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The effects of passive integrated transponder (PIT) tagging on cortisol release, standard metabolic rate (SMR) and daily specific growth rate (GS) were evaluated in the Gulf killifish, Fundulus grandis, a small estuarine fish native to the Gulf of Mexico. Cortisol release by individual fish was measured non‐invasively prior to PIT tagging, immediately after tagging and once per week for 1 month following tagging. Within the first 2 h of tagging, cortisol release rates were significantly elevated compared with values measured prior to tagging and significantly higher than that of fish handled identically except not implanted with PIT tags. By 1 week after PIT tagging, cortisol release rates returned to control levels. SMR, determined by intermittent‐flow respirometry and GS, defined as per cent change in body mass per day, were measured prior to PIT tagging and weekly for 1 month after tagging. Neither SMR nor GS was significantly different in tagged v. untagged fish for the duration of the study. One month after tagging, haematocrit, plasma cortisol, blood glucose and blood lactate did not differ between tagged and untagged individuals. Therefore, after a transient stress response that subsides within 1 week, PIT tagging had no significant effects on these physiological variables in F. grandis, validating its use as a method of marking this and other small fishes. [ABSTRACT FROM AUTHOR]

Criminal (drug and prostitution) charges, employment levels (weekly hours), recent substance use in the past 6 months, and primary sources of income were examined among a sample ( n = 106) of women ex-offenders who had opioid use disorders with and without methadone histories. A general linear model was tested to examine differences in relation to methadone use history. Results from a one-way MANCOVA found that those with methadone histories reported significantly higher levels of drug and prostitution charges than those without any methadone history, but no significant differences in terms of weekly hours of employment or recent substance use were observed between groups. Women ex-offenders with methadone histories reported various sources of income beyond employment, and proportionally, more of these women reported prostitution as a primary source of income. Findings suggest that methadone maintenance treatments are not sufficient in meeting the needs of women ex-offenders. [ABSTRACT FROM AUTHOR]

The hypoxia inducible factor 1 (HIF1) is a central regulator of the molecular responses of animals to low oxygen. While the hypoxia-responsiveness of HIF1 is generally attributed to the stabilization of the alpha protein subunit (HIF1α) at low oxygen, several studies on fish report increased tissue levels of HIF1A mRNA during hypoxia, suggesting transcriptional regulation. In the current study, HIF1α protein and HIF1A mRNA were determined in parallel in tissues of Gulf killifish, Fundulus grandis, exposed to short-term hypoxia (24 h at 1 mg O2 l-1). HIF1α protein was higher in brain, ovary, and skeletal muscle from fish exposed to hypoxia compared with normoxic controls by 6 h, and it remained elevated in brain and ovary at 24 h. In contrast, HIF1A mRNA levels were unaffected by hypoxia in any tissue. Moreover, HIF1α protein and HIF1A mRNA levels in the same tissues were not correlated with one another during either normoxia or hypoxia. Hence, an increase in HIF1α protein does not depend upon an increase in HIF1A mRNA during acute exposure to low oxygen in this species. The results support the widely accepted mechanism of post-translational protein stabilization, rather than new transcription, during the initial response of fish to hypoxia., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)