Interplay of Climate Change and Air Pollution- Projection of the under-5 mortality attributable to ambient particulate matter (PM2.5) in South Asia.

Ambient fine particulate matter (PM2.5) pollution is a leading health risk factor for children under- 5 years, especially in developing countries. South Asia is a PM2.5 hotspot, where climate change, a potential factor affecting PM2.5 pollution, adds a major challenge. However, limited evidence is available on under-5 mortality attributable to PM2.5 under different climate change scenarios. This study aimed to project under-5 mortality attributable to long-term exposure to ambient PM2.5 under seven air pollution and climate change mitigation scenarios in South Asia. We used a concentration-risk function obtained from a previous review to project under-5 mortality attributable to ambient PM2.5. With a theoretical minimum risk exposure level of 2.4 µg/m3, this risk function was linked to gridded annual PM2.5 concentrations from atmospheric modeling to project under-5 mortality from 2010 to 2049 under different climate change mitigation scenarios. The scenarios were developed from the Aim/Endues global model based on end-of-pipe (removing the emission of air pollutants at the source, EoP) and 2 °C target measures. Our results showed that, in 2010-2014, about 306.8 thousand under-5 deaths attributable to PM2.5 occurred in South Asia under the Reference (business as usual) scenario. The number of deaths was projected to increase in 2045-2049 by 36.6% under the same scenario and 7.7% under the scenario where EoP measures would be partially implemented by developing countries (EoPmid), and was projected to decrease under other scenarios, with the most significant decrease (81.2%) under the scenario where EoP measures would be fully enhanced by all countries along with the measures to achieve 2 °C target (EoPmaxCCSBLD) across South Asia. Country-specific projections of under-5 mortality varied by country. The current emission control strategy would not be sufficient to reduce the number of deaths in South Asia. Robust climate change mitigation and air pollution control policy implementation is required.

Adsorption and Desorption of a Phospholipid from Single Microbubbles under Pulsed Ultrasound Irradiation for Ultrasound-Triggered Drug Delivery.

Microbubbles have potential for applications as drug and gene delivery systems, in which the release of a substance is triggered by an ultrasonic pulse. In this paper, we discuss the adsorption and desorption of a film of phospholipid on the surface of a single microbubble under ultrasound irradiation. Our optical observation system consisted of a high-speed camera, a laser Doppler vibrometer, and an ultrasound cell; 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) was used as the surfactant. The adsorption of the DMPC molecules onto the surface of the bubble was evaluated by measuring the contact angle between the bubble and a glass plate. A decrease of the contact angle of the bubble indicates desorption of the DMPC molecules from the bubble surface into the surrounding aqueous solution. The amount of DMPC molecules adsorbed on the bubble's surface is shown to decrease over time after bubble generation. The type and intensity of the pulsed ultrasound waves were varied so as to mimic ultrasound-triggered drug release. Increasing the number of cycles and the amplitude of the sound pressure of the pulsed ultrasound yielded a greater increase of the contact angle. We also measured the radial vibrations of the microbubbles in the ultrasound field. The vibrational characteristics of the microbubbles and the desorption characteristics of the DMPC molecules showed the same variation; namely, a greater sound pressure amplitude induced greater vibrational displacement and a larger amount of molecular desorption under resonance conditions. These results support the possibility of controlling drug release with pulsed ultrasound in a microbubble-based drug delivery system.

Estimation of biomass burning influence on air pollution around Beijing from an aerosol retrieval model.

We investigate heavy haze episodes (with dense concentrations of atmospheric aerosols) occurring around Beijing in June, when serious air pollution was detected by both satellite and ground measurements. Aerosol retrieval is achieved by radiative transfer simulation in an Earth atmosphere model. We solve the radiative transfer problem in the case of haze episodes by successive order of scattering. We conclude that air pollution around Beijing in June is mainly due to increased emissions of anthropogenic aerosols and that carbonaceous aerosols from agriculture biomass burning in Southeast Asia also contribute to pollution.

Synthesis of nucleobase-caged peptide nucleic acids having improved photochemical properties.

A nucleobase-caged peptide nucleic acid (PNA) having a (6-bromo-7-methoxycoumarin)-4-ylmethoxycarbonyl (Bmcmoc) caging group was newly synthesized. The Bmcmoc-caged PNAs were photolyzed to produce parent PNAs with a high photochemical efficiency. Introduction of a single Bmcmoc group was sufficient to suppress polymerase chain reaction (PCR) clamping activity and triplex invasion complex formation. Photo-mediated restoration of the PCR clamping activity was also demonstrated.

Evolutionary renovation of L/M opsin polymorphism confers a fruit discrimination advantage to ateline New World monkeys.

New World monkeys exhibit prominent colour vision variation due to allelic polymorphism of the long-to-middle wavelength (L/M) opsin gene. The known spectral variation of L/M opsins in primates is broadly determined by amino acid composition at three sites: 180, 277 and 285 (the 'three-sites' rule). However, two L/M opsin alleles found in the black-handed spider monkeys (Ateles geoffroyi) are known exceptions, presumably due to novel mutations. The spectral separation of the two L/M photopigments is 1.5 times greater than expected based on the 'three-sites' rule. Yet the consequence of this for the visual ecology of the species is unknown, as is the evolutionary mechanism by which spectral shift was achieved. In this study, we first examine L/M opsins of two other Atelinae species, the long-haired spider monkeys (A. belzebuth) and the common woolly monkeys (Lagothrix lagotricha). By a series of site-directed mutagenesis, we show that a mutation Y213D (tyrosine to aspartic acid at site 213) in the ancestral opsin of the two alleles enabled N294K, which occurred in one allele of the ateline ancestor and increased the spectral separation between the two alleles. Second, by modelling the chromaticity of dietary fruits and background leaves in a natural habitat of spider monkeys, we demonstrate that chromatic discrimination of fruit from leaves is significantly enhanced by these mutations. This evolutionary renovation of L/M opsin polymorphism in atelines illustrates a previously unappreciated dynamism of opsin genes in shaping primate colour vision.