Pair-work dynamics: Stronger learners’ languaging engagement and learning outcomes for the Japanese polysemous particles ni/de

Adopting microgenetic analysis of languaging (Swain, 2006) in pair-work, this study aims to advance our understanding of learners’ developmental processes for the complex concepts of Japanese particles ni/de. Two pairs whose learning outcomes differed were chosen, and their languaging was examined, focusing on “stronger” learners, the peers who showed more targetlike knowledge of particles on fill-in-the-blank pre-test than their partners. Both interaction patterns and quality of engagement appeared to have facilitated their conceptual internalisation for the Japanese particles ni/de. A stronger learner in one of the pairs demonstrated reciprocal elaborate engagement in a collaborative pattern, and greatly improved his understanding and retained it longer-term. In contrast, a stronger learner in the other pair, who demonstrated nonreciprocal limited engagement in dominant-passive interaction, showed no development over time. Follow-up interviews revealed these peers’ differing attitudes toward pair-work, which were likely conducive to their engagement in pair-work and L2 learning outcome

Interactional Particle Use in a Japanese L2 Learner Corpus: Usage-based Analysis and Application to Teaching Japanese

ジョージア工科大学Georgia Institute of Technology多言語母語の日本語学習者横断コーパス（I-JAS）の対話データ（約15時間）を用い，言語熟達度の異なる英語母語話者（留学経験のない初級後半学習者10名，留学経験のある中級学習者10名）と日本語母語話者（10名）の相互行為詞の言語使用の実態を検討した。Bardovi-Harlig & Bastos（2011）によると，言語熟達度と語用論的マーカーの使用には複雑な関係があるが，熟達度が高い学習者ほど汎用的なマーカーの使用が多く，使用頻度も高い。本研究では，「ね」「よ」「よね」など文末に現れる相互行為詞の種類とその頻度を調査した。その結果，（1）初級後半のグループは定型表現が多く，「ね」「よ」「か」「かな」の4種類に限られていたが，中級学習者は使用の種類も9種類と広がりを見せ，頻度も多く，言語熟達度と相互行為詞の使用にはある関係性が確認できた。（2）「か」の機能にも，言語熟達度による質的な違いが見られた。初級後半学習者の注視先は，あくまで話者主体であり，会話に出てくる言葉の意味確認のために使われていたのに対し，中級学習者の注視先は会話の相手で，自分のナラティブを理解しているのかを確認するための表現（「Lock-upという居酒屋ってわかりますか」）に使われていた。つまり言語熟達度が上がると，主体と会話相手が持つ知識や経験に注視し，相互主体性が高くなるようだ。（3）「よ」に関しては，学習者の使用は非常に限られているのに対し，日本語母語話者は「よね」や「んですよ」という「よ」のバリエーション表現が多かった。相互行為詞と同様に「のだ」構文も初級の教科書に出てくるが，その多義性や文脈依存性のために，習得が難しい。I-JASの母語話者は，ナラティブにおいて背景的状況を伝えるために「んですよ」を使ったり，話し手が意見を主張しながらも聞き手に同意を求める感情的な関わりの高い「よね」を使用していた。今後は，コーパスを活用し，用法基盤モデルの研究成果を活かし，言葉をルールではなく，言葉の概念を中心に相互主体性の視点も取り入れ体系的に教えることが望ましいと思われる。By using the International Corpus of Japanese as a Second Language (I-JAS), this study aims to advance our understanding of acquisition process of interactional particles by learners of Japanese as a second language (L2). Dialogue segments from I-JAS, involving twenty adult English-speaking L2 learners of Japanese at two proficiency levels, along with a baseline group of 10 first language (L1) adults, were selected for analysis, specifically examining their use of interactional particles. Previous studies demonstrate that the complex relationship between proficiency and the use of different types of pragmatic markers exist, as proficiency is one of the sources of individual variations in L2 learners' pragmatic performance (Bardovi-Harlig & Bastos 2011). The first part of this study examined whether L2 learners' proficiency level would influence the use of interactional particles. We found that proficiency was significantly related to the overall frequency of the use of interactional particles, with the beginner group tending to use limited type of particles in formulaic expression and use them less frequently. The second half of this study investigated the discursive functions of interactional particles by each group. While both beginners and intermediate learners limited their use of yo and its variants, L1 speakers have a strong preference for the n desu yo construction and yone. Although both L2 learners groups used the question particle ka, intermediate learners show their intersubjectivity. The discussion considers the implications of promoting usage-based foreign language pragmatics teaching with corpus studies, which contributes to interactional competence and pragmatic capacity.application/pdfdepartmental bulletin pape

G-band and Hard X-ray Emissions of the 2006 December 14 flare observed by Hinode/SOT and RHESSI

