Osaka University

About: Osaka University is a education organization based out in Osaka, Japan. It is known for research contribution in the topics: Laser & Population. The organization has 83778 authors who have published 185669 publications receiving 5158122 citations. The organization is also known as: Ōsaka daigaku.

Silica and titanium dioxide nanoparticles cause pregnancy complications in mice.

Abstract: The increasing use of nanomaterials has raised concerns about their potential risks to human health Recent studies have shown that nanoparticles can cross the placenta barrier in pregnant mice and cause neurotoxicity in their offspring, but a more detailed understanding of the effects of nanoparticles on pregnant animals remains elusive Here, we show that silica and titanium dioxide nanoparticles with diameters of 70 nm and 35 nm, respectively, can cause pregnancy complications when injected intravenously into pregnant mice The silica and titanium dioxide nanoparticles were found in the placenta, fetal liver and fetal brain Mice treated with these nanoparticles had smaller uteri and smaller fetuses than untreated controls Fullerene molecules and larger (300 and 1,000 nm) silica particles did not induce these complications These detrimental effects are linked to structural and functional abnormalities in the placenta on the maternal side, and are abolished when the surfaces of the silica nanoparticles are modified with carboxyl and amine groups

One or more bound planets per Milky Way star from microlensing observations

Abstract: Most known extrasolar planets (exoplanets) have been discovered using the radial velocity or transit methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17–30% of solar-like stars host a planet. Gravitational microlensing on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing. These planets are at least as numerous as the stars in the Milky Way. Here we report a statistical analysis of microlensing data (gathered in 2002–07) that reveals the fraction of bound planets 0.5–10 au (Sun–Earth distance) from their stars. We find that 17^(+16)_(-9)% of stars host Jupiter-mass planets (0.3–10 M_J, where M_J = 318 M_⊕ plus and M_⊕ plus is Earth’s mass). Cool Neptunes (10–30 M_⊕ plus) and super-Earths (5–10 M_⊕ plus) are even more common: their respective abundances per star are 52^(+22)_(-29)% and 62^(+35)_(-73)% . We conclude that stars are orbited by planets as a rule, rather than the exception.