Environmental DNA preserved in marine sediment for detecting jellyfish blooms after a tsunami

堆積物の環境DNAで探る過去の出来事 --津波直後のクラゲ大発生を検知--. 京都大学プレスリリース. 2021-08-23.Environmental DNA (eDNA) can be a powerful tool for detecting the distribution and abundance of target species. This study aimed to test the longevity of eDNA in marine sediment through a tank experiment and to use this information to reconstruct past faunal occurrence. In the tank experiment, juvenile jack mackerel (Trachurus japonicus) were kept in flow-through tanks with marine sediment for two weeks. Water and sediment samples from the tanks were collected after the removal of fish. In the field trial, sediment cores were collected in Moune Bay, northeast Japan, where unusual blooms of jellyfish (Aurelia sp.) occurred after a tsunami. The samples were analyzed by layers to detect the eDNA of jellyfish. The tank experiment revealed that after fish were removed, eDNA was not present in the water the next day, or subsequently, whereas eDNA was detectable in the sediment for 12 months. In the sediment core samples, jellyfish eDNA was detected at high concentrations above the layer with the highest content of polycyclic aromatic hydrocarbons, reflecting tsunami-induced oil spills. Thus, marine sediment eDNA preserves a record of target species for at least one year and can be used to reconstruct past faunal occurrence

Simulation approach to model disintegration and dissolution of drug products by applying cellular automata algorithm.

富山大学・富医薬博乙第80号・横山 怜示・2021/03/03富山大

Complexation of F⁻ by Li⁺ and Mg²⁺ Ions as Inorganic Anion Acceptors in Lactone-Based Li⁺/F⁻ and Mg²⁺/F⁻ Hybrid Electrolytes for Fluoride Shuttle Batteries

The development of high-quality fluoride-ion transporting electrolytes is a crucial demand for fluoride shuttle batteries (FSBs). However, the uncontrolled chemical and electrochemical activities of fluoride ions narrow the available potential window, hindering the development of high-voltage FSB cells. We present a method for upgrading recently developed lactone-based liquid fluoride electrolytes by complexation of F⁻ with Li⁺ and Mg²⁺ ions. In the resultant Li⁺/F⁻ and Mg²⁺/F⁻ hybrid electrolytes, Li2F+ and MgF+ were the most probable soluble complexes, and the effective fluoride concentrations could reach ∼0.15 M along with excess Li⁺(Mg²⁺) ions. Unique interactions between F⁻ and Li⁺(Mg²⁺) were observed using ¹⁹F nuclear magnetic resonance spectroscopy. Li⁺(Mg²⁺) ions thus served as inorganic anion acceptors with ultimate redox stabilities to expand the negative potential window of the electrolytes to near −3 V vs SHE. The proposed complex formation was also supported by a conductometric titration method. We demonstrated the superior and versatile electrochemical performances of the Li⁺/F⁻ hybrid electrolyte, which enabled reversible charge/discharge reactions of various metal electrodes and composite electrodes in a wide range of redox series. Further, the Li⁺/F⁻ hybrid electrolyte opened valid new reaction paths for aluminum, making it a promising negative electrode in high-voltage FSB cells

Recovery of Coastal Fauna after the 2011 Tsunami in Japan as Determined by Bimonthly Underwater Visual Censuses Conducted over Five Years.

