89 research outputs found

    Life cycle of the suctorian ciliate Ephelota plana attached to the krill Euphausia pacifica

    Get PDF
    © The Author(s), 2016. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Journal of Experimental Marine Biology and Ecology 486 (2017): 368-372, doi:10.1016/j.jembe.2016.11.003.The hypothesis that life cycle of an epibiotic suctorian ciliate Ephelota plana is adapted to the molt cycle of the krill Euphausia pacifica collected in Saanich Inlet, Canada was evaluated. The infestation prevalence of E. plana and the number of individuals attached increased from postmolt stage to premolt stage of E. pacifica, and concurrently cell growth of E. plana was observed. Budding individuals of E. plana first appeared at early premolt stage and increased to 21% at late premolt stage. Thus the life cycle of E. plana seems to be adapted to the molt cycle of E. pacifica

    Experimental Investigation of Static Channel Bonding Performance in Competitive Environment -Impact of Different MAC Procedures in 802.11ac-

    Get PDF
    Channel bonding technology, which bundles multiple adjacent channels for frame transmission, is one of the promising way for improving throughput performance in IEEE802.11ac wireless LANs. However, channel bonding technology leads to co-channel interference with other access points (APs) within the bonded channels. In our previous study, we investigated transmission performance of several commercially-available 802.11ac APs. As a result, we clarified three communication procedures from difference in method of implementation of Request To Send (RTS) / Clear To Send (CTS) or not. Furthermore, we investigated the impact of RTS/CTS on transmission performance by conducting experiments where two APs using RTS/CTS are competing in a bonded channels. However, we have not investigated transmission performance in the case that APs with different transmission procedures compete with each other in a bonded channels. Therefore, in this study, we conducted experiments using real WLAN products. Then, we compared and evaluated the communication performance in the case that two APs with different transmission procedures compete in the same channel. As a result, we showed that the AP employing CTS-to-self doesn’t set duration time in CTS frames, thereby the communication performance of the AP using RTS/CTS in channel bonding degrades due to frequent collisions in conflict channel. On the other hand, since AP not using RTS/CTS dynamically adjusts the number of data frames for each transmission opportunity to avoid frame collisions, we confirmed that the communication performance can be relatively maintained even under the competitive environment. / IEEE802.11ac規格の通信高速化技術の一つに、隣接する複数のチャネルをまとめて利用するチャネルボンディング機能がある。しかし、通信帯域が拡大するため他の無線LAN機器と競合しやすくなってしまう。先行研究では、競合しない環境の単一のAPの通信性能を調査し、オプション機能のRequest To Send (RTS) / Clear To Send (CTS)の実装方法の違いから3パターンの通信手順があることを明らかにしたうえで、RTS/CTS利用の有無が競合時に性能に与える影響を調査した。しかし、CTS-to-Selfによる競合時の影響は未だ明らかになっていない。そこで本研究では、実機を用いた実験を行い、CTS-to-Selfによる競合時の通信性能を調査するとともに、3パターンの通信手順の競合時における各通信性能の比較および評価を行った。その結果、CTS-to-selfによる通信手順ではNAV期間が確保できていないためフレーム衝突が起こりやすく、RTS/CTSを利用しチャネルボンディングさせていたAPに悪影響を与えていた。それに対して、RTS/CTSを利用しないAPは、送信機会毎のデータフレーム数を調節しながら通信していたためフレーム衝突が起こりにくく、お互いの通信性能への影響が低減されていることがわかった。電子情報通信学会 スマート無線研究会(SR), 2018年10月30日-31日, Bangkok, Thailan

    Two cases of possible neuro-Sweet disease with meningoencephalitis as the initial manifestation

    Get PDF
    We report 2 cases that were considered to be neuro-Sweet disease. They initially manifested with meningoencephalitis and no skin lesions, and rapidly improved with corticosteroid therapy. In both cases, patients complained of meningitic symptoms such as fever and headache, and HLA-B54 and -Cw1 turned out to be positive over the clinical course. Cerebrospinal fluid analysis showed increased levels of lymphocytes and protein. In case #1, fluid-attenuated inversion recovery (FLAIR), magnetic resonance imaging (MRI) and diffusion-weighted images (DWI) showed high-intensity signals in the right dorsal medulla oblongata, bilateral dorsal midbrain, and left thalamus. In case #2, FLAIR and DWI showed high-intensity signals in the bilateral cerebellar cortex and left caudate nucleus. Symptoms and MRI images were markedly improved in both cases after corticosteroid pulse therapy. According to published diagnostic criteria, these 2 cases were considered possible neuro-Sweet disease. These cases suggest that the combination of meningoencephalitis and HLA specificity is important to consider the possibility of neuro-Sweet disease, even without skin lesions

    On the origin and evolution of the asteroid Ryugu: A comprehensive geochemical perspective

    Get PDF
    Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10’s of km), <2.6 Myr after CAI formation. Subsequently, the Ryugu progenitor planetesimal was fragmented and evolved into the current asteroid Ryugu through sublimation

    The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

    Get PDF
    「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

    DOCK2 is involved in the host genetics and biology of severe COVID-19

    Get PDF
    「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

    Possible interpretations of the joint observations of UHECR arrival directions using data recorded at the Telescope Array and the Pierre Auger Observatory

    Get PDF
    corecore