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Marine invertebrate larvae have often been reared in artificial rather than natural seawater, either for convenience or to avoid potentially confounding effects of unknown contaminants. This study sought to determine the impact of artificial seawater on various aspects of development for three marine invertebrate species. We examined the impact of Instant Ocean on growth, survival, and fecundity of the deposit-feeding polychaete Capitella teleta at 2 salinities: 24 and 34 ppt; the impact on survival, growth rate, and time to metamorphic competence for the slipper limpet Crepidula fornicata; and the impact on larval growth for the sea star Asterias forbesi. Juveniles of C. teleta survived better in natural seawater than in Instant Ocean at both salinities but at the higher salinity grew more quickly in Instant Ocean; fecundity was not significantly affected by the type of seawater used at either salinity. Using Instant Ocean in place of natural seawater had no pronounced impact on the survival of C. fornicata larvae or on how long it took them to become competent to metamorphose; however, larvae grew somewhat more quickly in Instant Ocean than in natural seawater for the first 4 days of development, but by day 7 they were about 4.5% larger if they had been reared in seawater. The type of seawater used affected the growth of A. forbesi larvae, with larvae growing significantly more slowly in Instant Ocean than in natural seawater, no matter how growth was measured. In conclusion, our results suggest that although Instant Ocean may be a reasonable substitute for natural seawater for work with some species, using it may affect experimental outcomes in some aspects of work with other species.

Rising atmospheric CO2 reduces seawater pH causing ocean acidification (OA). Understanding how resilient marine organisms respond to OA may help predict how community dynamics will shift as CO2 continues rising. The common slipper shell snail Crepidula fornicata is a marine gastropod native to eastern North America that has been a successful invader along the western European coastline and elsewhere. It has also been previously shown to be resilient to global change stressors. To examine the mechanisms underlying C. fornicata’s resilience to OA, we conducted two controlled laboratory experiments. First, we examined several phenotypes and genome-wide gene expression of C. fornicata in response to pH treatments (7.5, 7.6, and 8.0) throughout the larval stage and then tested how conditions experienced as larvae influenced juvenile stages (i.e., carry-over effects). Second, we examined genome-wide gene expression patterns of C. fornicata larvae in response to acute (4, 10, 24, and 48 h) pH treatment (7.5 and 8.0). Both C. fornicata larvae and juveniles exhibited resilience to OA and their gene expression responses highlight the role of transcriptome plasticity in this resilience. Larvae did not exhibit reduced growth under OA until they were at least 8 days old. These phenotypic effects were preceded by broad transcriptomic changes, which likely served as an acclimation mechanism for combating reduced pH conditions frequently experienced in littoral zones. Larvae reared in reduced pH conditions also took longer to become competent to metamorphose. In addition, while juvenile sizes at metamorphosis reflected larval rearing pH conditions, no carry-over effects on juvenile growth rates were observed. Transcriptomic analyses suggest increased metabolism under OA, which may indicate compensation in reduced pH environments. Transcriptomic analyses through time suggest that these energetic burdens experienced under OA eventually dissipate, allowing C. fornicata to reduce metabolic demands and acclimate to reduced pH. Carry-over effects from larval OA conditions were observed in juveniles; however, these effects were larger for more severe OA conditions and larvae reared in those conditions also demonstrated less transcriptome elasticity. This study highlights the importance of assessing the effects of OA across life history stages and demonstrates how transcriptomic plasticity may allow highly resilient organisms, like C. fornicata, to acclimate to reduced pH environments.

Precipitation variability is a potentially important driver of infectious diseases that are leading causes of child morbidity and mortality worldwide. Disentangling the links between precipitation variability and disease risk is crucial in a changing climate. We aimed to investigate the links between precipitation variability and reported symptoms of infectious disease (cough, fever, and diarrhoea) in children younger than 5 years.We used nationally representative survey data collected between 2014 and 2019 from Demographic and Health Survey (DHS) surveys for 32 low-income to middle-income countries in combination with high-resolution precipitation data (via the Climate Hazards Group InfraRed Precipitation with Station dataset). We only included DHS data for which interview dates and GPS coordinates (latitude and longitude) of household clusters were available. We used a regression modelling approach to assess the relationship between different precipitation variability measures and infectious disease symptoms (cough, fever, and diarrhoea), and explored the effect modification of different climate zones and disease susceptibility factors.Our global analysis showed that anomalously wet conditions increase the risk of cough, fever, and diarrhoea symptoms in humid, subtropical regions. These health risks also increased in tropical savanna regions as a result of anomalously dry conditions. Our analysis of susceptibility factors suggests that unimproved sanitation and unsafe drinking water sources are exacerbating these effects, particularly for rural populations and in drought-prone areas in tropical savanna.Weather shifts can affect the survival and transmission of pathogens that are particularly harmful to young children. As our findings show, the health burden of climate-sensitive infectious diseases can be substantial and is likely to fall on populations that are already among the most disadvantaged, including households living in remote rural areas and those lacking access to safe water and sanitation infrastructure.University of California, San Diego FY19 Center Launch programme.

