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There is an expectation that physical educators will provide games, activities, and interactions that will positively affect student attitudes toward being physically active throughout their lives. Unfortunately, certain pedagogical practices have been employed in physical education (PE) classes that negatively affect attitudes toward physical activity. Of those practices, incorporating student exercise as punishment (EAP) was the focus of this investigation. The purpose of this study was to explore individuals' (i.e., former students in PE) perspectives regarding their experiences of EAP. Findings suggest the use of EAP negatively affected the classroom environment as well as perceptions toward physical educators. Former PE students reported EAP did not teach valuable life lessons, with running and push-ups identified as the most common methods that physical educators used to punish students. Results of this study reveal that EAP may not be an appropriate practice and that physical educators should identify other methods of classroom management to create a more positive learning environment.

Physical education (PE) has the potential to educate students to spend a lifetime in physical activity. An up-and-coming activity that has this potential of lifetime activity is spike ball. Generally, spike ball is played with four players with teams of two. The ball is put into play and the players can move anywhere they want. The objective is to hit the ball into the net so that the opposing team cannot return it. Spike ball presents itself to be an activity for students in high school and col-lege/university. One aspect of increasing activity during spike ball is music being played. Research dealing with music in physical activity settings has found it to enhance endurance and color how people inter-pret fatigue. Thus, the purpose of this study was to examine the effects of music on PA rates (measured via pedometer) of college students as they play spike ball. Generally, it was learned that music had a positive effect on increased amounts of steps taken and time in activity during spike ball play.

Congenic lines that differ in a single defined chromosome segment are useful for the study of complex phenotypes, as they allow isolation of the effect of a particular quantitative trait locus (QTL) from those of the entire genome. We conducted high-resolution QTL mapping of a 9-cM introgression, originating from the wild tomato species Lycopersicon pennellii, in two extremely different genetic and physiological backgrounds. In the \"indeterminate\" glasshouse background we identified only a single QTL ( Brix9-2-5) that affects the total soluble solids of the fruit [mainly sugars, measured in Brix units (B)]. This QTL was previously delimited within the gene for an apoplastic invertase, Lin5, that modulates sugar partitioning to the fruit. Analysis of the effects of the same chromosome segment in \"determinate\", open-field tomatoes, revealed two QTLs, 0.3 cM apart: the fruit-specific Brix9-2-5 that affects B only, and the shoot-specific PW9-2-5, which accounts for an altered growth habit resulting in increases in plant weight, yield, and B. This study highlights the power of the congenic approach for dissecting developmental pathways leading to complex phenotypes.

The incorporation of music in the physical education (PE) environment during physical activity has been shown to be beneficial for participants. Karageorghis et al. (1999) created a conceptual framework focusing on asynchronous music, identifying four factors important to a given piece of music: rhythm response, musicality, cultural impact, and association. The purpose of this study was to investigate the effect of two conditions, with and without the incorporation of music, in the PE environment on student moods in 948 junior high school students (501 males, 447 females). The conditions were measured using the Profile of Mood States (POMS) Short Form. Significant differences were observed in the mean scores of POMS between preintervention (without music) and postintervention (with music) for total mood disturbance, tension, anger, fatigue, depression, and confusion (all p values < 0.0001), as well as significantly higher mean scores for esteem-related affect and vigor (p values < 0.0001). Results from this study, and others, provide an impetus for PE teachers and PE teacher education to incorporate music during games/activities for the purpose of improving student moods and subsequent activity levels.

The purpose of this study was to explore grade-level differences (7th, 8th, and 9th) among junior high school students' perceptions of the effects of participation in physical education (PE) class on individual environmental stress. The role of physical activity as a stress reduction tool has been well documented. However, physical activity as a stressful event in the school and PE environment has been less established, particularly in junior high school students. Study participants comprised 872 junior high school students, 585 males (67%) and 287 females (33%), enrolled in four junior high schools. Stratified by grade, 315 seventh-grade (228 males, 87 females; M = 1.28, SD = 0.448), 281 eighth-grade (204 males, 77 females; M = 1.27, SD = 0.447), and 276 ninth-grade (153 males, 123 females; M = 1.45, SD = 0.498) students responded. By grade level, significant differences (p < 0.05) were reported for five of the 12 scaling questions. In general, seventh graders were more likely to respond they could better handle stress after participating in PE class, to look forward to coming to their PE class, to report lower stress levels before arrival to PE class, and to report lower stress levels after participation in PE class than were eighth and ninth graders. Altogether, follow-up qualitative findings reported three major themes regarding the PE environment and stress. PE acted as a stress mitigation mechanism and an opportunity for social bonding. Qualitative findings also referenced classmates as a negative stress mechanism in the PE environment.

