The role of long-range dispersal in the coexistence of sexual and asexual relatives in a population of hermaphrodite flowering plants is investigated. In these populations, growth and reproduction often occur during a sedentary stage that is then followed by dispersal of propagules. These two stages are clearly distinguishable and show strong seasonality. A modeling approach that accurately describes this kind of dynamics of mixed populations is a system of two nonlinear integro-difference equations. It is shown that this kind of model can accommodate coexistence of the two different reproductive types.
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http://dx.doi.org/10.1007/s11538-009-9416-8 | DOI Listing |
Mol Ecol
January 2025
School of Biological Sciences, Monash University, Clayton, Victoria, Australia.
Biochemical and evolutionary interactions between mitochondrial and nuclear genomes ('mitonuclear interactions') are proposed to underpin fundamental aspects of biology including evolution of sexual reproduction, adaptation and speciation. We investigated the role of pre-mating isolation in maintaining functional mitonuclear interactions in wild populations bearing diverged, putatively co-adapted mitonuclear genotypes. Two lineages of eastern yellow robin Eopsaltria australis-putatively climate-adapted to 'inland' and 'coastal' climates-differ by ~7% of mitogenome nucleotides, whereas nuclear genome differences are concentrated into a sex-linked region enriched with mitochondrial functions.
View Article and Find Full Text PDFArch Dis Child
December 2024
Royal College of Paediatrics and Child Health, London, UK.
Introduction: This systematic review aims to collate evidence of the causes of genital bleeding, other than child sexual abuse and accidental injuries, presenting in prepubertal girls. It provides an update to the 2015 Royal College of Paediatrics and Child Health publication 'The Physical Signs of Child Sexual Abuse', an evidence-based review also known as the Purple Book.
Methods: MEDLINE, EMBASE and Scopus databases were searched for studies published between March 2014 and June 2023.
Sexually transmitted infection rates are increasing in the United States, with significant increases in the rates of syphilis among patients of reproductive age and, subsequently, congenital syphilis. Syphilis screening is recommended in sexually active patients 15 to 44 years of age in communities with high syphilis rates and in all pregnant patients at the time of diagnosis or prenatal intake, in the third trimester, and at delivery. Screening for chlamydia and gonorrhea is currently recommended in asymptomatic, sexually active patients younger than 25 years, as well as in older patients with risk factors.
View Article and Find Full Text PDFArch Sex Behav
December 2024
Child and Adolescent Studies, Faculty of Social and Behavioral Sciences, Utrecht University, Heidelberglaan 1, P.O. Box 80140, 3508 TC, Utrecht, The Netherlands.
Amidst the predominantly risk-focused narrative of adolescent sexual health, sexual pleasure is often overlooked. This study examined the association between adolescents' experienced sexual pleasure and profiles of sexual double standard (SDS) norms, which prescribe divergent expectations of sexuality based on gender. The sample consisted of 209 Dutch adolescents aged 16-20 years (57% female) who have had sexual intercourse.
View Article and Find Full Text PDFJ Child Adolesc Trauma
December 2024
School of Nursing, Faculty of Health Sciences, University of Botswana, Gaborone, Botswana.
Background: People living with HIV experience traumatic incidents at higher rates than the general population; and research has documented significant association between trauma exposure and the development of mental disorders. Mental health problems have a a negative impact on anti-retroviral treatment adherence. All of these psychosocial concerns play a role in potentially increasing HIV transmission to sexual partners resulting in increased incidence rates.
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