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Paint protects the outer surface of ships. The antifouling component of paint prevents aquatic organisms from attaching to the surface of the ship. However, marine paints deteriorate with time. Therefore, periodic repainting is required. Repainting is performed via sandblasting, in which an abrasive is sprayed onto the surface of the paint. However, in this method, the base material of the paint is damaged. According to previous studies, when a painted surface is irradiated by plasma, the paint tends to peel off easily. Herein, we hypothesize that the paint is easily peeled off because of the thermal stress induced by the plasma during irradiation. To verify this hypothesis, we experimentally investigated the effect of thermal stress due to atmospheric pressure plasma. Results show that the streamer is a factor that easily peels off the paint. In addition, the effect of thermal stress due to the crosslinking reaction was confirmed via plasma irradiation. Furthermore, the effect of chipping due to intermittent discharge was explored by observing the painted surface via SEM.

Mexoryl SX (terephthalylidene-3,3′-dicamphor-10,10′-disulfonic acid, Ecamsule) is a water-soluble UV-A absorber. The near-IR phosphorescence spectrum of singlet oxygen generated by photosensitization with Mexoryl SX was not observed in air-saturated water. On the other hand, the time-resolved near-IR phosphorescence spectrum was observed in oxygen-saturated phosphate buffer (pH 7.4). The quantum yield of the singlet oxygen generation (ΦΔ) was determined to be 0.0021 ± 0.0005. The ability of Mexoryl SX as a photosensitizer is quite low. The question arises as to the quite low ΦΔ value. No phosphorescence was detectable from Mexoryl SX in ethanol at 77 K. We elucidated the nature of the lowest excited triplet (T1) state of Mexoryl SX using a time-resolved EPR technique, because this technique is powerful for the study of short-lived and nonphosphorescent T1 molecules. The strong time-resolved EPR signals were observed. This fact shows that a considerable proportion of the lowest excited singlet (S1) state molecules undergoes intersystem crossing (ISC) to the T1 state and the deactivation process of the T1 state is mainly radiationless. The observed zero-filed splitting parameters, T1 lifetime, and S1 → T1 ISC anisotropy suggest that the T1 state can be regarded as a 3nπ*–3ππ* mixing state in character and the two unpaired electrons in the T1 state do not localize on (4-methylbenzylidene)camphor, a closely related component. Although the shorter T1 lifetime (47 ns) prevents T1 state quenching by ground-state oxygen, the 3nπ* character may contribute something to the low ΦΔ value.

When humans write, they may unintentionally omit some information. Complementing the omitted information using a computer is helpful in providing writing support. Recently, in the field of story understanding and generation, story completion (SC) was proposed to generate the missing parts of an incomplete story. Although its applicability is limited because it requires that the user have prior knowledge of the missing part of a story, missing position prediction (MPP) can be used to compensate for this problem. MPP aims to predict the position of the missing part, but the prerequisite knowledge that "one sentence is missing" is still required. In this study, we propose Variable Number MPP (VN-MPP), a new MPP task that removes this restriction; that is, the task to predict multiple missing sentences or to judge whether there are no missing sentences in the first place. We also propose two methods for this new MPP task. Furthermore, based on the novel task and methods, we developed a creative writing support system, COMPASS. The results of a user experiment involving professional creators who write texts in Japanese confirm the efficacy and utility of the developed system., Comment: 32 pages, 12 Figures