Massive tsunamis induce catastrophic disturbance in marine ecosystems, yet they can provide unique opportunities to observe the process of regeneration. Here, we report the recovery of fauna after the 2011 tsunami in northeast Japan based on underwater visual censuses performed every two months over five years. Both total fish abundance and species richness increased from the first to the second year after the tsunami followed by stabilization in the following years. Short-lived fish, such as the banded goby Pterogobius elapoides, were relatively abundant in the first two years, whereas long-lived species, such as the black rockfish Sebastes cheni, increased in the latter half of the survey period. Tropical fish species were recorded only in the second and third years after the tsunami. The body size of long-lived fish increased during the survey period resulting in a gradual increase of total fish biomass. The recovery of fish assemblages was slow at one site located in the inner bay, where the impact of the tsunami was the strongest. Apart from fish, blooms of the moon jellyfish Aurelia sp. occurred only in the first two years after the tsunami, whereas the abundances of sea cucumber Apostichopus japonicus and abalone Haliotis discus hannai increased after the second year. Although we lack quantitative data prior to the tsunami, we conclude that it takes approximately three years for coastal reef fish assemblages to recover from a heavy disturbance such as a tsunami and that the recovery is dependent on species-specific life span and habitat

Impact of Insoluble Separation Layer Mechanical Properties on Disintegration and Dissolution Kinetics of Multilayer Tablets

Dissolution and disintegration of solid dosage forms such as multiple-layer tablet with dierent active ingredients depend on formulation and properties used in the formulations, and it may sometimes result in counterintuitive release kinetics. In this manuscript, we investigate the behavior of combined acetylsalicylic acid and mefenamic acid bi- and triple-layer formulations. We show that the simulation model with a cellular automata predicted the impact of the inert layer between the dierent active ingredients on each drug release and provide a good agreement with the experimental results. Also, it is shown that the analysis based on the Noyes-Whitney equation in combination with a cellular automata-supported dissolution and disintegration numerical solutions explain the nature of the unexpected eects. We conclude that the proposed simulation approach is valuable to predict the influence of material attributes and process parameters on drug release from multicomponent and multiple-layer pharmaceutical tablets and to help us develop the drug product formulation

Location of post-tsunami visual censuses.

<p>(A) Map of the Japanese archipelago showing major ocean currents (blue arrows), locations of the survey sites (asterisks), and earthquake epicenter (double circle). <i>Pb</i>, <i>Pm</i>, and <i>Pr</i>, respectively, represent the previously recorded northern distribution limits of <i>Parupeneus barberinus</i>, <i>Parupeneus multifasciatus</i>, and <i>Plagiotremus rhinorhynchos</i> in the Pacific Ocean and the Sea of Japan according to Nakabo [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168261#pone.0168261.ref023" target="_blank">23</a>]. <i>P</i>. <i>barberinus</i> has never been reported in the Sea of Japan. (B) Magnified map of the survey area. (C) Four survey stations in and around the Moune Bay, Kesennuma, Miyagi Prefecture.</p

Average number of individuals across four locations in the Nishi-Moune Bay of major fish and invertebrate species over the first five years after the 2011 tsunami.

<p>(A) Banded goby, <i>Pterogobius elapoides</i>, (B) beauty goby, <i>Pterogobius zacalles</i>, (C) striped sandgoby, <i>Acentrogobius virgatulus</i>, (D) sevenspine goby, <i>Gymnogobius heptacanthus</i>, (E) surfperch, <i>Neoditrema ransonnetii</i>, (F) black rockfish, <i>Sebastes cheni</i>, (G) sunrise sculpin, <i>Pseudoblennius cottoides</i>, (H) greenling, <i>Hexagrammos otakii</i>, (I) moon jellyfish, <i>Aurelia</i> sp., (J) sea cucumber, <i>Apostichopus japonicus</i>, and (K) abalone, <i>Haliotis discus hannai</i>. Different symbols and colors correspond to stations shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168261#pone.0168261.g001" target="_blank">Fig 1</a>. Different letters indicate significant differences among years.</p

Body length of (A) sea cucumber, <i>Apostichopus japonicus</i>, and (B) abalone, <i>Haliotis discus hannai</i>, recorded in each survey across four sites in the Nishi-Moune Bay in the first five years after the 2011 tsunami.

<p>Raw data (open circles: all stations combined) and mean ± SD for each survey date (solid squares: only calculated when three or more data points were available) are shown. Different letters indicate significant differences among years at <i>p</i> < 0.05.</p