Clones identification of Sequoia sempervirens (D.Don) Endl.in Chile by using PCR-RAPDs technique     

Manuel TORAL IBAEZ  Margarita CARU  Miguel A.HERRERA  Luis GONZALEZ  Luis M.MARTIN  Jorge MIRANDA  Rafael M.NAVARRO-CERRILLO 《Journal of Zhejiang University. Science. B》2009,10(2)

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D.Don) Endl.in Chile.Ten (out of 34) clones from introduction trial located in Voipir-Viilarrica,Chile,were studied.The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction.The PCR tests were carried out employing 10-mer random primers.The amplification products were detected by electrophoresis in agarose gels.Forty nine polymorphic bands were obtained with the selected primers (BG04,BF07,BF 12,BF13,and BF 14) and were ordered according to their molecular size.The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was constructed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGMA).Of the primers tested,5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism.A total of 49 polymorphic RAPD bands were detected out of 252 bands.The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones,suggesting a geographic relationship.The results indicate that the RAPD markers permitted the identification of the assayed clones,although they are derived from the same geographic origin.  相似文献   

Clones identification of Sequoia sempervirens (D. Don) Endl. in Chile by using PCR-RAPDs technique     

Manuel Toral Ibañez  Margarita Caru  Miguel A. Herrera  Luis Gonzalez  Luis M. Martin  Jorge Miranda  Rafael M. Navarro-Cerrillo 《Journal of Zhejiang University. Science. B》2009,10(2):112-119

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D. Don) Endl. in Chile. Ten (out of 34) clones from introduction trial located in Voipir-Villarrica, Chile, were studied. The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction. The PCR tests were carried out employing 10-mer random primers. The amplification products were detected by electrophoresis in agarose gels. Forty nine polymorphic bands were obtained with the selected primers (BG04, BF07, BF12, BF13, and BF14) and were ordered according to their molecular size. The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was constructed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGMA). Of the primers tested, 5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism. A total of 49 polymorphic RAPD bands were detected out of 252 bands. The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones, suggesting a geographic relationship. The results indicate that the RAPD markers permitted the identification of the assayed clones, although they are derived from the same geographic origin. Project (No. CONICYT-FONDEF PROYECT D01 I 1008) supported by the National Commission of Science and Research of Chile  相似文献   

The importance of the International Tennis Federation's junior boys' circuit in the development of professional tennis players     

Machar Reid  Miguel Crespo  Luca Santilli  Dave Miley  James Dimmock 《Journal of sports sciences》2013,31(6):667-672

Abstract

The relationship between junior boys' tennis success, as measured by a top 20 International Tennis Federation's Junior Circuit (ITFJC) ranking, and subsequent ranking accomplishments in professional men's tennis is discussed. The names, countries, and birthdates of all players to achieve a top 20 ITFJC boys' year-end ranking from 1992 to 1998 were recorded. The progress of these players through the professional ranks was then tracked to the end of 2004. Results indicate that 91% of top 20-ranked boys achieved a professional men's ranking, while a stepwise regression analysis revealed junior ranking (JR) to be a predictor of future, professional ranking (β = 0.232, r ² = 0.054, p < 0.05). A regression equation [predicted professional rank = 78.17 + 6.31?(JR)] accounted for a significant amount of variance in professional ranking. For male players, therefore, the achievement of a top 20 junior ranking appears to be a reasonable yardstick for future, professional success. The type of surface upon which junior players develop their games was also shown to influence professional ranking highs, with play on clay courts or a combination of clay and hard courts helping to produce higher, professionally ranked players than hard court play alone (p≤ 0.01).  相似文献   

Pre-service Teachers’ False Beliefs in Superstitions and Pseudosciences in Relation to Science and Technology     

Fuertes-Prieto  Miguel Ángel  Andrés-Sánchez  Santiago  Corrochano-Fernández  Diego  Urones-Jambrina  Carmen  Delgado-Martín  Mª Laura  Herrero-Teijón  Pablo  Ruiz  Camilo 《Science & Education》2020,29(5):1235-1254

Science & Education - In order to increase scientific competence within the general population, it is important that teachers and educators have a realistic image of science and scientists,...  相似文献   

Adults with dyslexia: how can they achieve academic success despite impairments in basic reading and writing abilities? The role of text structure sensitivity as a compensatory skill     

S&#;nia Maria Pallaoro Moojen  Hosana Alves Gon&#;alves  Ana Bass&#;a  Ana Luiza Navas  Graciela de Jou  Em&#;lio S&#;nchez Miguel 《Annals of dyslexia》2020,70(1):115-140

