鵜澤 武俊

type:Article 大阪教育大学・教職実践演習ミニ講座「理科の実験・観察における安全」における,コロナ禍対応のために考案・実践された理科実験安全教育上の工夫について報告する。このミニ講座は,理科の実験・観察を安全に行うために必要な知識と,それを支える理論的根拠や経験知を伝えるための授業(全5回)で構成されている。2020年度,新型コロナウィルス感染症対策のため,本稿で報告する授業はオンデマンド形式で実施された。本稿では,対面授業におけるディスカッション等に対する代替手段として,受講前後に作製された理科実験安全に関するコンセプトマップを比較することにより受講者の実験安全意識の変化を追跡する手法を提案する。 This paper reports an ingenuity in safety management capability in science experiments under COVID-19. In the present study, a change of safety consciousness in science experiments is clarified through a comparison between two concept maps constructed before and after a practice to find indications of danger in a science laboratory that appear in a video in which an experiment on neutralization of acids and bases is conducted in a first grade high school chemistry class. The practice is assigned to prospective teachers (fourth grade students in Osaka Kyoiku University) in a class of a course held in 2020 to learn how to safely conduct scientific experiments and observations. Comparing the two concept maps of each participant gives a helpful alternative to directly checking comprehension levels of the participants.

type:Article 大阪教育大学・教職実践演習ミニ講座「理科の実験・観察における安全」(2019年度)の受講者の「理科実験における危険予測力」のルーブリック評価について報告する。このミニ講座は,理科の実験・観察を安全に行うために必要な知識と,それを支える理論的根拠や経験知を学ぶための授業(全5回)で構成されている。本稿で報告する授業実践では,酸・塩基の中和実験(高校化学基礎)を撮影・編集した動画の中に現れる危険な行為や兆候を受講者に発見させる。そして,そのような危険な行為・兆候を受講者がどの程度発見できたかを,ルーブリック評価表を用いて数値化することにより,各受講者の理科実験における危険予測力を定量評価する。 This paper reports an evaluation of safety management capability in science experiments. In the present study, safety management capability in science experiments is evaluated through a rubric score of a practice to find indications of danger in a science laboratory that appear in a video in which an experiment on neutralization of acids and bases is conducted in a first grade high school chemistry class. The practice is assigned to prospective teachers (fourth grade students in Osaka Kyoiku University) in a class of a course held in 2019 to learn how to safely conduct scientific experiments and observations. A rubric score of the practice can be a measure of safety management capability in science experiments.

現在の中学校学習指導要領においては，理科において新たに放射線の性質と利用に触れることになった．ところが以前の中学校学習指導要領では放射線についての扱いがなく，放射線教育に対応できる教員や教育プログラムが十分ではなかった．このため放射線教育に用いる教育プログラムの開発が新たに行われ，その一環として放射線の生物への影響を観察する教育プログラムが開発された．その一つとして放射線の代替として紫外線を使用し，大腸菌に紫外線を照射した後の生存率を観察する模擬実験系が開発された．この模擬実験系では無菌操作を回避するために抗生物質耐性を付与した組換え大腸菌を用いた．ところで組換え大腸菌はカルタヘナ法の規制を受けるため，この模擬実験を行える学校が限られるという制約が存在する．この制約を取り除くため，模擬実験系において非組換え体大腸菌を使用可能とするための条件検討を行った．微生物実験では通常，雑菌の混入を防ぐことが必要であるが，条件により雑菌を防ぐ必要のない微生物実験も知られている．本研究では，無菌操作を行わずにこの模擬実験を行う可能性を検討した． そのため，最初に学校内の落下細菌の測定を行ない，5分間開放したシャーレでは，2日培養後に出現するコロニー数は10 cfu/シャーレより少なく，また培養時間の延長と共にコロニー数が増加することが示された．一方大腸菌は，1日培養後にコロニー数がほぼ最大に達したことから，大腸菌は大部分の雑菌より生育が速く，大腸菌のコロニー数測定には，培養時間は1日で十分であることが示された．次に，大腸菌を液体培養した後に，雑菌の混入を許す条件下で大腸菌をシャーレに塗布し，紫外線照射後の生存率を測定する実験を行った．その結果，シャーレに塗布する大腸菌の数を多くすれば，雑菌の混入を許しても，無菌操作を行った場合と同様な生存率のグラフが得られることが示された．

type:Article 大阪教育大学・教職実践演習ミニ講座「理科の実験・観察における安全」(2018年度)より,ICT教材を活用した授業実践について報告する。この講座では,理科の実験・観察を安全に行うために必要な知識を習得し,それを支える理論的根拠や経験知についてもディスカッションを通して深く理解することを目的としている。本稿にて報告する授業実践では,酸・塩基の中和実験(高校化学基礎)を撮影・編集した動画をICT教材として用い,実験時に事故を誘発し得る危険な兆候を察知する練習を行った。そして,そのような危険な兆候として,実験中の生徒の立ち位置・姿勢が悪いこと,実験卓上の整理整頓の不徹底等を見出した。 A course to learn how to safely conduct scientific experiments and observations is offered for prospective teachers (fourth grade students in Osaka Kyoiku University). This paper reports a practice in a class consisting of the course held in 2018. A video material is edited as an ICT teaching material, in which an experiment on neutralization of acids and bases is conducted in a first grade high school chemistry class. The practice in this report is aided by the ICT teaching material. The prospective teachers in the class are trained to find indications of danger in the laboratory through the video material.