Tomato represents an important source of fiber and nutrients in the human diet and is a central model for the study of fruit biology. To identify components of fruit metabolic composition, here we have phenotyped tomato introgression lines (ILs) containing chromosome segments of a wild species in the genetic background of a cultivated variety. Using this high-diversity population, we identify 889 quantitative fruit metabolic loci and 326 loci that modify yield-associated traits. The mapping analysis indicates that at least 50% of the metabolic loci are associated with quantitative trait loci (QTLs) that modify whole-plant yield-associated traits. We generate a cartographic network based on correlation analysis that reveals whole-plant phenotype associated and independent metabolic associations, including links with metabolites of nutritional and organoleptic importance. The results of our genomic survey illustrate the power of genome-wide metabolic profiling and detailed morphological analysis for uncovering traits with potential for crop breeding.

Objectives: To provide further information regarding physical education (PE) teachers' perceptions of incorporating music in PE lessons and to evaluate the influence of music on the classroom environment using a qualitative approach. Method: Electronic survey interviews were conducted with 26 veteran PE instructors (10 male, 16 female), from 7 states and 24 schools (7 elementary schools, 15 middle schools, 4 high schools). Participant teaching experience ranged from 1 to 25 years. Results: Analyses of interview transcripts revealed four major themes concerning the use of music in the PE environment: (1) classroom management, (2) student learning, (3) class climate, and (4) music as a motivational tool. Two repeating themes within the major theme of classroom management were the assistance of music in starting and stopping class activities. Other classroom environmental factors within the major themes of student learning, class climate, and music as a motivational tool were specific to student focus, the predilection of contemporary music by students in the classroom, and perceived increased motivation in classroom activities by students, respectively. Conclusions: Study findings point to the fact PE teachers find music as a helpful tool to assist in class activities. Incorporated during class activities, music may help to create a positive class climate, serving as a tool to help PE teachers manage students and keep them on task.

Heterosis, or hybrid vigor, is a major genetic force that contributes to world food production. The genetic basis of heterosis is not clear, and the importance of loci with overdominant (ODO) effects is debated. One problem has been the use of whole-genome segregating populations, where interactions often mask the effects of individual loci. To assess the contribution of ODO to heterosis in the absence of epistasis, we carried out quantitative genetic and phenotypic analyses on a population of tomato (Solanum lycopersicum) introgression lines (ILs), which carry single marker-defined chromosome segments from the distantly related wild species Solanum pennellii. The ILs revealed 841 quantitative trait loci (QTL) for 35 diverse traits measured in the field on homozygous and heterozygous plants. ILs showing greater reproductive fitness were characterized by the prevalence of ODO QTL, which were virtually absent for the nonreproductive traits. ODO can result from true ODO due to allelic interactions of a single gene or from pseudoODO that involves linked loci with dominant alleles in repulsion. The fact that we detected dominant and recessive QTL for all phenotypic categories but ODO only for the reproductive traits indicates that pseudoODO due to random linkage is unlikely to explain heterosis in the ILs. Thus, we favor the true ODO model involving a single functional Mendelian locus. We propose that the alliance of ODO QTL with higher reproductive fitness was selected for in evolution and was domesticated by man to improve yields of crop plants.

In nature, genetic variation usually takes the form of a continuous phenotypic range rather than discrete classes. The genetic variation underlying quantitative traits results from the segregation of numerous interacting quantitative trait loci (QTLs), whose expression is modified by the environment. To uncover the molecular basis of this variation, we characterized a QTL (Brix9-2-5) derived from the green-fruited tomato species Lycopersicon pennellii. The wild-species allele increased glucose and fructose contents in cultivated tomato fruits in various genetic backgrounds and environments. Using nearly isogenic lines for the QTL, high-resolution mapping analysis delimited Brix9-2-5 to a single nucleotide polymorphism-defined recombination hotspot of 484 bp spanning an exon and intron of a fruit-specific apoplastic invertase. We suggest that the differences between the Brix9-2-5 alleles of the two species are associated with a polymorphic intronic element that modulates sink strength of tomato fruits. Our results demonstrate a link between naturally occurring DNA variation and a Mendelian determinant of a complex phenotype for a yield-associated trait.

The MHC genes have a profound effect on animal abilities to respond to specific antigens because they play a role in presenting foreign antigens to T cells during the course of the humoral or cellular immune response. In the current study, polymorphism in the MHC class I alpha2 domain was compared in 2 lines divergently selected for high (HH) or low (LL) antibody response to Escherichia coli vaccine. These lines also differ markedly in their antibody response to natural E. coli exposure and to vaccination with Newcastle disease virus, infectious bronchitis virus, and infectious bursa disease virus. Recent trials have shown that the LL chicks exhibit a significantly higher percentage of CD8+ T lymphocytes in their peripheral blood lymphocytes and spleen than HH chicks. Despite symmetrical selection intensity in both lines, polymorphism of the alpha2-domain gene was higher in the LL line than in the HH line. Among 29 single-nucleotide polymorphism positions found, 3 were unique to the HH line, 15 were unique to the LL line, and 11 were polymorphic in both lines. These single nucleotide polymorphism positions were not 100% line specific and were in agreement with the genetic variation in antibody level or cellular response still found within the selection lines. Five amino acid positions showed significant differences in polymorphism between the selection lines. These were located within the antigen-binding cleft, suggesting that these positions might influence the ability of MHC class I to bind foreign antigens and leading to differences in immunocompetence between the lines.