The aim of this study was to investigate (1) whether a sample of highly educated individuals with dyslexia living under optimal personal, educational, cultural, and socioeconomic conditions continues to display core deficits in reading and writing skills during adulthood (extending prior results in Dutch, English, Hebrew, and Spanish to the Portuguese writing system); (2) whether these individuals can compensate for the effects of persistent core deficits when reading complex academic texts; (3) which cognitive resources, such as reading strategies, are used as compensatory mechanisms; and (4) whether quality of life is affected in these individuals. These questions were examined in a sample of 28 adults with dyslexia (DG) and 28 control participants (CG) paired by sex, age, education, and occupation, with a mean of 15 years of formal education. Participants completed measures of phonological awareness; decoding of syllables, words, and pseudowords; writing; reading comprehension (inferential and literal questions, recall, and sensitivity to the rhetorical structure of the target text); and quality of life. Results showed that (1) core deficits associated with dyslexia persisted into adulthood: participants with dyslexia performed worse than control subjects at all levels of phonological awareness, reading (except word reading accuracy), and spelling; (2) the groups did not differ on any measures of reading comprehension, suggesting a compensation of core deficits; (3) three compensatory mechanisms were identified: slower reading, use of text structure, and verbal ability; (4) participants with dyslexia required more family support and professional help throughout their educational careers, and had more depressive symptoms than control subjects.  相似文献   

Psychologists’ dilemmas in career counselling practice     

Paulo Miguel Cardoso  Maria Céu Taveira  Constan?a Sacadura Biscaia  Maria Gra?a Santos 《International Journal for Educational and Vocational Guidance》2012,12(3):225-241

In this study, we explored main dilemmas psychologists face in career counselling in two main professional settings: employment and education. Participants included 24 experienced Portuguese psychologists, working in employment (n?=?14) and educational (n?=?10) settings. We used consensual qualitative research to conduct and analyse semi-structured interviews. Results revealed dilemmas?? in five domains: neutrality, assessment, dual loyalty, role boundaries, and confidentiality, with the typical dilemma in the domain of neutrality. Differences between groups were found in the domains of dual loyalty and role boundaries.  相似文献   

Predictors of Familial Acculturative Stress in Asian American College Students     

Linda G. Castillo  Marion P. Zahn  Miguel A. Cano 《Journal of College Counseling》2012,15(1):52-64

The authors examined the predictors of familial acculturative stress in 85 Asian American college students. Participants were primarily 1st‐ and 2nd‐generation U.S. citizens. Results showed that perceived acculturative family conflict and family intragroup marginalization were related to higher levels of familial acculturative stress for participants. Family intragroup marginalization accounted for a statistically significant proportion of the variance in familial acculturative stress after all variables were controlled. The findings emphasize the need to recognize culture‐specific stressors of college students. Implications for college counselors are discussed.  相似文献   

“The Hardest Task”—Peer Review and the Evaluation of Technological Activities     

Vasen  Federico  Sierra Pereiro  Miguel 《Minerva》2022,60(3):375-395

Minerva - Technology development and innovation are fundamentally different from scientific research. However, in many circumstances, they are evaluated jointly and by the same processes. In these...  相似文献   

Mexican and Mexican-American children’s funds of knowledge as interventions into deficit thinking: opportunities for praxis in science education     

Miguel M. Licona 《Cultural Studies of Science Education》2013,8(4):859-872

In this case study, I use an ethnographic-style approach to understand the funds of knowledge of immigrant families living in colonias on both sides of the US/Mexico border. I focus on how these “knowledges” and concomitant experiences impact the ways we perceive and treat immigrant students who have all too often been viewed through deficit lenses that relegate them to the lowest expectations and outcomes in the classroom. I find that Mexican and Mexican-American families hold unusually sophisticated and relevant “knowledges” to mitigate their everyday lives. In this paper, I will refer to citizens of Mexico, whether they reside in Mexico or have crossed to the United States legally or without documentation for purposes of work, as Mexican. People who have crossed the border and are living in the US as legal residents or have gained citizenship are referred to as Mexican-Americans. They live a hybrid identity that is varied and dynamic, an issue that adds to the complexity of the content and contexts of this study. These families know and use these “knowledges” on a daily basis, yet they are not recognized by teachers in the US as a starting point to affirm and support immigrant children. Instead, immigrant children are relegated to the non-gifted and lower track classes where science is taught from an abstract and non-contextual and therefore less engaged basis. The approach I outline here, based on insights from my case study, can greatly improve teachers’ abilities to prepare their curricula for diversity in science education and science literacy as well as for broad expectations for student success.  相似文献   

Science Learning: A path analysis of its links with reading comprehension,question-asking in class and science achievement     

Francisco Cano  Ángela García  A.B.G. Berbén  Fernando Justicia 《International Journal of Science Education》2013,35(10):1710-1732

The purpose of this research was to build and test a conceptual model of the complex interrelationships between students' learning in science (learning approaches and self-regulation), their reading comprehension, question-asking in class and science achievement. These variables were measured by means of a test and a series of questionnaires administered to 604 ninth-grade students, and the data collected were analysed using a correlational, cross-sectional design. Results of a path analysis indicated that (a) students’ self-regulated and intentional knowledge-constructing activity (self-regulated strategy use, deep approach and knowledge-building) were what chiefly accounted for their question-asking in class; (b) question-asking (high and low levels) was related directly to reading comprehension and indirectly, through its contribution to the this, to academic achievement; (c) reading comprehension was directly and negatively associated with surface approach and indirectly and positively related to deep approach and knowledge-building; and (d) some of these variables, particularly reading comprehension, accounted for academic achievement in science. This model explained nearly 30% of the variance in academic achievement and provided a substantial and distinctive insight into the web of interrelationships among these variables. Implications for future research and science teaching and learning are discussed (e.g. the importance of supporting students' efforts to learn science in a meaningful, active and self-regulated way and of improving their reading comprehension).  相似文献