Although mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass directly onto the female via the gonopores rather than with modified pleopods 1-2 (gonopods) and/or genital papillae as in many other decapods. The single second pleopod of males of C. vittatus has a simple endopod with no apparent modifications for sperm transfer. There are no genital papillae extending from the male gonopores. The globular spermatophores are aligned in rows surrounded by a seminal secretion in the male ducts (vasa deferentia that terminate in ejaculatory ducts opening to the exterior via the gonopores). During copulation, described from time-lapse video recordings, the ventral surface of the last thoracic segment of the male, bearing the gonopores, was apposed to the ventral cephalothorax of the female. A massive amount of seminal secretion containing spermatophore ribbons, termed here the spermatophoric mass and described for the first time in a hermit crab species, was observed covering the sternites and coxae of pereopods 1-5 of a recently copulated female. It is suggested that during copulation the male emits the contents of the ejaculatory ducts directly onto the female without the aid of gonopods or genital papillae. Although spermatophore transfer is simple in C. vittatus, the presence of modified anterior pleopods or elongate genital papillae (sexual tubes) in other paguroidean species suggests the possibility of a more complex insemination process in these other hermit crabs.
Using data obtained from the Louisville Metro Emergency Medical Services, this article examined the spatial and temporal patterns of opioid overdoses in Louisville, Kentucky. We aggregated opioid overdoses to street segments and applied the optimized hot spot analysis to identify areas with significant high overdose rates. Multiple spatial regression models were used to explore the ecological risk factors potentially associated with the spatial variations of the epidemic. The results suggest an overall clustered pattern of opioid overdoses with all overdose incidents concentrated in less than 8% of all the street segments. The consecutive hot spots largely overlapped with the most disadvantaged inner-city neighborhoods in Louisville. Regression results provided statistical evidence regarding the effects of socioeconomic correlates including uninsured, vacancy rates, and criminal activity. The spatial discrepancy between the overdose hot spots and lack of medical facilities or hospitals in the disadvantaged neighborhoods points to the critical issue of health inequity.
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