that a CW and RO in reverse and parallel techniques can be hazardous especially for young female gymnasts.  相似文献   
4.
The evidence base for school-based consultation practice and training is limited by a small number of studies, possibly due to unique challenges in researching consultation. For example, there are myriad variables to measure and idiosyncratic cultural and contextual factors to account for when investigating what works, for whom, and in what circumstances. Survey methodology offers one means for conducting consultation research. This article proposes a process for rigorous survey research in school-based consultation training and practice, which addresses some potential concerns regarding survey research. Specifically, issues of survey development, survey validation, sampling, and data collection are addressed. These processes are illustrated through the design and administration of an online survey of 262 early career school psychologists; preliminary data analyses suggested strong scale reliability, minimal item response bias, and population representativeness. Recommendations for future consultation survey research are provided.  相似文献   
5.

This response to Lee and Hannafin’s A design framework for enhancing engagement in student-centered learning: own it, learn it, and share it (OLSit) (Lee and Hannafin, Educational Technology Research and Development 64:707–734, 2016) discusses its helpful design guidelines from a practitioner’s perspective. OLSit provides a blueprint for chance-taking with student-centered learning. Here, I apply this blueprint to a flexible assignment colleagues and I designed to promote intrinsic motivation and engagement, called Pink Time (PT), which asks students to “skip class, do whatever you want, and grade yourself.” Together, OLSit and PT are well suited for this moment of disruption and pivot to remote learning. Students’ stereotypes about what is “valid” in the classroom may be important limitations. But iterative and effective communication can shape students’ perceptions and scaffold their efforts. In the future, scholars and practitioners should consider how grades undermine online SCL strategies like OLSit and PT.

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6.
The world-wide use of digital storage and communications devices is increasing the need to make texts available in multiple languages. In this article we explore the possibility of storing a compressed form of a translated version of a text, taking advantage of the availability of the original text. The original text provides some of the semantic content of the text that is to be compressed, and therefore makes it possible for compression to be more efficient than if that information were not available. We begin with an experiment to evaluate the information content of a text when a parallel translation is available. This is achieved by having human subjects guess texts letter by letter, with and without a parallel translation. The perceived information content of a text can be determined from the way subjects make their guesses. The design and results of this experiment are described. The main conclusion is that while the text is considerably more predictable with the aid of a parallel translation, there is a surprising amount of information introduced by the translation. Insights obtained from this experiment are then applied in the design of a mechanical system for compressing parallel texts. The system stores one translation of a text intact, and then compresses further translations of the text with the aid of the original. The method described is able to compress texts significantly better than is possible without the aid of a parallel text. Aspects of the design are also applicable to future compressors that might take advantage of the semantic content of a text to obtain better compression.  相似文献   
7.
Although the inventions embodied in the Internet originated in a diverse set of industrial economies, the US was consistently the source of critical innovations and an early adopter of new applications. Why did other nations, including several that made important inventive contributions to the Internet, not play a larger role in its development, particularly in the creation of new business organizations, governance institutions, and applications? We argue that the role of the US “national innovation system” in the creation of the Internet echoes several key themes of US technological development before 1940. The presence of a large domestic market, a set of antitrust and regulatory policies that weakened the power of incumbent telecommunications firms, and a diverse private/public research community that was willing to work with both domestic and foreign inventions were important preconditions for US leadership in computer networking innovation.  相似文献   
8.
Educational technology research and development - Moodle is widely used in higher education institutions in this digital age. With the growing popularity of Moodle use in education, this study...  相似文献   
9.
Abstract

