A communal catalogue reveals Earth's multiscale microbial diversity

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

A communal catalogue reveals Earth’s multiscale microbial diversity

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

Sports Participation and Juvenile Delinquency: A Meta-Analytic Review

Participation in sports activities is very popular among adolescents, and is frequently encouraged among youth. Many psychosocial health benefits in youth are attributed to sports participation, but to what extent this positive influence holds for juvenile delinquency is still not clear on both the theoretical and empirical level. There is much controversy on whether sports participation should be perceived as a protective or a risk factor for the development of juvenile delinquency. A multilevel meta-analysis of 51 published and unpublished studies, with 48 independent samples containing 431 effect sizes and N = 132,366 adolescents, was conducted to examine the relationship between sports participation and juvenile delinquency and possible moderating factors of this association. The results showed that there is no overall significant association between sports participation and juvenile delinquency, indicating that adolescent athletes are neither more nor less delinquent than non-athletes. Some study, sample and sports characteristics significantly moderated the relationship between sports participation and juvenile delinquency. However, this moderating influence was modest. Implications for theory and practice concerning the use of sports to prevent juvenile delinquency are discussed. Keywords Sports participation Juvenile delinquency Multilevel meta-analysis Revie

How the menstrual cycle and menstruation affect sporting performance: experiences and perceptions of elite female rugby players

Objectives To explore athletes’ past and current experiences and perceptions of the menstrual cycle in relation to its impact on sporting performance. Methods 15 international female rugby players participated in individual semi-structured interviews (age: 24.5±6.2 years). All interviews were recorded and transcribed verbatim, resulting in 37 376 words of text for descriptive and thematic analysis. Inter-rater reliability checks resulted in a concordance of agreement of 83%. Results Almost all athletes (93%) reported menstrual cycle-related symptoms. Thirty-three per cent perceived heavy menstrual bleeding and 67% considered these symptoms impaired their performances. Two-thirds of athletes self-medicated to alleviate symptoms. Thematic analysis generated 262 meaning units, 38 themes, 10 categories and 4 general dimensions. The four general dimensions were: (1) symptoms: physiological and psychological menstrual cycle-related symptoms such as dysmenorrhoea, flooding, reduced energy levels, worry, distraction, fluctuating emotions and reduced motivation; (2) impact: perceived impact of menstruation on different aspects of daily lives and performance including negative and neutral responses; (3) resolution: the methods/ approaches in dealing with menstruation-related concerns including accepting, or adapting and managing symptoms with self-medication or expert treatment; (4) support: available support and comfortability in discussing menstrual cycle-related issues. Conclusions This study provides the first in-depth insight into athlete’s experiences of the menstrual cycle and perceived impact on training and competition. It highlights individual responses to menstrual ’issues’ and emphasises the need for clinicians and support staff to undertake menstrual cycle profiling, monitoring and continue to develop awareness, openness, knowledge and understanding of the menstrual cycle