174 research outputs found
Task design to foster the competence in social decision making on mathematics education
As society continues to progress, it is becoming increasingly more important to mathematically deal with issues, take risks and uncertainty into account, clarify the grounds for participating in judgements or decision making, and make critical deliberations. This competence is defined as "decision making”. We present the design of a task about saving more lives with automatic external defibrillators (AEDs) in order to foster this competency in mathematics lessons. In methodological terms, we use Lesson Study to carefully anticipate the process of students’ finding and solving problems. We review the design from different viewpoints, such as “What times and how should all the students in the class study?” or “When and what kind of materials should be presented?
Effects of verapamil and lidocaine on two components of the re-entry circuit of verapamil-sensitive idiopathic left ventricular tachycardia
AbstractOBJECTIVESWe characterized pharmacologically the slow conduction zone of verapamil-sensitive idiopathic left ventricular tachycardia (ILVT) with regard to the late diastolic potential (LDP).BACKGROUNDWe showed that the slow conduction zone of ILVT could be divided into two components by LDP; that is, the distal component with a tachycardia-dependent conduction delay property and the proximal one without it.METHODSElectrophysiologic studies were performed in eight consecutive patients. The LDP was recorded during left ventricular (LV) mapping during ILVT. Entrainment was performed from the right ventricular outflow tract while recording LDP. The effects of lidocaine (1 mg/kg body weight) and verapamil (0.5 or 1.0 mg) were examined during entrainment.RESULTSThe LDPs preceding the Purkinje potential (PP) were serially recorded from the upper third to the middle of the LV septum along the narrow longitudinal line. The ventricular tachycardia (VT) cycle length increased after lidocaine (p < 0.05), and further after verapamil (p < 0.05). The increments in the VT cycle length after administration of the drugs strongly correlated with those in LDP-PP (r > 0.9 for both drugs). The interval from the ventricular potential to LDP was unchanged after administration of the drugs. In one patient, verapamil terminated VT by local conduction block between LDP and PP. The LDP-PP measured during entrainment increased after lidocaine, and further after verapamil, whereas the interval from the stimulus to LDP remained unchanged.CONCLUSIONSThe component distal to LDP is mainly calcium channel-dependent and partly depressed sodium channel-dependent. The proximal component is considered to be sodium channel-dependent (normal)
A Superflare on YZ Canis Minoris Observed by Seimei Telescope and TESS: Red Asymmetry of H Emission Associated with White-Light Emission
Active M-type stars are known to often produce superflares on the surface.
Radiation from stellar (super-)flares is important for the exoplanet
habitability, but the mechanisms are not well understood. In this paper, we
report simultaneous optical spectroscopic and photometric observations of a
stellar superflare on an active M dwarf YZ CMi with the 3.8-m Seimei telescope
and the . The flare bolometric
energy was and H energy
was . The H emission line
profile showed red asymmetry throughout the flare with a duration of . The velocity of the red asymmetry was and line width of H was broadened up to
. The redshifted velocity and line width of H line decayed more
rapidly than the equivalent width, and their time evolutions are correlated
with that of the white-light emission. This indicates a possibility that the
white light, H red asymmetry, and H line broadening originate
from nearly the same site, i.e., the dense chromospheric condensation region
heated by non-thermal electrons. On the other hand, the flux ratio of the
redshifted excess components to the central components is enhanced one hour
after the flare onset. This may be due to the change of the main source of the
red asymmetry to the post-flare loops in the later phase of the flare.Comment: 13 pages, 5 figures. Accepted for publication in The Astrophysical
Journa
Detection of a high-velocity prominence eruption leading to a CME associated with a superflare on the RS CVn-type star V1355 Orionis
Stellar coronal mass ejections (CMEs) have recently received much attention
for their impacts on exoplanets and stellar evolution. Detecting prominence
eruptions, the initial phase of CMEs, as the blue-shifted excess component of
Balmer lines is a technique to capture stellar CMEs. However, most of
prominence eruptions identified thus far have been slow and less than the
surface escape velocity. Therefore, whether these eruptions were developing
into CMEs remained unknown. In this study, we conducted simultaneous optical
photometric observations with Transiting Exoplanet Survey Satellite and optical