Carnivorous plants exploit animals as a nutritional source and have inspired long-standing questions about the origin and evolution of carnivory-related traits. To investigate the molecular bases of carnivory, we sequenced the genome of the heterophyllous pitcher plant Cephalotus follicularis, in which we succeeded in regulating the developmental switch between carnivorous and non-carnivorous leaves. Transcriptome comparison of the two leaf types and gene repertoire analysis identified genetic changes associated with prey attraction, capture, digestion and nutrient absorption. Analysis of digestive fluid proteins from C. follicularis and three other carnivorous plants with independent carnivorous origins revealed repeated co-options of stress-responsive protein lineages coupled with convergent amino acid substitutions to acquire digestive physiology. These results imply constraints on the available routes to evolve plant carnivory.

環境教育の実習に使用可能な，従来より安全な，電気泳動後のDNA検出法を検討した．DNAを可視光で検出するViewaBlue^ⓇStain，ステインズオール，インドインブルーとメチルオレンジの３通りの染色剤を，DNA を紫外線で検出する臭化エチジウムと比較した．これらの染色剤は臭化エチジウムに比べ感度が低下したが，その中でステインズオールが高感度であった．また感度の高いアガロースを選んだ．更に費用を概算し，安全で安価なDNA検出法を選定した．

The effects of novel polyamines on aminoacyl-tRNA formation catalyzed by Escherichia coli, Sulfolobus acidocaldarius, and Thermus thermophilus HB8 S-100 extracts were investigated. These effects were diverse and differed depending on the amino acid and the enzyme used. A quaternary polyamine, tetrakis(3-aminopropyl)ammonium, inhibited phenylalanyl-tRNA synthesis catalyzed by the T. thermophilus extract, but not inhibit the other aminoacyl-tRNA formations tested. The inhibition was observed in hybrid reactions where the thermophile tRNA or extract was replaced by its E. coli counterpart, although the quaternary amine did not inhibit Phe-tRNA formation by the E. coli homologous system. Spermine relieved the inhibition of the reaction of thermophile enzyme and tRNA, but not the inhibition of the hybrid reactions. These results suggest that the branched polyamine interacts with both the thermophile enzyme and tRNA(Phe).

A continuous cell-free protein synthesis system of an extremely thermophilic eubacterium, Thermus thermophilus HB27, was constructed. This system produced MS2 phage RNA translation products at a rate of more than 5 mu g per hour per 1.9 mg of ribosomes at 65 degrees C and the production continued linearly for at least 340 min. When no polyamine was added, the system did not produce the proteins. The highest activity was recorded when O.1 mM tetrakis(3-aminopropyl)ammonium and 1.0 mM spermine were added simultaneously.

Effects of novel, naturally occurring polyamines on protein synthesis catalyzed by Thermus thermophilus cell-free extract were investigated. The results revealed the physiological importance of a branched quaternary polyamine, tetrakis(3-aminopropyl) ammonium, in thermophile protein biosynthesis. Longer polyamines than triamine supported the polypeptide synthesis at high temperature, though both the activity and the optimum temperature varied depending on polyamines added. The highest activity was found when tetrakis(3-aminopropyl)ammonium and a tetraamine were simultaneously present. The optimum temperature of the reaction supported by the combination of the branched polyamine and spermine was the highest and in accord with the optimum temperature of the bacterial growth. These results suggested an essential role of the quaternary amine in protein synthesis in vivo. This amine effectively stabilized the ternary complex between ribosomes, the messenger, and phenylalanyl-tRNA, and this stabilization may account, at least in part, for its action on the present reaction. In contrast, another branched polyamine, tris(3-aminopropyl)amine supported the activity only moderately even in the presence of another polyamine, though the tris amine stabilized the ternary complex as effectively as the quaternary amine. This result suggests the presence of another essential site for polyamine action in the thermophile polypeptide synthesis, in addition to the stabilization of the ternary complex. The effects of polyamines on MS2 RNA directed reaction resembled those on poly(U) directed polypeptide synthesis, indicating that polyamines are essential in protein biosynthesis directed by natural messengers in vivo. The quaternary amine inhibited the aminoacylation of tRNA(Phe), and the inhibition was canceled by the addition of another polyamine. When phenylalanyl-tRNA instead of free phenylalanine was added to the reaction mixture in order to investigate the effect of polyamines on polypeptide formation, single addition of tetrakis(3-aminopropyl)ammonium was enough for the highest activity, and the synergistic effect disappeared. The results indicate that the role of spermine in the synergism is to relieve the inhibition of aminoacylation caused by the quaternary amine.