Some mouse models of Down syndrome (DS), including Ts1Cje mice, exhibit impaired prenatal neurogenesis with yet unknown molecular mechanism. To gain insights into the impaired neurogenesis, a transcriptomic and flow cytometry analysis of E14.5 Ts1Cje embryo brain was performed. Our analysis revealed that the neutrophil and monocyte ratios in the CD45‐positive hematopoietic cells were relatively increased, in agreement with the altered expression of inflammation/immune‐related genes, in Ts1Cje embryonic brain, whereas the relative number of brain macrophages was decreased in comparison to wild‐type mice. Similar upregulation of inflammation‐associated mRNAs was observed in other DS mouse models, with variable trisomic region lengths. We used genetic manipulation to assess the contribution of Erg, a trisomic gene in these DS models, known to regulation hemato‐immune cells. The perturbed proportions of immune cells in Ts1Cje mouse brain were restored in Ts1Cje‐Erg(+/+/Mld2) mice, which are disomic for functional Erg but otherwise trisomic on a Ts1Cje background. Moreover, the embryonic neurogenesis defects observed in Ts1Cje cortex were reduced in Ts1Cje‐Erg(+/+/Mld2) embryos. Our findings suggest that Erg gene triplication contributes to the dysregulation of the homeostatic proportion of the populations of immune cells in the embryonic brain and decreased prenatal cortical neurogenesis in the prenatal brain with DS.

Riboflavin (RF), a water-soluble vitamin B2, is an endogenous singlet oxygen photosensitizer in human skin and eye. Time profiles of the near-infrared phosphorescence of singlet oxygen generated by RF have been measured in the absence and presence of l-ascorbic acid (AA, vitamin C), 3-O-ethyl-l-ascorbic acid (3-EtAA) and Trolox (TX, a water-soluble analogue of vitamin E) in phosphate buffer (pH 6.8). These substances suppress the RF-photosensitized singlet oxygen generation. For example, the quantum yield of singlet oxygen generation is decreased to a third by adding 0.4 mmol dm^(−3) AA or TX (the concentration of dissolved oxygen in air-saturated water is 0.27 mmol dm^(−3)). AA and TX are more efficient suppressors of RF-photosensitized singlet oxygen generation than 3-EtAA. The bimolecular rate constants for quenching of the excited singlet and triplet states of RF by AA, 3-EtAA and TX have been determined through measurements of fluorescence and transient absorption. These measurements suggest that the observed suppression is due to the quenching of the excited singlet and triplet states of RF by AA, 3-EtAA and TX. The bimolecular rate constants for quenching of singlet oxygen by AA, 3-EtAA and TX were determined to be 1.8 × 10^8, 0.27 × 10^8, and 4.4 × 10^8 mol^(−1) dm^3 s^(−1), respectively.

Diethylhexyl 2,6-naphthalate (DEHN, tradename Corapan TQ) is used as a photostabilizer for a widely-used UV-A absorber, butylmethoxydibenzoylmethane (BMDBM). The photophysical properties of DEHN have been studied through measurements of the transient absorption, fluorescence, phosphorescence and EPR spectra in ethanol. The energy level of the lowest excited singlet state of DEHN is higher than that of BMDBM (enol form). The singlet-singlet energy transfer from BMDBM to DEHN is energetically unfavourable. The energy level of the lowest excited triplet (T1) state of DEHN is lower than that of BMDBM. It is probable that the mechanism of photostabilization of BMDBM by DEHN is the triplet-triplet energy transfer from BMDBM to DEHN. The observed phosphorescence spectrum, T1 lifetime and zero-field splitting parameters indicate that the T1 state of DEHN can be regarded mainly as a locally excited 3ππ* state within naphthalene. The sum of the quantum yields of fluorescence of DEHN (0.59 ± 0.09) and singlet oxygen generation by DEHN (0.44 ± 0.04) is almost unity in ethanol. About 60% of the UV energy absorbed by DEHN is released as fluorescence, while about 40% is used to produce the excited triplet state. The photoexcited states of 2-naphthoic acid have been studied for comparison.

