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Snow- or ice-covered road detection in winter road surface conditions using deep neural networks
No full textTraffic accidents occur frequently in cold and snow- or ice-covered regions due to weather changes that occur during the winter season. To detect the snow- or ice-covered roads in road surface conditions, road surface images captured using fixed-point cameras installed along the route are sufficient. This paper proposes a snow- or ice-covered road detection method that uses the deep convolutional autoencoding Gaussian mixture model (DCAGMM) with structural similarity (SSIM). The DCAGMM method, which is an unsupervised anomaly detection method, is unaffected by imbalance in the training data. In addition, the end-to-end convolutional neural network implemented in the DCAGMM enables the capture of the unique characteristics of the road surface images. Finally, by reconstructing the input images as normal images, the comparison of the input and reconstructed images enables identification of snow- or ice-covered road areas without requiring pixel-level annotations. Furthermore, the road surface images include complex characteristics for reconstruction, and the SSIM-based reconstruction error allows us to preserve the image quality of the reconstructed image. Experimental results obtained on real-world road surface images demonstrate the effectiveness of the proposed method
Long-term observation of the Soya Warm Current using HF ocean radars: relationship between the Soya Warm Current variability and the sea level anomalies in the Soya/La Perouse Strait
No full textThree high-frequency (HF) ocean radars were installed at the Soya/La Perouse Strait to monitor the surface current fields of the Soya Warm Current (SWC), which flows through the strait from the Sea of Japan to the Sea of Okhotsk. These ocean radars were operated for 19 years, from August 2003 to March 2022. In this paper, seasonal to interannual variations in the SWC were investigated using surface current fields obtained by the HF ocean radars combined with coastal tide gauge records and sea level anomaly from satellite altimetry. The HF ocean radars clearly captured the seasonal and interannual variations in the SWC. The alongshore surface velocity of SWC showed a high correlation with the alongshore sea level difference (SLD) between the Sea of Japan and the Sea of Okhotsk if seasonal variations were included. However, anomalies of the SLD and SWC alongshore velocity exhibited a lower correlation, especially in summer. This suggests that different mechanisms may be involved in summer and winter. The alongshore SLD between Wakkanai and Abashiri, which has been utilized in previous studies as an indicator of SWC intensity, may not be appropriate for representing interannual variations in the SWC intensity in summer, when the SWC reaches the maximum current velocity. Instead, it was demonstrated that the offshore SLD anomaly estimated using satellite altimetry with the coastal tide gauge record at Wakkanai could be a better index for representing the interannual variations throughout the year
Static attitude stability of deep space sample return capsule with thin aeroshell
No full textA sample return mission to deep space has been proposed. The orbital velocity of the deep space sample return capsule (DS-SRC) during atmospheric entry reaches 15 km/s, which results in extremely severe aerodynamic heating to the sample return capsule. We proposed a new concept of the DS-SRC with a lightweight and large-area aeroshell to reduce the severe heating environment at high altitudes through efficient aero-deceleration. The DS-SRC must be aerodynamically stable at all speeds because it is expected to be operated without a parachute at atmospheric entry. First, we showed the flight environment of the DS-SRC along the atmospheric entry trajectory obtained by trajectory analysis. Second, we investigated the aerodynamic characteristics and the static stability in the all-speed range using low-speed, transonic, and supersonic wind tunnels. Last, we used a computational science approach to conduct unsteady turbulent flow simulations to show its stability mechanism. The trajectory analysis indicated that the peak heat flux at the stagnation point of the capsule was kept approximately 10 MW/m2 when decelerating from high altitude because of its low ballistic coefficient. Based on the wind tunnel experimental results, we confirmed that this capsule is statically stable in attitude at all speeds. Furthermore, the computed results suggested that there is a difference in pressures at the windward and leeward sides of the front surface when the capsule is pitched up or down. This difference in pressure distribution acts as a static stability mechanism generating a moment in the direction that restores the pitching motion
ソフトフード摂取が唾液腺に及ぼす影響に関する形態学的解析
