Detection of laser-UV microirradiation-induced DNA photolesions by immunofluorescent staining

A low-power laser-UV microbeam of wave-length 257 nm was used for microirradiation of a small part of the nucleus of Chinese hamster cells. Following fixation in interphase or in the subsequent metaphase indirect immunofluorescent staining was performed with antiserum to photoproducts of DNA treated with far UV light. The results show that antibodies specific for UV-irradiated DNA can be used for a direct detection of laser-UV microirradiation-induced DNA photolesions. The potential usefulness of this method for investigation of the spatial arrangement of chromosomes in the interphase nucleus is discussed

An Online Oral Practice/Assessment Platform: Speak Everywhere

Despite its obvious importance, it appears that in many foreignlanguage programs, oral practice is not given as much time andattention as it deserves. Or perhaps it is more accurate to say thatforeign language professionals recognize the need for more oralpractice, but do not have at their disposal a convenient means toprovide it. An online oral practice/assessment platform, SpeakEverywhere, has been developed to fill this void. It allows instructorswithout special computer knowledge to quickly create video-basedspeaking exercises and quizzes for their students to work on outside theclassroom. The instructor can access the oral productions that thestudents submit to the system, and grade them or give individualfeedback on them either in text or audio or both. Using its flexible andeasy-to-use authoring sub-system, it is possible to create exercises ofvarious formats (e.g. Q&A, repeat after the model, structure drills,role-play, and oral reading)

培養動物細胞の速かに合成されるリボ核酸二成分の性質について

京都大学0048新制・課程博士理学博士理博第102号新制||理||61(附属図書館)1244京都大学大学院理学研究科化学専攻(主査)教授 田中 正三, 教授 波多野 博行, 教授 杉野 幸夫学位規則第5条第1項該当Kyoto UniversityDA

Stepwise Acquisition of Dialogue Act Through Human-Robot Interaction

A dialogue act (DA) represents the meaning of an utterance at the illocutionary force level (Austin 1962) such as a question, a request, and a greeting. Since DAs take charge of the most fundamental part of communication, we believe that the elucidation of DA learning mechanism is important for cognitive science and artificial intelligence. The purpose of this study is to verify that scaffolding takes place when a human teaches a robot, and to let a robot learn to estimate DAs and to make a response based on them step by step utilizing scaffolding provided by a human. To realize that, it is necessary for the robot to detect changes in utterance and rewards given by the partner and continue learning accordingly. Experimental results demonstrated that participants who continued interaction for a sufficiently long time often gave scaffolding for the robot. Although the number of experiments is still insufficient to obtain a definite conclusion, we observed that 1) the robot quickly learned to respond to DAs in most cases if the participants only spoke utterances that match the situation, 2) in the case of participants who builds scaffolding differently from what we assumed, learning did not proceed quickly, and 3) the robot could learn to estimate DAs almost exactly if the participants kept interaction for a sufficiently long time even if the scaffolding was unexpected.Comment: Published as a conference paper at IJCNN 201

p38 Mitogen-activated Protein Kinase Regulates Oscillation of Chick Pineal Circadian Clock

Extracellular signal-regulated kinase (ERK) and p38 are members of the mitogen-activated protein kinase (MAPK) family, and in some cases these kinases serve for closely related cellular functions within a cell. In a wide range of animal clock structures, ERK plays an important role in the circadian time-keeping mechanism. Here we found that immunoreactivity to p38 protein was uniformly distributed among cells in the chick pineal gland. On the other hand, a constant level of activated p38 was detected over the day, predominantly in the follicular and parafollicular pinealocytes that are potential circadian clock-containing cells. Chronic application of SB203580, a selective and reversible inhibitor of p38, to the cultured chick pineal cells markedly lengthened the period of the circadian rhythm of the melatonin release (up to 28.7 h). Noticeably, despite no significant temporal change of activated p38 level, a 4-h pulse treatment with SB203580 delayed the phase of the rhythm only when delivered during the subjective day. These results indicate a time-of-day-specific role of continuously activated p38 in the period length regulation of the chick pineal clock and suggest temporally separated regulation of the clock by two MAPKs, nighttime-activated ERK and daytime-working p38

Effects of Oral Repetition on Learners’ Japanese Word Accentuation

Japanese word accentuation is a problematic area for learnersunfamiliar with a pitch accent system. Since accent locations areunpredictable, learners are typically told to memorize them by rote,which is a time-consuming, tedious, and demanding task. It wouldcertainly be ideal for learners to learn correct accentuation withoutexplicit instruction as they learn new words. This article reports on apreliminary study that examined effects of a computer-based onlineword repetition exercise on the learning of Japanese wordaccentuation. 41 students in their 10th week and 17 students in their12th week in a 2nd-year 1st-semester Japanese course took a pretest,followed by computer-based online word repetition practice on theSpeak Everywhere system, a posttest immediately after the practice,and a delayed posttest after one week (class-and-computer condition).Out of the same group of students now in a 2nd-year 2nd-semestercourse, 22 students took a pretest, followed by two posttests in their 5thweek (class-only condition). A paired t-test (two tailed) performed on13 overlapping subjects found a significant difference between the twoconditions (t=5.58, p<.001, Cohen’s d =1.9309). The online word repetition practice produced a significant gain in accentuation scores without explicit instruction, while classroom instruction alone was not sufficient to produce a significant gain

A numerical approach for particle-vortex interactions based on volume-averaged equations

To study the dynamics of particles in turbulence when their sizes are comparable to the smallest eddies in the flow, the Kolmogorov length scale, efficient and accurate numerical models for the particle-fluid interaction are still missing. Therefore, we here extend the treatment of the particle feedback on the fluid based on the volume-averaged fluid equations (VA simulation) in the previous study of the present authors, by estimating the fluid force correlated with the disturbed flow. We validate the model against interface-resolved simulations using the immersed-boundary method. Simulations of single particles show that the history effect is well captured by the present estimation method based on the disturbed flow. Similarly, the simulation of the flow around a rotating particle demonstrates that the lift force is also well captured by the proposed method. We also consider the interaction between non-negligible size particles and an array of Taylor-Green vortices. For density ratios $\rho_d/\rho_c\geq$ 10, the results show that the particle motion captured by the VA approach is closer to that of the fully-resolved simulations than that obtained with a traditional two-way coupling simulation. The flow disturbance is also well represented by the VA simulation. In particular, it is found that history effects enhance the curvature of the trajectory in vortices and this enhancement increases with the particle size. Furthermore, the flow field generated by a neighboring particle at distances of around ten particle diameters significantly influences particle trajectories. The computational cost of the VA simulation proposed here is considerably lower than that of the interface-resolved simulation.Comment: 54 pages, 20 figure

Cycling in synchrony

The corn smut fungus uses two different mechanisms to control its cell cycle when it is infecting plants