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A rapid and cost‐effective analytical method based on ultrahigh‐performance liquid chromatography‐tandem mass spectrometry was designed and verified for simultaneously monitoring the novel acaricide pyflubumide and its metabolite (pyflubumide‐des(2‐methyl‐1oxopropyl)) in vegetables and fruits. After the extraction with acetonitrile, the samples were purified by dispersive solid‐phase extraction with multi‐walled carbon nanotubes. Detection of the two target analytes was achieved within 3.0 min using a positive electrospray ionization mode. The average recovery, intra‐day precision, and inter‐day precision of the two analytes at three spiked levels (2, 20, and 100 μg/kg) were 75.0–101.0, 0.4–4.4, and 0.6–5.3%, respectively. The limit of quantification of two compounds was 2 μg/kg, which was far below the maximum residue limits of pyflubumide in foods established by Japan and South Korea. Finally, the concentrations of pyflubumide and its metabolite in the samples were 16.6 and 7.8 μg/kg respectively, which verified the practicability and reliability of the method. The method was used to efficiently detect pyflubumide and its metabolite in real samples and was confirmed to be robust and effective for routinely analyzing both pyflubumide and its metabolite in vegetable and fruit samples. [ABSTRACT FROM AUTHOR]

The nuclear symmetry energy around or below saturation density has been extensively studied and roughly pinned down, while its behavior at suprasaturation densities is rather uncertain. Related experimental studies are being carried out or planned at facilities that offer radioactive beams worldwide. Towards the physical goal of probing the nuclear symmetry energy at high densities, π measurements in the medium nuclei 132Sn + 124Sn collisions at 300 or 200 MeV/nucleon incident beam energies are ongoing at the Radioactive Isotope Beam Facility at RIKEN in Japan. However, our studies show that the observable π−/π+ ratio in the 132Sn + 124Sn reactions at 300 or 200 MeV/nucleon incident beam energies mainly probes the symmetry energy around the saturation density. Only the π−/π+ ratio in the heavy reaction system and at relatively high incident beam energies may mainly probe the symmetry energy at suprasaturation densities. [ABSTRACT FROM AUTHOR]

In an investigation of the yeast biota involved in silage deterioration, a considerable number of strains belonging to Saccharomyces and related genera were isolated from aerobically deteriorating corn silage in Tochigi, Japan. Analysis of sequences of the internal transcribed spacer and the large-subunit rRNA gene D1/D2 domain and electrophoretic karyotyping indicated that two of the strains, NS 14(T) and NS 26, represent a novel species with close phylogenetic relationships to Kazachstania servazzii and Kazachstania unispora. It is proposed that the novel species be named Kazachstania aerobia sp. nov., with NS 14(T) (=AS 2.2384(T)=CBS 9918(T)) as the type strain.