A key element contributing to deteriorating exercise capacity during physically demanding sport appears to be reduced carbohydrate availability coupled with an inability to effectively utilize alternative lipid fuel sources. Paradoxically, cognitive and physical decline associated with glycogen depletion occurs in the presence of an over-abundance of fuel stored as body fat that the athlete is apparently unable to access effectively. Current fuelling tactics that emphasize high-carbohydrate intakes before and during exercise inhibit fat utilization. The most efficient approach to accelerate the body’s ability to oxidize fat is to lower dietary carbohydrate intake to a level that results in nutritional ketosis (i.e., circulating ketone levels >0.5 mmol/L) while increasing fat intake for a period of several weeks. The coordinated set of metabolic adaptations that ensures proper interorgan fuel supply in the face of low-carbohydrate availability is referred to as keto-adaptation. Beyond simply providing a stable source of fuel for the brain, the major circulating ketone body, beta-hydroxybutyrate, has recently been shown to act as a signalling molecule capable of altering gene expression, eliciting complementary effects of keto-adaptation that could extend human physical and mental performance beyond current expectation. In this paper, we review these new findings and propose that the shift to fatty acids and ketones as primary fuels when dietary carbohydrate is restricted could be of benefit for some athletes.  相似文献   
10.
This article examines the validity of the Undergraduate Research Student Self-Assessment (URSSA), a survey used to evaluate undergraduate research (UR) programs. The underlying structure of the survey was assessed with confirmatory factor analysis; also examined were correlations between different average scores, score reliability, and matches between numerical and textual item responses. The study found that four components of the survey represent separate but related constructs for cognitive skills and affective learning gains derived from the UR experience. Average scores from item blocks formed reliable but moderate to highly correlated composite measures. Additionally, some questions about student learning gains (meant to assess individual learning) correlated to ratings of satisfaction with external aspects of the research experience. The pattern of correlation among individual items suggests that items asking students to rate external aspects of their environment were more like satisfaction ratings than items that directly ask about student skills attainment. Finally, survey items asking about student aspirations to attend graduate school in science reflected inflated estimates of the proportions of students who had actually decided on graduate education after their UR experiences. Recommendations for revisions to the survey include clarified item wording and increasing discrimination between item blocks through reorganization.Undergraduate research (UR) experiences have long been an important component of science education at universities and colleges but have received greater attention in recent years, as they have been identified as important ways to strengthen preparation for advanced study and work in the science fields, especially among students from underrepresented minority groups (Tsui, 2007 ; Kuh, 2008 ). UR internships provide students with the opportunity to conduct authentic research in laboratories with scientist mentors, as students help design projects, gather and analyze data, and write up and present findings (Laursen et al., 2010 ). The promised benefits of UR experiences include both increased skills and greater familiarity with how science is practiced (Russell et al., 2007 ). While students learn the basics of scientific methods and laboratory skills, they are also exposed to the culture and norms of science (Carlone and Johnson, 2007 ; Hunter et al., 2007 ; Lopatto, 2010 ). Students learn about the day-to-day world of practicing science and are introduced to how scientists design studies, collect and analyze data, and communicate their research. After participating in UR, students may make more informed decisions about their future, and some may be more likely to decide to pursue graduate education in science, technology, engineering, and mathematics (STEM) disciplines (Bauer and Bennett, 2003 ; Russell et al., 2007 ; Eagan et al. 2013 ).While UR experiences potentially have many benefits for undergraduate students, assessing these benefits is challenging (Laursen, 2015 ). Large-scale research-based evaluation of the effects of UR is limited by a range of methodological problems (Eagan et al., 2013 ). True experimental studies are almost impossible to implement, since random assignment of students into UR programs is both logistically and ethically impractical, while many simple comparisons between UR and non-UR groups of students suffer from noncomparable groups and limited generalizability (Maton and Hrabowski, 2004 ). Survey studies often rely on poorly developed measures and use nonrepresentative samples, and large-scale survey research usually requires complex statistical models to control for student self-selection into UR programs (Eagan et al., 2013 ). For smaller-scale program evaluation, evaluators also encounter a number of measurement problems. Because of the wide range of disciplines, research topics, and methods, common standardized tests assessing laboratory skills and understandings across these disciplines are difficult to find. While faculty at individual sites may directly assess products, presentations, and behavior using authentic assessments such as portfolios, rubrics, and performance assessments, these assessments can be time-consuming and not easily comparable with similar efforts at other laboratories (Stokking et al., 2004 ; Kuh et al., 2014 ). Additionally, the affective outcomes of UR are not readily tapped by direct academic assessment, as many of the benefits found for students in UR, such as motivation, enculturation, and self-efficacy, are not measured by tests or other assessments (Carlone and Johnson, 2007 ). Other instruments for assessing UR outcomes, such as Lopatto’s SURE (Lopatto, 2010 ), focus on these affective outcomes rather than direct assessments of skills and cognitive gains.The size of most UR programs also makes assessment difficult. Research Experiences for Undergraduates (REUs), one mechanism by which UR programs may be organized within an institution, are funded by the National Science Foundation (NSF), but unlike many other educational programs at NSF (e.g., TUES) that require fully funded evaluations with multiple sources of evidence (Frechtling, 2010 ), REUs are generally so small that they cannot typically support this type of evaluation unless multiple programs pool their resources to provide adequate assessment. Informal UR experiences, offered to students by individual faculty within their own laboratories, are often more common but are typically not coordinated across departments or institutions or accountable to a central office or agency for assessment. Partly toward this end, the Undergraduate Research Student Self-Assessment (URSSA) was developed as a common assessment instrument that can be compared across multiple UR sites within or across institutions. It is meant to be used as one source of assessment information about UR sites and their students.The current research examines the validity of the URSSA in the context of its use as a self-report survey for UR programs and laboratories. Because the survey has been taken by more than 3400 students, we can test some aspects of how the survey is structured and how it functions. Assessing the validity of the URSSA for its intended use is a process of testing hypotheses about how well the survey represents its intended content. This ongoing process (Messick, 1993 ; Kane, 2001 ) involves gathering evidence from a range of sources to learn whether validity claims are supported by evidence and whether the survey results can be used confidently in specific contexts. For the URSSA, our method of inquiry focuses on how the survey is used to assess consortia of REU sites. In this context, survey results are used for quality assurance and comparisons of average ratings over years and as general indicators of program success in encouraging students to pursue graduate science education and scientific careers. Our research questions focus on the meaning and reliability of “core indicators” used to track self-reported learning gains in four areas and the ability of numerical items to capture student aspirations for future plans to attend graduate school in the sciences.  相似文献   
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