A single neuron in C. elegans orchestrates multiple motor outputs through parallel modes of transmission.

Animals generate a wide range of highly coordinated motor outputs, which allows them to execute purposeful behaviors. Individual neurons in the circuits that generate behaviors have a remarkable capacity for flexibility as they exhibit multiple axonal projections, transmitter systems, and modes of neural activity. How these multi-functional properties of neurons enable the generation of adaptive behaviors remains unknown. Here, we show that the HSN neuron in C. elegans evokes multiple motor programs over different timescales to enable a suite of behavioral changes during egg laying. Using HSN activity perturbations and in vivo calcium imaging, we show that HSN acutely increases egg laying and locomotion while also biasing the animals toward low-speed dwelling behavior over minutes. The acute effects of HSN on egg laying and high-speed locomotion are mediated by separate sets of HSN transmitters and different HSN axonal compartments. The long-lasting effects on dwelling are mediated in part by HSN release of serotonin, which is taken up and re-released by NSM, another serotonergic neuron class that directly evokes dwelling. Our results show how the multi-functional properties of a single neuron allow it to induce a coordinated suite of behaviors and also reveal that neurons can borrow serotonin from one another to control behavior.

Heatwave and mortality in 31 major Chinese cities: Definition, vulnerability and implications.

Few data are available on the health impacts of heatwaves in China, and in particular, the heatwave definition and vulnerable populations remain to be identified. We collected data on daily maximum temperature and mortality from 31 Chinese capital cities during 2007-2013. A Poisson regression model allowing for over-dispersion was applied to estimate the short-term effects of heatwaves on mortality in hot season (May-September). 15 heatwave definitions combining five heat thresholds (90.0th, 92.5th, 95th, 97.5th and 99th percentiles of daily maximum temperature) and three durations (≥2, ≥3 and ≥4 days) were compared. The pooled effects were then computed using random effect meta-analysis based on the residual maximum likelihood estimation. Effect modification of heatwave-mortality association by individual-level characteristics was tested using a stratified analysis. Potential effect modification by city-level characteristics was examined by meta-regression analysis. Totally, 259 million permanent residents were covered and 4,481,090 non-accidental deaths occurred during the study period. Generally, the magnitude of heatwave impacts increased by intensities and durations of the heatwaves. Heatwave definition using daily maximum temperature ≥ 92.5th percentile with duration ≥3 days produced the best model fit. The pooled relative risks of heatwaves on non-accidental mortality at lag 0, lag 0-2 and lag 0-10 days were 1.06 (95%CI: 1.03-1.09), 1.09 (1.05-1.13) and 1.10 (1.05-1.15), respectively. Compared with non-accidental mortality, higher effect estimates of heatwaves were observed among deaths from ischemic heart diseases, stroke and respiratory diseases, although the differences were not statistically significant. Females, those ≥75 years old and the illiterates were more vulnerable to heatwaves. Cities with higher concentrations of PM2.5, higher latitudes, and lower numbers of hospital beds per 10,000 populations had higher mortality risks during heatwaves. These findings may have important implications for developing heat alert systems and early response actions on protecting the vulnerable populations from adverse health effects of heatwave in China.

Greenhouse gas emissions reduction in different economic sectors: Mitigation measures, health co-benefits, knowledge gaps, and policy implications.

To date, greenhouse gas (GHG) emissions, mitigation strategies and the accompanying health co-benefits in different economic sectors have not been fully investigated. The purpose of this paper is to review comprehensively the evidence on GHG mitigation measures and the related health co-benefits, identify knowledge gaps, and provide recommendations to promote further development and implementation of climate change response policies. Evidence on GHG emissions, abatement measures and related health co-benefits has been observed at regional, national and global levels, involving both low- and high-income societies. GHG mitigation actions have mainly been taken in five sectors: energy generation, transport, food and agriculture, household and industry, consistent with the main sources of GHG emissions. GHGs and air pollutants to a large extent stem from the same sources and are inseparable in terms of their atmospheric evolution and effects on ecosystem; thus, GHG reductions are usually, although not always, estimated to have cost effective co-benefits for public health. Some integrated mitigation strategies involving multiple sectors, which tend to create greater health benefits. The pros and cons of different mitigation measures, issues with existing knowledge, priorities for research, and potential policy implications were also discussed. Findings from this study can play a role not only in motivating large GHG emitters to make decisive changes in GHG emissions, but also in facilitating cooperation at international, national and regional levels, to promote GHG mitigation policies that protect public health from climate change and air pollution simultaneously.