spectroscopic observations with the 3.8m Seimei Telescope for the RS CVn-type
star V1355 Orionis that frequently produces large-scale superflares. We
detected a superflare releasing . In the
early stage of this flare, a blue-shifted excess component of extending its velocity up to was
observed and thought to originate from prominence eruptions. The velocity
greatly exceeds the escape velocity (i.e., ), which provides important evidence that stellar prominence eruptions
can develop into CMEs. Furthermore, we found that the prominence is very
massive (). These data will clarify whether such events follow existing
theories and scaling laws on solar flares and CMEs even when the energy scale
far exceeds solar cases.Comment: 16 pages, 8 figures. Accepted for publication in The Astrophysical
Journa
DNA methylation detection based on difference of base content
Methylation frequently occurs in cytosines of CpG sites to regulate gene expression. The identification of aberrant methylation of certain genes is important for cancer marker analysis. The aim of this study was to determine the methylation frequency in DNA samples of unknown length and/or concentration. Unmethylated cytosine is known to be converted to thymine following bisulfite treatment and subsequent PCR. For this reason, the AT content in DNA increases with an increasing number of methylation sites. In this study, the fluorescein-carrying bis-acridinyl peptide (FKA) molecule was used for the detection of methylation frequency. FKA contains fluorescein and two acridine moieties, which together allow for the determination of the AT content of double-stranded DNA fragments. Methylated and unmethylated human genomes were subjected to bisulfide treatment and subsequent PCR using primers specific for the CFTR, CDH4, DBC1, and NPY genes. The AT content in the resulting PCR products was estimated by FKA, and AT content estimations were found to be in good agreement with those determined by DNA sequencing. This newly developed method may be useful for determining methylation frequencies of many PCR products by measuring the fluorescence in samples excited at two different wavelengths.India-Japan Expert Group Meeting on Biomolecular Electronics & Organic Nanotechnology for Environment Preservation (IJEGMBE 2015), 23–26 December, 2015, Fukuoka, Japa
Acute bout of exercise downregulates thioredoxin-interacting protein expression in rat contracting skeletal muscles
We previously reported that in rat skeletal muscle, disuse (i.e., decreased muscle contractile activity) rapidly increases thioredoxin-interacting protein (TXNIP), which is implicated in the reduced glucose uptake. Accordingly, we sought herein to (a) determine the effect of exercise (i.e., increased muscle contractile activity) on muscle TXNIP protein expression, and (b) elucidate the mechanisms underlying the changes of TXNIP protein expression in response to exercise. Rat epitrochlearis and soleus muscles were dissected out after an acute bout of 3-hr swimming (without weight loading) or 3-hr treadmill running (15% grade at 9m/min). In a separate protocol, the isolated epitrochlearis and soleus muscles were incubated for 3 hr with AMP-dependent protein kinase activator AICAR. Immediately after the cessation of the 3-hr swimming, the TXNIP protein was decreased in epitrochlearis but not in soleus muscle. Conversely, 3-hr treadmill running decreased the TXNIP protein in soleus but not in epitrochlearis muscle. TXNIP protein was decreased concomitantly with reduced postexercise muscle glycogen, showing that a decrease in TXNIP protein expression occurs in muscles that are recruited during exercise. In addition, 3-hr incubation with AICAR decreased TXNIP protein in both isolated epitrochlearis and soleus muscles. Our results suggest that (a) an acute bout of exercise downregulates TXNIP protein expression in rat contracting skeletal muscles, and (b) the reduction in TXNIP protein expression in contracting muscles is probably mediated by AMPK activation, at least in part
近年の大卒者の職業への移行過程 : 「高等教育と職業に関する日欧比較調査」より
日本教育社会学会第51回大会, 1999年(東京大学), 研究発表Ⅳ Ⅳ-5部会 経済と教育(2
On the Average Time- and Frequency-Pattern of Photic Flicker Response in Relation to Intrinsic Alpha Activity Verified by a New Simple Method
