April 2026 in “PsyArXiv (OSF Preprints)” This study found that among young adults, willingness to provide hair and fingernail samples for cortisol measurement was similar, with discomfort around sampling as the main barrier; informational videos did not significantly alter participant willingness.
3 citations
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February 2024 in “Forensic Sciences Research” In this study, researchers found that massively parallel sequencing of mitochondrial DNA (mtDNA) can improve information recovery from forensic samples, with successful full region amplification possible from as few as 2,000 mtDNA copies, albeit with variability in heteroplasmy among hair samples from the same donor.
6 citations
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June 2024 in “Drug Testing and Analysis” This review reports on the use of nails as an alternative biological matrix to hair for assessing long-term drug consumption, emphasizing that while there are clear differences between nail and hair samples, more standardized research is necessary for definitive conclusions.
8 citations
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April 2017 in “International Journal of Dermatology” This study found that applying 5% topical minoxidil twice daily significantly increased nail growth rate in healthy participants compared to untreated nails, with effects observable from the first week.
1 citations
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January 2013 in “International Journal of Physical and Social Sciences” This study found a negative correlation between lead and calcium levels in the scalp hair and finger nails of exposed and unexposed males, with variations suggesting these tissues can reflect metabolic changes over time.