31 research outputs found

    Effect of ploidy on salinity and temperature tolerance in early life stages of the Eastern oyster (\u3ci\u3eCrassostrea virginica\u3c/i\u3e)

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    The U.S. Gulf of Mexico contains the largest remaining wild oyster fishery in the world, but populations have declined in recent decades. A growing interest in off-bottom aquaculture that relies on triploid eastern oysters (Crassostrea virginica) has emerged in the Gulf region, yet these faster growing oysters suffer high mortality as adults during low salinity (\u3c5) events in warmer summer months. The combined effects of low salinity and high temperature stress on early life stages of triploid oysters are unknown. Early life stages are particularly crucial to understand because triploid oysters do not occur naturally and must be reared in hatchery settings, requiring appropriate water conditions to yield the greatest survival and growth. Thus, we tested the effects of different temperatures (28 ÂșC and 32 ÂșC) and salinities (5, 10, and 15) on diploid and triploid oysters at three critical production stages: veliger, pediveliger, and spat. Veliger survival was significantly lower for triploids relative to diploid oysters at all experimental conditions, but triploid veligers had faster growth than diploids at 32 ÂșC and salinity of 15. Pediveliger settlement was not affected by ploidy type and was reduced only at high temperature (32 ÂșC) and the lowest salinity (5). Diploid spat showed highest survival at 28 ÂșC and 15 salinity, while triploids survived best at 32 ÂșC and 15 salinity. Triploid spat attained greater shell height compared to diploids in our 6- day exposures, but growth decreased for both ploidies at lower salinities. At the salinity and temperature levels examined, diploid early life stages performed best at 28 ÂșC and 15 salinity, whereas triploids were more successful at 32 ÂșC and 15 salinity. A broader understanding of the combined effects of environmental stressors will improve the success of hatchery production yields and the resulting economic and environmental benefits of the oyster industry

    Training of child and adolescent psychiatry fellows in autism and intellectual disability

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    Patients with autism spectrum disorders and intellectual disability can be clinically complex and often have limited access to psychiatric care. Because little is known about post-graduate clinical education in autism spectrum disorder and intellectual disability, we surveyed training directors of child and adolescent psychiatry fellowship programs. On average, child and adolescent psychiatry directors reported lectures of 3 and 4 h per year in autism spectrum disorder and intellectual disability, respectively. Training directors commonly reported that trainees see 1-5 patients with autism spectrum disorder or intellectual disability per year for outpatient pharmacological management and inpatient treatment. Overall, 43% of directors endorsed the need for additional resources for training in autism spectrum disorder and intellectual disability, which, coupled with low didactic and clinical exposure, suggests that current training is inadequate

    Effect of ploidy on salinity and temperature tolerance in early life stages of the eastern oyster (Crassostrea virginica)

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    The U.S. Gulf of Mexico contains the largest remaining wild oyster fishery in the world, but populations have declined in recent decades. A growing interest in off-bottom aquaculture that relies on triploid eastern oysters (Crassostrea virginica) has emerged in the Gulf region, yet these faster growing oysters suffer high mortality as adults during low salinity (<5) events in warmer summer months. The combined effects of low salinity and high temperature stress on early life stages of triploid oysters are unknown. Early life stages are particularly crucial to understand because triploid oysters do not occur naturally and must be reared in hatchery settings, requiring appropriate water conditions to yield the greatest survival and growth. Thus, we tested the effects of different temperatures (28 ÂșC and 32 ÂșC) and salinities (5, 10, and 15) on diploid and triploid oysters at three critical production stages: veliger, pediveliger, and spat. Veliger survival was significantly lower for triploids relative to diploid oysters at all experimental conditions, but triploid veligers had faster growth than diploids at 32 ÂșC and salinity of 15. Pediveliger settlement was not affected by ploidy type and was reduced only at high temperature (32 ÂșC) and the lowest salinity (5). Diploid spat showed highest survival at 28 ÂșC and 15 salinity, while triploids survived best at 32 ÂșC and 15 salinity. Triploid spat attained greater shell height compared to diploids in our 6-day exposures, but growth decreased for both ploidies at lower salinities. At the salinity and temperature levels examined, diploid early life stages performed best at 28 ÂșC and 15 salinity, whereas triploids were more successful at 32 ÂșC and 15 salinity. A broader understanding of the combined effects of environmental stressors will improve the success of hatchery production yields and the resulting economic and environmental benefits of the oyster industry

    Life‐stage‐dependent effects of multiple flood‐associated stressors on a coastal foundational species

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    Abstract Global changes in precipitation patterns have increased the frequency and duration of flooding events. Freshwater inflows into estuaries reduce salinity levels and increase nutrient inputs, which can lead to eutrophication and impaired water quality. Oysters are important ecosystem engineers in coastal environments that are vulnerable to co‐occurring environmental stressors associated with freshwater flooding events. Successful recruitment is necessary to maintain adult oyster populations, but early life stage responses to multiple stressors are not well understood. Flood‐associated stressor conditions were observed near oyster habitats at multiple locations across the northern Gulf of Mexico during peak recruitment months in the spring and summer of 2021. In the laboratory, we examined the interactive effects of acidification, hypoxia, and low salinity on larval and juvenile life stages of the eastern oyster (Crassostrea virginica) to better understand the impact of flooding events on oyster development and survival. Salinity stress in isolation reduced larval growth and settlement, and decreased survival and growth at the juvenile stage. Hypoxia was more stressful to oyster larvae than to juveniles, whereas low pH had negative effects on juvenile growth. There were no synergistic effects of multiple flood‐associated stressors on early oyster life stages and effects were either additive or predicted by the salinity stress response. The negative impacts of flooding disturbances on recruitment processes in benthic populations need to be considered in restoration planning and flood control mitigation strategies as the frequency and intensity of extreme freshwater events continue to rise worldwide

    Training of child and adolescent psychiatry fellows in autism and intellectual disability

    No full text
    Patients with autism spectrum disorders and intellectual disability can be clinically complex and often have limited access to psychiatric care. Because little is known about post-graduate clinical education in autism spectrum disorder and intellectual disability, we surveyed training directors of child and adolescent psychiatry fellowship programs. On average, child and adolescent psychiatry directors reported lectures of 3 and 4 h per year in autism spectrum disorder and intellectual disability, respectively. Training directors commonly reported that trainees see 1-5 patients with autism spectrum disorder or intellectual disability per year for outpatient pharmacological management and inpatient treatment. Overall, 43% of directors endorsed the need for additional resources for training in autism spectrum disorder and intellectual disability, which, coupled with low didactic and clinical exposure, suggests that current training is inadequate
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