Delivering photic flicker stimulations from about 8 to 12 flashes per second for about 60 seconds continuously to relaxed normal adult human subject, the average properties of the driven EEG waves are obtained by applying a new practical crosscorrelation method to eliminate the irrelevant oscillations to the stimulation. The average time-pattern of the intrinsic alpha activity was carved in relief by a new simple autocorrelation method, which is originally demonstrated here. The EEGs are traced from the occipital, parietal, temporal and frontal regions by monopolar technique. Even immediately after the initiation of flicker stimulation, the response wave of the stimulating frequency was driven and tended to build up gradually to the maximum average intensity in the course of contiunal stimulation, especially in the occipital region, showing some fluctuation in size. The average distribution of the driven wave over the scalp was similar to those of the relaxed intrinsic alpha wave activity, in size and phase angle. From these evidences it would be assumed at least for the first approximation that the driven waves are produced from a generator essentially similar to what acts in relaxed state. In the occipital region, the EEG response was easily driven more intensely the intrinsic alpha activity in the relaxed state by a photic flicker stimulation with a higher frequency than that of relaxed alpha activity, whereas weaker response tended to be driven by lower frequency of stimulation. In other regions, however, a reverse tendency was observed immediately after the initiation of the stimulation
Improvement of acquisition and analysis methods in multi-electrode array experiments with iPS cell-derived cardiomyocytes
AbstractIntroductionMulti-electrode array (MEA) systems and human induced pluripotent stem (iPS) cell-derived cardiomyocytes are frequently used to characterize the electrophysiological effects of drug candidates for the prediction of QT prolongation and proarrhythmic potential. However, the optimal experimental conditions for obtaining reliable experimental data, such as high-pass filter (HPF) frequency and cell plating density, remain to be determined.MethodsExtracellular field potentials (FPs) were recorded from iPS cell-derived cardiomyocyte sheets by using the MED64 and MEA2100 multi-electrode array systems. Effects of HPF frequency (0.1 or 1Hz) on FP duration (FPD) were assessed in the presence and absence of moxifloxacin, terfenadine, and aspirin. The influence of cell density on FP characteristics recorded through a 0.1-Hz HPF was examined. The relationship between FP and action potential (AP) was elucidated by simultaneous recording of FP and AP using a membrane potential dye.ResultsMany of the FP waveforms recorded through a 1-Hz HPF were markedly deformed and appeared differentiated compared with those recorded through a 0.1-Hz HPF. The concentration–response curves for FPD in the presence of terfenadine reached a steady state at concentrations of 0.1 and 0.3μM when a 0.1-Hz HPF was used. In contrast, FPD decreased at a concentration of 0.3μM with a characteristic bell-shaped concentration–response curve when a 1-Hz HPF was used. The amplitude of the first and second peaks in the FP waveform increased with increasing cell plating density. The second peak of the FP waveform roughly coincided with AP signal at 50% repolarization, and the negative deflection at the second peak of the FP waveform in the presence of E-4031 corresponded to early afterdepolarization and triggered activity.DiscussionFP can be used to assess the QT prolongation and proarrhythmic potential of drug candidates; however, experimental conditions such as HPF frequency are important for obtaining reliable data
Exome sequencing of senescence-accelerated mice (SAM) reveals deleterious mutations in degenerative disease-causing genes
Background: Senescence-accelerated mice (SAM) are a series of mouse strains originally derived from unexpected crosses between AKR/J and unknown mice, from which phenotypically distinct senescence-prone (SAMP) and -resistant (SAMR) inbred strains were subsequently established. Although SAMP strains have been widely used for aging research focusing on their short life spans and various age-related phenotypes, such as immune dysfunction, osteoporosis, and brain atrophy, the responsible gene mutations have not yet been fully elucidated. Results: To identify mutations specific to SAMP strains, we performed whole exome sequencing of 6 SAMP and 3 SAMR strains. This analysis revealed 32,019 to 38,925 single-nucleotide variants in the coding region of each SAM strain. We detected Ogg1 p.R304W and Mbd4 p.D129N deleterious mutations in all 6 of the SAMP strains but not in the SAMR or AKR/J strains. Moreover, we extracted 31 SAMP-specific novel deleterious mutations. In all SAMP strains except SAMP8, we detected a p.R473W missense mutation in the Ldb3 gene, which has been associated with myofibrillar myopathy. In 3 SAMP strains (SAMP3, SAMP10, and SAMP11), we identified a p.R167C missense mutation in the Prx gene, in which mutations causing hereditary motor and sensory neuropathy (Dejerine-Sottas syndrome) have been identified. In SAMP6 we detected a p.S540fs frame-shift mutation in the Il4ra gene, a mutation potentially causative of ulcerative colitis and osteoporosis. Conclusions: Our data indicate that different combinations of mutations in disease-causing genes may be responsible for the various phenotypes of SAMP strains.ArticleBMC GENOMICS. 14:248 (2013)journal articl
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