Cross-coupling of alkyl halides with alkyl Grignard reagents proceeds with extremely high TONs of up to 1230000 using a Cu/unsaturated hydrocarbon catalytic system. Alkyl fluorides, chlorides, bromides, and tosylates are all suitable electrophiles, and a TOF as high as 31200 h(-1) was attained using an alkyl iodide. Side reactions of this catalytic system, i.e., reduction, dehydrohalogenation (elimination), and the homocoupling of alkyl halides, occur in the absence of additives. It appears that the reaction involves the β-hydrogen elimination of alkylcopper intermediates, giving rise to olefins and Cu-H species, and that this process triggers both side reactions and the degradation of the Cu catalyst. The formed Cu-H promotes the reduction of alkyl halides to give alkanes and Cu-X or the generation of Cu(0), probably by disproportionation, which can oxidatively add to alkyl halides to yield olefins and, in some cases, homocoupling products. Unsaturated hydrocarbon additives such as 1,3-butadiene and phenylpropyne play important roles in achieving highly efficient cross-coupling by suppressing β-hydrogen elimination, which inhibits both the degradation of the Cu catalyst and undesirable side reactions.

Quantitative analysis was tried for cognitive functions for 115 volunteers, aged 21 to 88 years. Reaction time (RT) was used for visual (V-RT), auditory (A-RT), vibratory cues (V-RT), right-left-orientation cognition (RL-RT), and short-term-memory cognition (STM-RT) for the same subjects. Subjects were asked to judge a cue presented whether the right or left side and push a button at the same side as the cue presented, as for V-RT, A-RT, and V-RT. Subjects were asked to read sentences as “Push the right/left button, or Push the same button as the previous instruction" and RTs were measured for the former sentence as for RL-RT, and the latter sentences for STM-RT. RTs were analyzed with the exponential regression, and all RTs increased with increasing age significantly. Mean RT and standard deviation was 0.48±0.17sec for V-RT, 0.44±0.28sec for A-RT, 0.51±0.20sec for V-RT, 9.12±4.01sec for RL-RT, and 5.26±2.45sec for STM-RT. The analysis of variance showed significant among RTs (P

The aim of this study was to develop a novel quantitative method for examining the cube copying test. The analysis has been only through qualitative observation for the test. Therefore we applied a quantitative method to analyze cube copying test results. Figures were digitized and their symmetry was studied to determine correlation coefficients (CCs). This study included 19 elderly subjects (68-92 years) who complained of memory disturbance or being afraid of dementia, and 9 younger subjects (21-60 years) who visited our hospital with minor head trauma or dizziness. Six CCs were examined between the sample and drawn figures, between the drawn figure and 180°-rotated drawn figure, between the left half and right half of the drawn figure, between the upper half and lower half of the drawn figure, between a quadrant and an opposite 180°-rotated quadrant of the drawn figure. All CCs were significantly low for the elderly group. The elderly group also showed mild deterioration in the Hasegawa's Dementia Scale (21. 1/30) and CT findings with cortical and/or ventricular dilatation and lacunae. No neurological deficit was noted for the younger group. Our quantitative method may be useful for evaluating not only constructional apraxia but also dementia and mild cognitive impairment.

It has been suggested that the maturational stage of oocytes at time of insemination influences the sex ratio of resulting embryos. However, there are very few reports concerning the relationship between the maturation culture period of oocytes and the sex ratio of resulting embryos. The objective of this study was to investigate the effects of in vitro maturation culture period for bovine oocytes on the sex ratio of in vitro produced blastocysts using a novel technique of loop-mediated isothermal amplification (LAMP). Cumulus-oocyte complexes were collected from the ovaries of slaughtered cows, and then matured in vitro for various periods (16, 22, 28, and 34 h). After maturation culture for each period, the oocytes were inseminated with frozen-thawed spermatozoa, and then cultured in vitro. Blastocysts were harvested on Day 7 after insemination, and the sex of the embryos was examined using the LAMP method. The rates of oocytes matured to the metaphase II stage were significantly lower (P < 0.05) in the 16-h maturation group than in the other groups. The proportion of blastocyst formation after insemination was significantly higher (P < 0.05) in the 22-h maturation group than in the other groups. The proportion of male blastocysts increased with the increase in maturation culture period. The proportion of male blastocysts derived from oocytes matured for 34 h was significantly higher (P < 0.05) than from oocytes matured for 16 and 22 h. These results indicate that the sex ratio of in vitro fertilized embryos is apparently influenced by the maturation culture period of the oocytes.