We report on G-band emission observed by the Solar Optical Telescope onboard the Hinode satellite in association with the X1.5-class flare on 2006 December 14. The G-band enhancements originate from the footpoints of flaring coronal magnetic loops, coinciding with non-thermal hard X-ray bremsstrahlung sources observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager. At the available 2 minute cadence, the G-band and hard X-ray intensities are furthermore well correlated in time. Assuming that the G-band enhancements are continuum emission from a blackbody, we derived the total radiative losses of the white-light flare (white-light power). If the G-band enhancements additionally have a contribution from lines, the derived values are overestimates. We compare the white-light power with the power in hard X-ray producing electrons using the thick target assumption. Independent of the cutoff energy of the accelerated electron spectrum, the white-light power and the power of accelerated electrons are roughly proportional. Using the observed upper limit of ~30 keV for the cutoff energy, the hard X-ray producing electrons provide at least a factor of 2 more power than needed to produce the white-light emission. For electrons above 40 keV, the powers roughly match for all four of the time intervals available during the impulsive phase. Hence, the flare-accelerated electrons contain enough energy to produce the white-light flare emissions. The observed correlation in time, space, and power strongly suggests that electron acceleration and white-light production in solar flares are closely related. However, the results also call attention to the inconsistency in apparent source heights of the hard X-ray (chromosphere) and white-light (upper photosphere) sources.Comment: 15 pages, 7 figures, accepted for publication in Ap

Multiple Roles for HOXA3 in Regulating Thymus and Parathyroid Differentiation and Morphogenesis in Mouse

Hoxa3 was the first Hox gene to be mutated by gene targeting in mice and is required for the development of multiple endoderm and neural crest cell (NCC)-derived structures in the pharyngeal region. Previous studies have shown that the Hoxa3 null mutant lacks third pharyngeal pouch derivatives, the thymus and parathyroids by E18.5, and organ-specific markers are absent or downregulated during initial organogenesis. Our current analysis of the Hoxa3 null mutant shows that organ-specific domains did undergo initial patterning, but the location and timing of key regional markers within the pouch, including Tbx1, Bmp4 and Fgf8, were altered. Expression of the parathyroid marker Gcm2 was initiated but was quickly downregulated and differentiation failed; by contrast, thymus markers were delayed but achieved normal levels, concurrent with complete loss through apoptosis. To determine the cell type-specific roles of Hoxa3 in third pharyngeal pouch development, we analyzed tissue-specific mutants using endoderm and/or NCC-specific Cre drivers. Simultaneous deletion with both drivers resulted in athymia at E18.5, similar to the null. By contrast, the individual tissue-specific Hoxa3 deletions resulted in small, ectopic thymi, although each had a unique phenotype. Hoxa3 was primarily required in NCCs for morphogenesis. In endoderm, Hoxa3 temporally regulated initiation of the thymus program and was required in a cell-autonomous manner for parathyroid differentiation. Furthermore, Hoxa3 was required for survival of third pharyngeal pouch-derived organs, but expression in either tissue was sufficient for this function. These data show that Hoxa3 has multiple complex and tissue-specific functions during patterning, differentiation and morphogenesis of the thymus and parathyroids

Tomato root-associated Sphingobium harbors genes for catabolizing toxic steroidal glycoalkaloids

トマト根に定着する細菌からトマトの毒を分解する酵素を発見 --土壌微生物が植物の分泌する有害成分を解毒するメカニズムの理解に貢献--. 京都大学プレスリリース. 2023-10-02.Roots of Bloody Mary. Tomato root-associated Sphingobium harbors genes for neutralizing toxic compound. 京都大学プレスリリース. 2023-10-06.Plant roots exude various organic compounds, including plant specialized metabolites (PSMs), into the rhizosphere. The secreted PSMs enrich specific microbial taxa to shape the rhizosphere microbiome, which is crucial for the healthy growth of the host plants. PSMs often exhibit biological activities; in turn, some microorganisms possess the capability to either resist or detoxify them. Saponins are structurally diverse triterpene-type PSMs that are mainly produced by angiosperms. They are generally considered as plant defense compounds. We have revealed that α-tomatine, a steroid-type saponin secreted from tomato (Solanum lycopersicum) roots, increases the abundance of Sphingobium bacteria. To elucidate the mechanisms underlying the α-tomatine-mediated enrichment of Sphingobium, we isolated Sphingobium spp. from tomato roots and characterized their saponin-catabolizing abilities. We obtained the whole-genome sequence of Sphingobium sp. RC1, which degrades steroid-type saponins but not oleanane-type ones, and performed a gene cluster analysis together with a transcriptome analysis of α-tomatine degradation. The in vitro characterization of candidate genes identified six enzymes that hydrolyzed the different sugar moieties of steroid-type saponins at different positions. In addition, the enzymes involved in the early steps of the degradation of sapogenins (i.e., aglycones of saponins) were identified, suggesting that orthologs of the known bacterial steroid catabolic enzymes can metabolize sapogenins. Furthermore, a comparative genomic analysis revealed that the saponin-degrading enzymes were present exclusively in certain strains of Sphingobium spp., most of which were isolated from tomato roots or α-tomatine-treated soil. Taken together, these results suggest a catabolic pathway for highly bioactive steroid-type saponins in the rhizosphere

