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  1. Spotted lanternfly (SLF; Lycorma delicatula White; Hemiptera: Fulgoridae) invaded the US from Asia and was first detected in 2014; currently, populations have established in 14 states primarily in the Northeast and Mid-Atlantic. It feeds voraciously on phloem sap from a broad range of host plants, with a preference for tree of heaven ( Ailanthus altissima [Sapindales: Simaroubaceae]), grapevines ( Vitis spp. [Vitales: Vitaceae]), and several common hardwood tree species. We evaluated the impacts of fourth instars and adults confined to a single branch or whole trees on gas exchange attributes (carbon assimilation [photosynthetic rate], transpiration and stomatal conductance), selected nutrients, and diameter growth using young saplings of four host tree species planted in a common garden. In general, the effects of adults on trees were greater than nymphs, although there was variation depending on tree species, pest density, and time post-infestation. Nymphs on a single branch of red maple ( Acer rubrum [Sapindales: Sapindaceae]), or silver maple ( Acer saccharinum [Sapindales: Sapindaceae]) at three densities (0, 15, or 30) had no significant effects on gas exchange. In contrast, 40 adults confined to a single branch of red or silver maple rapidly suppressed gas exchange and reduced nitrogen concentration in leaves; soluble sugars in branch wood were reduced in the fall for silver maple and in the following spring for red maple. Fourth instars confined to whole silver maple trees reduced soluble sugars in leaves and branch wood, and reduced tree diameter growth by >50% during the next growing season. In contrast, fourth instars in whole tree enclosures had no effects on black walnut ( Juglans nigra [Fagales: Juglandaceae]). SLF enclosed on tree of heaven at 80 adults per tree suppressed gas exchange after two weeks of feeding, but did not alter non-structural carbohydrates, nitrogen concentrations, or tree growth. Results suggest that moderate to heavy feeding by SLF on young maple saplings may impair tree growth, which could have implications for production nurseries and forest managers. 
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  2. Background

    Psychopathology and risky behaviors increase during adolescence, and understanding which adolescents are most at risk informs prevention and intervention efforts. Pubertal timing relative to same‐sex, same‐age peers is a known correlate of adolescent outcomes among both boys and girls. However, it remains unclear whether this relation is better explained by a plausible causal process or unobserved familial liability.

    Methods

    We extended previous research by examining associations between pubertal timing in early adolescence (age 14) and outcomes in later adolescence (age 17) in a community sample of 2,510 twins (49% boys, 51% girls).

    Results

    Earlier pubertal timing was associated with more substance use, risk behavior, internalizing and externalizing problems, and peer problems in later adolescence; these effects were small, consistent with previous literature. Follow‐up co‐twin control analyses indicated that within‐twin‐pair differences in pubertal timing were not associated with within‐twin‐pair differences in most adolescent outcomes after accounting for shared familial liability, suggesting that earlier pubertal timing and adolescent outcomes both reflect familial risk factors. Biometric models indicated that associations between earlier pubertal timing and negative adolescent outcomes were largely attributable to shared genetic liability.

    Conclusions

    Although earlier pubertal timing was associated with negative adolescent outcomes, our results suggests that these associations did not appear to be caused by earlier pubertal timing but were likely caused by shared genetic influences.

     
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