Considerations and consequences of allowing DNA sequence data as types of fungal taxa

Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.Peer reviewe

Binge Drinking, Cannabis and Tobacco Use Among Ethnic Norwegian and Ethnic Minority Adolescents in Oslo, Norway

The aim of the study was to assess prevalence and factors associated with binge drinking, cannabis use and tobacco use among ethnic Norwegians and ethnic minority adolescents in Oslo. We used data from a school-based cross-sectional survey of adolescents in junior- and senior high schools in Oslo, Norway. The participants were 10,934 adolescents aged 14 to 17 years, and just over half were females. The sample was comprised of 73.2% ethnic Norwegian adolescents, 9.8% 1st generation immigrants, and 17% 2nd generation adolescents from Europe, the US, the Middle East, Asia and Africa. Logistic regression models were applied for the data analyses. Age, gender, religion, parental education, parent-adolescent relationships, depressive symptoms and loneliness were as covariates in the regression models. Ethnic Norwegian adolescents reported the highest prevalence of binge drinking (16.1%), whereas the lowest prevalence was found among 2nd generation adolescents from Asia (2.9%). Likewise, the past-year prevalence for cannabis use ranged from 10.6% among 2nd generation Europeans and those from the US to 3.7% among 2nd generation Asians. For daily tobacco use, the prevalence ranged from 12.9% among 2nd generation Europeans and the US to 5.1% among 2nd generation Asians. Ethnicity, age, gender, religion, parental education, and parent-adolescent relationships and mental health status were significantly associated with binge drinking, cannabis and tobacco use. These factors partly explained the observed differences between ethnic Norwegians and ethnic minority adolescents in the current study. There are significant differences in substance use behaviors between ethnic Norwegian and immigrant youth. Factors like age, gender, religion, parental education and relationships and mental health status might influence the relationship between ethnicity and substance abuse. The findings have implications for planning selective- as well as universal prevention interventions

Influence of exposure to perinatal risk factors and parental mental health related hospital admission on adolescent deliberate self-harm risk

Adolescent deliberate self-harm (DSH) has been found to be associated with a range of bio-psycho-social factors. Simultaneous investigations of these factors enable more robust estimation of the independent effect of a specific risk factor by adjusting for a more complete set of covariates. However, few studies have had the ability to examine all of these factors together. This study used the linkage of population-level de-identified data collections from government agencies to investigate a range of biological, psychological, and social risk factors and their effects on adolescent risk of DSH (with or without suicidal intent). The investigation was undertaken by progressively adjusting for plausible covariates, including fetal growth status and birth order, early familial social factors, parental hospital admissions due to psychiatric disorders or DSH, and parental all-cause death. Conditional logistic regression was used for data analysis. Children’s psychiatric history was analysed to examine the extent to which it may account for the link between the risk factors and adolescent DSH risk. This study identified significant biological and perinatal social risk factors for adolescent DSH risk, including overdue birth, high birth order (=2), single or teen/young motherhood, high neighbourhood socioeconomic disadvantage, and parental psychiatric and/or DSH-related hospital admissions. Further, parental psychiatric and/or DSH-related admissions, and children’s psychiatric admissions in particular, largely attenuated the effects of the perinatal social risk factors but not the biological factors on adolescent DSH risk. These results highlight the importance of taking joint actions involving both health and social services in the prevention of adolescent DSH