Abstract
A large fraction of the uncertainty around future global warming is due to the cooling effect of aerosol-liquid cloud interactions, and in particular to the elusive sign of liquid water path ...(LWP) adjustments to aerosol perturbations. To quantify this adjustment, we propose a causal approach that combines physical knowledge in the form of a causal graph with geostationary satellite observations of stratocumulus clouds. This allows us to remove confounding influences from large-scale meteorology and to disentangle counteracting physical processes (cloud-top entrainment enhancement and precipitation suppression due to aerosol perturbations) on different timescales. This results in weak LWP adjustments that are time-dependent (first positive then negative) and meteorological regime-dependent. More importantly, the causal approach reveals that failing to account for covariations of cloud droplet sizes and cloud depth, which are, respectively, a mediator and a confounder of entrainment and precipitation influences, leads to an overly negative aerosol-induced LWP response. This would result in an underestimation of the cooling influence of aerosol-cloud interactions.
Air pollution is the single most important environmental health risk, causing about 7 million premature deaths annually worldwide. China is the world's largest emitter of anthropogenic air ...pollutants, which causes major negative health consequences. The Chinese government has implemented several policies to reduce air pollution, with success in some but far from all sectors. In addition to the health benefits, reducing air pollution will have side-benefits, such as an increase in the electricity generated by the solar photovoltaic panels via an increase in surface solar irradiance through a reduction of haze and aerosol-impacted clouds. We use the global aerosol-climate model ECHAM6-HAM2 with the bottom-up emissions inventory from the Community Emission Data System and quantify the geographically specific increases in generation and economic revenue to the Chinese solar photovoltaic fleet as a result of reducing or eliminating air pollution from the energy, industrial, transport, and residential and commercial sectors. We find that by 2040, the gains will be substantial: the projected solar photovoltaic fleet would produce between 85-158 TWh/year of additional power in clean compared to polluted air, generating US$6.9-10.1 billion of additional annual revenues in the solar photovoltaic sector alone. Furthermore, we quantify the cost of adopting best-practice emission standards in all sectors and find that the revenue gains from the increased solar photovoltaic generation could offset up to about 13-17% of the costs of strong air pollution control measures designed to reach near-zero emissions in all sectors. Hence, reducing air pollution in China will not only have clear health benefits, but the side-effect of increased solar power generation would also offset a sizeable share of the costs of air pollution control measures.
The global aerosol–climate model ECHAM6.3–HAM2.3 (E63H23)
as well as the previous model versions ECHAM5.5–HAM2.0 (E55H20) and ECHAM6.1–HAM2.2
(E61H22) are evaluated using global observational ...datasets for clouds and
precipitation. In E63H23, the amount of low clouds, the liquid and ice water path, and
cloud radiative effects are more realistic than in previous model versions.
E63H23 has a more physically based aerosol activation scheme, improvements
in the cloud cover scheme, changes in the detrainment of convective clouds,
changes in the sticking efficiency for the accretion of ice crystals by snow,
consistent ice crystal shapes throughout the model, and changes in mixed-phase
freezing; an inconsistency in ice crystal number concentration (ICNC) in
cirrus clouds was also removed. Common biases in ECHAM and in E63H23 (and in
previous ECHAM–HAM versions) are a cloud amount in stratocumulus
regions that is too low and deep convective clouds over the Atlantic and Pacific oceans
that form too close to the continents (while tropical land precipitation is
underestimated). There are indications that ICNCs are overestimated in
E63H23. Since clouds are important for effective radiative forcing due to
aerosol–radiation and aerosol–cloud interactions (ERFari+aci) and
equilibrium climate sensitivity (ECS), differences in ERFari+aci
and ECS between the model versions were also analyzed. ERFari+aci is weaker
in E63H23 (−1.0 W m−2) than in E61H22 (−1.2 W m−2) (or E55H20;
−1.1 W m−2). This is caused by the weaker shortwave ERFari+aci
(a new aerosol activation scheme and sea salt emission parameterization in
E63H23, more realistic simulation of cloud water) overcompensating for the
weaker longwave ERFari+aci (removal of an inconsistency in ICNC in
cirrus clouds in E61H22). The decrease in ECS in E63H23 (2.5 K) compared to E61H22 (2.8 K) is due to
changes in the entrainment rate for shallow convection (affecting the cloud
amount feedback) and a stronger cloud phase feedback. Experiments with minimum cloud droplet number concentrations (CDNCmin) of
40 cm−3 or 10 cm−3 show that a higher value of CDNCmin reduces
ERFari+aci as well as ECS in E63H23.