Gene expression profiling in peripheral blood leukocytes as a new approach for assessment of human stress response

Stress is the coordinated physiological processes to maintain a dynamic equilibrium under stressful conditions. The equilibrium is threatened by certain physiological and psychological stressors. Stressors trigger physiological, behavioural, and metabolic responses that are aimed at reinstating homeostasis. The hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system play an essential role in the stress response. Excessive, prolonged, or inadequate response that is termed as “allostasis” or “allostatic load” leads to pathological outcomes. Dysregulation of the HPA axis activity is involved in the pathogenesis of stress related disorders including major depression. The complex brain-immune-endocrine network regulates the HPA axis, and hereditary predisposition as well as environmental factors such as traumatic experiences in early life also modifies the capacity of an individual to cope. Therefore, it is difficult to correctly assess the complex stress response. We have developed a microarray carrying 1,467 cDNAs that were selected to specifically measure stress response in peripheral blood leukocytes. Using this tool, we have succeeded to objectively assess individual response to acute psychological stress and to detect unique expression profiles in patients with depression. Gene expression profile in peripheral blood leukocytes may be a potentially useful for the detection of disease-associated, abnormal stress responses

Murine breast cancers disorganize the liver transcriptome in a zonated manner

がんが宿主の臓器に及ぼす悪影響を捉えた --がんをもつ個体における「肝機能の空間的制御」の破綻--. 京都大学プレスリリース. 2023-02-01.The spatially organized gene expression program within the liver specifies hepatocyte functions according to their relative distances to the bloodstream (i.e., zonation), contributing to liver homeostasis. Despite the knowledge that solid cancers remotely disrupt liver homeostasis, it remains unexplored whether solid cancers affect liver zonation. Here, using spatial transcriptomics, we thoroughly investigate the abundance and zonation of hepatic genes in cancer-bearing mice. We find that breast cancers affect liver zonation in various distinct manners depending on biological pathways. Aspartate metabolism and triglyceride catabolic processes retain relatively intact zonation patterns, but the zonation of xenobiotic catabolic process genes exhibits a strong disruption. The acute phase response is induced in zonated manners. Furthermore, we demonstrate that breast cancers activate innate immune cells in particular neutrophils in distinct zonated manners, rather than in a uniform fashion within the liver. Collectively, breast cancers disorganize hepatic transcriptomes in zonated manners, thereby disrupting zonated functions of the liver

Genotoxicity of nano/microparticles in in vitro micronuclei, in vivo comet and mutation assay systems

<p>Abstract</p> <p>Background</p> <p>Recently, manufactured nano/microparticles such as fullerenes (C₆₀), carbon black (CB) and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C₆₀, CB and kaolin, an <it>in vitro </it>micronuclei (MN) test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by <it>in vivo </it>assay systems using male C57BL/6J or <it>gpt </it>delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles.</p> <p>Results</p> <p>In <it>in vitro </it>genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C₆₀, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C₆₀and kaolin, increased either or both of <it>gpt </it>and Spi^-mutant frequencies in the lungs of <it>gpt </it>delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the <it>gpt </it>genes. The G:C to C:G transversion was commonly increased by these particle instillations.</p> <p>Conclusion</p> <p>Manufactured nano/microparticles, CB, C₆₀and kaolin, were shown to be genotoxic in <it>in vitro </it>and <it>in vivo </it>assay systems.</p

Cytotoxic T Lymphocytes Regenerated from iPS Cells Have Therapeutic Efficacy in a Patient-Derived Xenograft Solid Tumor Model

Current adoptive T cell therapies conducted in an autologous setting are costly, time consuming, and depend on the quality of the patient's T cells. To address these issues, we developed a strategy in which cytotoxic T lymphocytes (CTLs) are regenerated from iPSCs that were originally derived from T cells and succeeded in regenerating CTLs specific for the WT1 antigen, which exhibited therapeutic efficacy in a xenograft model of leukemia. In this study, we extended our strategy to solid tumors. The regenerated WT1-specific CTLs had a strong therapeutic effect in orthotopic xenograft model using a renal cell carcinoma (RCC) cell line. To make our method more generally applicable, we developed an allogeneic approach by transducing HLA-haplotype homozygous iPSCs with WT1-specific TCR α/β genes that had been tested clinically. The regenerated CTLs antigen-specifically suppressed tumor growth in a patient-derived xenograft model of RCC, demonstrating the feasibility of our strategy against solid tumors