Elder fish means more microplastics? Alaska pollock microplastic story in the Bering Sea.

Marine microplastics are an increasingly big concern. We analyze the occurrence of microplastics in Alaska pollock (Gadus chalcogrammus) across 2+ to 12+ ages sampled from the Bering Sea. Results show that 85% of the fish have ingested microplastics and elder fish ingest more with over a third of microplastics in the 100- to 500-micrometer size range, indicating the prevalence of microplastics in Alaska pollock distributed in the Bering Sea. A positive linear relationship is obtained between fish age and microplastic size. Meanwhile, the number of polymer types increases in elder fish. The link between microplastic characteristics in Alaska pollock and the surrounding seawater suggests an extended spatial impact of microplastics. The impact of age-related microplastic ingestion on the population quality of Alaska pollock is still unknown. Therefore, we need to further investigate the potential impact of microplastics on marine organisms and the marine ecosystem, taking age as an important factor.

Inter-glacial isolation caused divergence of cold-adapted species: the case of the snow partridge.

Deciphering the role of climatic oscillations in species divergence helps us understand the mechanisms that shape global biodiversity. The cold-adapted species may have expanded their distribution with the development of glaciers during glacial period. With the retreat of glaciers, these species were discontinuously distributed in the high-altitude mountains and isolated by geographical barriers. However, the study that focuses on the speciation process of cold-adapted species is scant. To fill this gap, we combined population genetic data and ecological niche models (ENMs) to explore divergence process of snow partridge (Lerwa lerwa). Lerwa lerwa is a cold-adapted bird that is distributed from 4,000 to 5,500 m. We found 2 genetic populations within L. lerwa, and they diverged from each other at about 0.40-0.44 million years ago (inter-glacial period after Zhongliangan glaciation). The ENMs suggested that L. lerwa expanded to the low elevations of the Himalayas and Hengduan mountains during glacial period, whereas it contracted to the high elevations, southern of Himalayas, and Hengduan mountains during inter-glacial periods. Effective population size trajectory also suggested that L. lerwa expanded its population size during the glacial period. Consistent with our expectation, the results support that inter-glacial isolation contributed to the divergence of cold-adapted L. lerwa on Qinghai-Tibetan Plateau. This study deepens our understanding of how climatic oscillations have driven divergence process of cold-adapted Phasianidae species distributed on mountains.

The complete mitochondrial genome sequence of snake mackerels Paradiplospinus antarcticus (Scombroidei, Gempylidae).

For the first time, we illuminate the complete mitochondrial genome (mitogenome) sequence of the Paradiplospinus antarcticus, which is 16,988 bp in size and contains 13 protein-coding (PCGs), 2 rRNA genes, 22 tRNA genes, and one control region.The base composition of the mitogenome is 26.08% A, 26.77% T, 28.46% C and 18.69% G. Here, we selected 11 genera of species from the mostly monotypic snake mackerel family, including representative Antarctic Paradiplospinus antarcticus that have been identified, and constructed phylogenetic trees to better study the snake mackerel family.

High-Efficiency Red Organic Light-Emitting Diodes with External Quantum Efficiency Close to 30% Based on a Novel Thermally Activated Delayed Fluorescence Emitter.

Researchers have spared no effort to design new thermally activated delayed fluorescence (TADF) emitters for high-efficiency organic light-emitting diodes (OLEDs). However, efficient long-wavelength TADF emitters are rarely reported. Herein, a red TADF emitter, TPA-PZCN, is reported, which possesses a high photoluminescence quantum yield (ΦPL ) of 97% and a small singlet-triplet splitting (ΔEST ) of 0.13 eV. Based on the superior properties of TPA-PZCN, red, deep-red, and near-infrared (NIR) OLEDs are fabricated by utilizing different device structure strategies. The red devices obtain a remarkable maximum external quantum efficiency (EQE) of 27.4% and an electroluminescence (EL) peak at 628 nm with Commission Internationale de L'Eclairage (CIE) coordinates of (0.65, 0.35), which represents the best result with a peak wavelength longer than 600 nm among those of the reported red TADF devices. Furthermore, an exciplex-forming cohost strategy is adopted. The devices achieve a record EQE of 28.1% and a deep-red EL peak at 648 nm with the CIE coordinates of (0.66, 0.34). Last, nondoped devices exhibit 5.3% EQE and an NIR EL peak at 680 nm with the CIE coordinates of (0.69, 0.30).