Correction: Massively Parallelized Pollen Tube Guidance and Mechanical Measurements on a Lab-on-a-Chip Platform
[This corrects the article DOI: 10.1371/journal.pone.0168138.].
ZnO nanoparticles effect on pollen grain germination and pollen tube elongation
Plant germ cells, such as pollen grains, can be affected by exposure to metal nanoparticles (NPs) that have diffused into the environment. The germination and tube elongation of pollen grain (Lilium longiflorum) exposed to low-solubility NPs was observed. The germination rate of pollen grain exposed to 100 mg L−1 ZnO NP dispersion decreased significantly from controls and exposure of the other NPs. On the other hand, when pollens were exposed to ionic solutions in which particles were removed from the 100 mg L−1 ZnO NP dispersion, the germination rates were equivalent to those in the control pollens. On the contrary, decrease of the germination rate compared to controls was small in the exposure to ZnCl2 solution, which contained a larger amount of water-soluble Zn2+ than ZnO NP dispersion. From these results, it was concluded that fine ZnO NP may adhere to pollens, due to the cohesive property of nanoparticles, and Zn2+ dissolved at the interface may be continuously absorbed by pollens. When pollen was exposed to ZnO NP, a spot with a high Ca2+ local concentration was observed at the tip of the pollen tube. On the contrary, simultaneous exposure to antagonistic ZnO NP and CaCl2 resulted in no decrease in the germination rate. From the above, it is considered that upon exposure to ZnO NP, cells absorb Zn2+ depending on the specific solubility of ZnO NP. Despite the low solubility of zinc oxide nanoparticle, pollen cell-attached particles inhibited germination and elongation of pollen tube by continuous Zn2+ dissolution from particles and Zn2+ absorption by the cell.
The administration of the courts
Section 28 of Article VI of the State Constitution provides that the Chief Judge of the Court of Appeals is the Chief Judge of the State and its chief judicial officer. The Chief Judge appoints a Chief Administrator of the Courts (or Chief Administrative Judge of the Courts if the appointee is a judge) with the advice and consent of the Administrative Board of the Courts. The Administrative Board consists of the Chief Judge as chair and the Presiding Justices of the four Appellate Divisions of the Supreme Court. The Chief Judge establishes statewide administrative standards and policies after consultation with the Administrative Board and approval by the Court of Appeals.