Titan, the largest moon of Saturn and similar to Earth in many aspects, has unique orange-yellow colour that comes from its atmospheric haze, whose formation and dynamics are far from well understood. Present models assume that Titan's tholin-like haze formation occurs high in atmosphere through gas-phase chemical reactions initiated by high-energy solar radiation. Here we address an important question: Is the lower atmosphere of Titan photochemically active or inert? We demonstrate that indeed tholin-like haze formation could occur on condensed aerosols throughout the atmospheric column of Titan. Detected in Titan's atmosphere, dicyanoacetylene (C₄N₂) is used in our laboratory simulations as a model system for other larger unsaturated condensing compounds. We show that C4N2 ices undergo condensed-phase photopolymerization (tholin formation) at wavelengths as long as 355 nm pertinent to solar radiation reaching a large portion of Titan's atmosphere, almost close to the surface.
Aerosol light absorption has been widely considered as a contributing factor to the worsening of particulate pollution in large urban areas, primarily through its role in stabilizing the planetary boundary layer (PBL). Here, we report that absorption-dominated aerosol-radiation interaction can decrease near-surface fine particulate matter concentrations ([PM]) at a large-scale during wintertime haze events. A "warm bubble" effect by the significant heating rate of absorbing aerosols above the PBL top generates a secondary circulation, enhancing the upward motion (downward motion) and the convergence (divergence) in polluted (relatively clean) areas, with a net effect of lowering near-surface [PM].
Low solar irradiance reaching the canopy due to fog and heavy haze is a significant yield-limiting factor worldwide. However, how plants adapt to shade stress and the mechanisms underlying the reduction in leaf photosynthetic capacity and grain yield remain unclear. In this study (conducted during 2018-2021), we investigated the impact of light deprivation (60%) at the pre-anthesis and post-anthesis stages on leaf carboxylation efficiency, source-to-sink relationships, sucrose metabolism, and grain yield of wheat cultivars with contrasting shade tolerance.
Citrus pectin is an anionic polysaccharide in citrus, which may improve the stability of citrus juices. This study investigated the influence of citrus pectin on the stability of protein-polyphenol complexes in the citrus juice model system and its interaction mechanism by multispectral and molecular dynamics (MD) simulations. Dynamic light scattering (DLS) and differential scanning calorimetry (DSC) showed that the citrus pectin-proanthocyanidin-zein complex improved the model citrus juices' cloud and thermal stability.
- Corneal haze results from abnormal healing processes following injuries or surgeries, causing vision impairment due to eye opacity and irregularities, often linked to myofibroblast formation triggered by inflammation.
- Major causes of corneal haze include surgical procedures like PRK and LASIK, as well as non-surgical factors such as trauma and infections, with research focusing on the TGFβ pathway and inflammation management methods.
- Losartan, usually used for treating high blood pressure, shows promise in ophthalmology for reducing corneal fibrosis after various injuries and surgeries, leading to this review of its effectiveness and potential future applications in treating corneal haze.
Purpose: We present a patient with a primary vasoproliferative tumor (VPT) accompanied by vitreous haze and an epiretinal membrane (ERM). We report for the first time the vitreous cytokine profile from an eye with a primary VPT to explore the relationship between intraocular inflammation and these tumors.
Methods: Retrospective chart review of a single patient case.