Rising atmospheric CO2 reduces seawater pH causing ocean acidification (OA). Understanding how resilient marine organisms respond to OA may help predict how community dynamics will shift as CO2 continues rising. The common slipper shell snail Crepidula fornicata is a marine gastropod native to eastern North America that has been a successful invader along the western European coastline and elsewhere. It has also been previously shown to be resilient to global change stressors. To examine the mechanisms underlying C. fornicata’s resilience to OA, we conducted two controlled laboratory experiments. First, we examined several phenotypes and genome-wide gene expression of C. fornicata in response to pH treatments (7.5, 7.6, and 8.0) throughout the larval stage and then tested how conditions experienced as larvae influenced juvenile stages (i.e., carry-over effects). Second, we examined genome-wide gene expression patterns of C. fornicata larvae in response to acute (4, 10, 24, and 48 h) pH treatment (7.5 and 8.0). Both C. fornicata larvae and juveniles exhibited resilience to OA and their gene expression responses highlight the role of transcriptome plasticity in this resilience. Larvae did not exhibit reduced growth under OA until they were at least 8 days old. These phenotypic effects were preceded by broad transcriptomic changes, which likely served as an acclimation mechanism for combating reduced pH conditions frequently experienced in littoral zones. Larvae reared in reduced pH conditions also took longer to become competent to metamorphose. In addition, while juvenile sizes at metamorphosis reflected larval rearing pH conditions, no carry-over effects on juvenile growth rates were observed. Transcriptomic analyses suggest increased metabolism under OA, which may indicate compensation in reduced pH environments. Transcriptomic analyses through time suggest that these energetic burdens experienced under OA eventually dissipate, allowing C. fornicata to reduce metabolic demands and acclimate to reduced pH. Carry-over effects from larval OA conditions were observed in juveniles; however, these effects were larger for more severe OA conditions and larvae reared in those conditions also demonstrated less transcriptome elasticity. This study highlights the importance of assessing the effects of OA across life history stages and demonstrates how transcriptomic plasticity may allow highly resilient organisms, like C. fornicata, to acclimate to reduced pH environments.

There is limited available literature examining factors that predispose patients to the development of LMC after stereotactic radiosurgery (SRS) for brain metastases. We sought to evaluate risk factors that may predispose patients to LMC after SRS treatment in this case-control study of patients with brain metastases who underwent single-fraction SRS between 2011 and 2016. Demographic and clinical information were collected retrospectively for 19 LMC cases and 30 controls out of 413 screened patients with brain metastases. Risk factors of interest were evaluated by univariate and multivariate logistic regression analyses and overall survival rates were evaluated by Kaplan-Meier survival analysis. About 5% of patients with brain metastases treated with SRS developed LMC. Patients with LMC (median 154 days, 95% CI 33-203 days) demonstrated a poorer overall survival than matched controls (median 417 days, 95% CI 121-512 days, p = 0.002). The most common primary tumor histologies that lead to the development of LMC were non-small cell lung cancer (36.8%), breast cancer (26.3%), and melanoma (21.1%). No association was found between the risk of LMC and the location of the brain lesion or total volume of brain metastases. Prior surgical resection of brain metastases before SRS was associated with a 6.5 times higher odds (95% CI 1.45-29.35, p = 0.01) of developing LMC post-radiosurgery compared to those with no prior resections of brain metastases. Additionally, adjuvant WBRT may help to reduce the risk of LMC and can be considered in decision-making for patients who have had brain metastasectomy.

Ocean pH has been declining since the start of the Industrial Revolution, and is predicted to continue declining for at least another 200 years. Although the chemical cues that induce larval metamorphosis in marine invertebrates in part determine the distribution and persistence of many coastal marine communities, few studies have examined the effects of ocean acidification on the timing of metamorphic competence or the ability of larval invertebrates to metamorphose in response to environmental cues. Working with larvae of the marine gastropod Crepidula fornicata, we examined the impacts of sudden, short-term (2 h), and prolonged (several weeks) exposure to reduced pH as low as 7.5 on larval survival and growth, the onset of metamorphic competence, and the ability of larvae to perceive inductive cues and metamorphose in their presence. Unexpectedly, although larvae reared at pH 7.5 grew more slowly and took longer to become competent to metamorphose, exposure to acidified conditions did not appreciably impair larval cue perception for metamorphosis.

Marine invertebrate larvae have often been reared in artificial rather than natural seawater, either for convenience or to avoid potentially confounding effects of unknown contaminants. This study sought to determine the impact of artificial seawater on various aspects of development for three marine invertebrate species. We examined the impact of Instant Ocean on growth, survival, and fecundity of the deposit-feeding polychaete