Introduction Visual attention enhances our perception and even alters the perception of figures, as we often see in ambiguous figures. We investigated computationally the role of spatial attention in early vision for the perception of direction-offigure (DOF). Spatial attention alters local contrast gain in early vision, thus apparent local contrast will be modulated. If the local contrast is the basis for the determination of border-ownership (BO) that tells which side of a contour owns the border [1,2], BO will be modulated based on the local contrast that is altered by the attention. If the effect of attention is significant, the activity of BOselective cells will be facilitated/suppressed so that the DOF will be flipped.

Spatial attention alters contrast gain in early visual areas, which might affect the determination of border ownership (BO)that indicates the direction of figure with respect to the border. We investigated the role of spatial attention applied to earlyvision in the determination of BO with a computational model that consists of V1, V2, and posterior parietal (PP) modules.Attention alters contrast gain in the V1 module so that it enhances local contrast. The V2 module determines BO based onthe surrounding contrast extracted by the V1 module. The simulation results showed that the attention significantlymodulates BO; BO is even flipped in figures with ambiguous BO while BO is stable for unambiguous figures such as asimple square. To evaluate the model quantitatively, we carried out psychophysical experiments to measure the effects ofattention in the perception of BO and compared the results with those from corresponding simulations. The model showedgood agreement with human perception including the determination of BO for ambiguous random-block stimuli. Theseresults indicate that the activity of BO-selective neurons could be modulated significantly by spatial attention that alters localcontrast gain in V1, which may account in part for automatic, bi-stable perception in ambiguous figures.Keywords: attention, border ownership, early vision, computational model, surrounding modulationCitation: Wagatsuma, N., Shimizu, R., & Sakai, K. (2008). Spatial attention in early vision for the perception of borderownership. Journal of Vision, 8(7):22, 1–19, http://journalofvision.org/8/7/22/, doi:10.1167/8.7.22.

We conducted two experiments to investigate the effects of storage temperature and period for cat ovaries on the meiotic and developmental competence of oocytes collected from the ovaries. In Experiment 1, ovaries were stored in physiological saline for 24 h at 4 C, 23-25 C, or 38 C (cold, room, and incubator temperature groups, respectively), and then oocytes were collected from the ovaries in each group. Morphologically intact oocytes were then selected and cultured in maturation medium for 24 h. Significantly more oocytes reached metaphase II (MII) in the cold temperature group (53.4%) than in the room and incubator temperature groups (20.0 and 2.4%, respectively). In Experiment 2, ovaries were stored in physiological saline at room temperature for 0, 6, 12 or 18 h, and then they were stored at 4 C (cold storage) until reaching a total storage period of 24 h. After storage of the ovaries, morphologically intact oocytes were matured, fertilized with frozen-thawed spermatozoa, and cultured in vitro. The rates of morphologically intact oocytes obtained from the ovaries stored at room temperature for 0, 6, 12 or 18 h were 35.3, 30.0, 26.4 and 14.7%, respectively, and the rates of intact oocytes that reached MII were 63.2, 36.4, 26.5 and 11.9%, respectively. The results suggested that the numbers of morphologically intact oocytes and intact oocytes that reached MII after in vitro maturation decrease gradually as the period of storage at room temperature before cold storage increases. Only oocytes from ovaries stored for 6 h developed to the blastocyst stage after in vitro maturation and fertilization when ovaries were stored at room temperature before cold storage. These results indicate that 24 h storage of ovaries at high temperatures (>23 C) decreases the meiotic competence of oocytes. The quality and developmental competence of oocytes are influenced by the length of storage at room temperature before cold storage.

2020年度