Congenital myasthenic syndromes (CMS) are rare, genetically and phenotypically diverse disorders of neuromuscular transmission. Data on prevalence among children are scarce. Whole exome sequencing ...facilitated discovery of novel CMS mutations and enabled targeted treatment. Our aim was to identify the prevalence, genetic subtypes and clinical characteristics of CMS in pediatric population of Slovenia.
In this observational, national, cross-sectional study, medical records were retrospectively reviewed. Children with genetically confirmed CMS, referred over a 19 – year period (2000–2018) to the University Medical Centre, Ljubljana, Slovenia, were included in the study. Genetic and phenotypic characteristics were collected and prevalence of CMS in children was calculated.
Eight children with a confirmed genetic mutation in 5 different genes (CHRNE, CHRND, RAPSN, CHAT, MUSK) causative of the CMS were identified. Calculated prevalence of genetically confirmed CMS was 22.2 cases per 1.000.000 children at the end of 2018.
The prevalence of genetically confirmed CMS in Slovenian children at the end of 2018 exceeds previously reported prevalence by more than two-fold, which suggests that prevalence in the literature is likely to be underestimated. Two extremely rarely detected mutations in MUSK and CHRND gene were detected and patient's clinical descriptions add important information on genotype-phenotype correlation.
•The prevalence of CMS in Slovenian children exceeds previously reported data by more than two-fold.•CMS is often a missed diagnosis and prevalence is likely to be underestimated.•Electrophysiological testing (RNS-EMG) often gave false negative results in the first year of life in our cohort.•Genetic molecular testing has improved diagnostics and enabled more targeted treatment.•Disease awareness among healthcare professionals and reliable diagnostic tests are important.
Ramelteon is a selective melatonin receptor (MT(1) and MT(2)) agonist that has been approved by the US Food and Drug Administration for the treatment of insomnia characterized by difficulty with ...sleep onset. It is the only approved sleep-promoting medication that does not have a direct sedating effect, but rather enhances sleep through effects on sleep regulatory mechanisms within the suprachiasmatic nucleus. Ramelteon has been shown to have no abuse liability and therefore is not scheduled by the U.S. Drug Enforcement Agency as a controlled substance. It is available as an 8 mg tablet, which should be taken approximately 30 minutes prior to bedtime. The FDA approval contains no limitation on how long the medication may be prescribed.
Abstract
Biomass burning (BB) is a major source of aerosols that remain the most uncertain components of the global radiative forcing. Current global models have great difficulty matching observed ...aerosol optical depth (AOD) over BB regions. A common solution to address modelled AOD biases is scaling BB emissions. Using the relationship from an ensemble of aerosol models and satellite observations, we show that the bias in aerosol modelling results primarily from incorrect lifetimes and underestimated mass extinction coefficients. In turn, these biases seem to be related to incorrect precipitation and underestimated particle sizes. We further show that boosting BB emissions to correct AOD biases over the source region causes an overestimation of AOD in the outflow from Africa by 48%, leading to a double warming effect compared with when biases are simultaneously addressed for both aforementioned factors. Such deviations are particularly concerning in a warming future with increasing emissions from fires.
Winter quiescence in fishes is not uncommon, however understanding the mechanisms that cause dormancy are poorly understood. This study highlights the physiological stress temperature places on ...locomotor musculature and its consequences on whole organism locomotion. Cunner and tautog experience temperatures ranging from 0 to 25 °C and enter dormancy at ~10 °C. We aimed to address the question: how do winter temperatures affect steady swimming and muscle contraction kinetics in cunner? Fishes were collected and housed at 5, 10, 15, or 20 °C. Gait transition speed and fin beat frequency were measured at each acclimation temperature. Twitch and tetanus kinetics were recorded from the aerobic locomotor muscle, which is responsible for the power stroke during swimming. Fish acclimated to colder temperatures (5, 10 °C) demonstrated lower gait transition speeds than the warm temperature treatments. Similarly, twitch kinetics were slower in muscle acclimated at ≤10 °C. Locomotor muscle from tautog was significantly slower to contract and relax than cunner when tested at 5 and 10 °C. These results suggest that muscle acclimation differs in these closely related labrids from the same habitat. Additionally, these results suggest that cunner locomotor musculature can maintain greater performance at a wider range of temperatures. Cunner occupy more northern latitudes which likely allows for greater performance shifts in response to temperature. However, when temperatures get cold enough muscle function is reduced, perhaps contributing to their overwintering ecology.
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