No full text現代日本では軟らかい食べ物、いわゆるソフトフードが好まれる傾向がある。著者らはこのような食習慣が唾液腺にどのような影響を与えるのかについて形態学的に解析してきた。動物をソフトフードとして液状飼料を用いて飼育すると耳下腺は萎縮し、組織学的には腺房細胞の縮小、アポトーシスの増加、増殖活性の低下が認められた。成長期の動物を同様に飼育すると耳下腺の発育は抑制された。一方で、顎下腺、舌下腺、口蓋腺では耳下腺に認められるような影響はほとんどみられなかった。このようにソフトフードに対する反応は唾液腺の種類によって異なっていることが明らかとなったが、なぜこのような相違が生じるのかについても本稿では考察を加えてみたい。Modern people tend to prefer soft food, and it is a clinical concern that such eating habits may have unfavorable influences on the oral tissues. Therefore, the authors have been focusing on salivary glands and morphologically investigating the effects of soft food on them.In rats fed a liquid diet, parotid gland weight reduced, and shrinkage of acinar cells was histologically observed. Apoptotic acinar cells were commonly identified by transmission electron microscopy, and proliferative activity of acinar cells decreased, indicating that acinar cells reduced in number in the atrophic parotid glands. In growing rats fed a liquid diet after weaning, the growth of parotid glands was inhibited. However, there were no or extremely slight influences of liquid diet feeding on other salivary glands such as submandibular, sublingual, and palatine glands. The above observations show that soft food negatively affects parotid glands much more than other salivary glands. The authors would like to discuss why the response of parotid glands to soft food is different from other salivary glands in this review
Foehn winds influence surface ablation on Glaciar Perito Moreno, southern Patagonian icefield
No full textThe southern Patagonian glaciers are known for having extremely high ablation rates. Foehn winds are one of the suspected causes, however, their influence on the annual ablation, their interannual variations, and their relationship with climate change is not well understood. We analysed the in-situ meteorological data from 2003–2020 recorded at Glaciar Perito Moreno. Daily temperature lapse rates varied substantially, from −7.8°C km−1 to 10.4°C km−1, due to foehn, fog, and katabatic winds. We find that, on average, foehn events occurred 1073 hours per year, and accounted for 20% of the annual surface ablation. This increase in surface ablation rates during foehn events occurs as a result of the enhanced sensible heat flux and net shortwave radiation. The downglacier-directed foehn winds warm the air mass over the glacier, but because of the high humidity of the foehn here, they often release latent heat by condensation. Variations in the Amundsen Sea Low influence foehn occurrence by modulating the westerly winds, which is related to the hemispherical ocean and atmospheric variability. Our results show that the local climate play an important role in the surface melting of Patagonian glaciers
Study of lymphatic drainage patterns of malignant skin tumors in the head and neck region
No full text配架番号：284
Effects of recombinant osteopontin expressed in Escherichia coli on the recovery of the endometrial epidermal growth factor profile and fertility in repeat breeder dairy cows
No full textEndometrial epidermal growth factor (EGF) shows a cyclic change with two peaks on days 2-4 and days 13-14 of the estrous cycle. In repeat breeder cows, loss of the peaks has been associated with reduced fertility. By infusing seminal plasma (SP) and osteopontin (OPN) derived from SP and milk into the vagina, their EGF profile and fertility are restored. However, SP is difficult to obtain, and both SP and OPN can transmit infectious diseases. While OPN can be sourced from recombinant protein without this risk, recombinant bovine OPN (rOPN) expressed in Escherichia coli should be examined for its effects on the EGF profile, since it does not undergo posttranslational modification, which is important for its biological activity. In study 1, PBS, SP (0.5 mL), and rOPN (0.3 mg) were infused into the vagina at estrus (day 0) in 74, 37, and 105 repeat breeder Holstein cows, respectively, with an altered EGF profile. The endometrial EGF concentrations were measured on day 3. Some cows (n = 58, 20, and 83, respectively) were inseminated immediately before the infusion and then diagnosed for pregnancy between days 30 and 35. The normalization rate of the EGF profile and conception rate in the rOPN group (58.1 % and 47.0 %, respectively) were not significantly different from those in the SP group (62.2 % and 45.0 %, respectively) but higher than those in PBS group (29.7 % and 28.1 %, respectively) (P < 0.05). In study 2, repeat breeder cows with an altered EGF profile were infused with PBS (n = 18) and rOPN (n = 17), while fertile controls with a normal EGF profile (n = 18) were infused with PBS. Two or three embryos were transferred into cows on day 7 and then recovered on day 14. Embryo recovery rates of the rOPN and fertile groups were comparable (58.7 % vs. 58.3 %) but higher than that of the PBS group (58.7 % vs. 32.0 %) (P < 0.05). The embryo recovery rate of cows with normalized EGF profile was higher than that of cows with unnormalized EGF profile (64.4 % vs. 16.7 %) (P < 0.05). The embryo sizes of cows in the rOPN and fertile groups were comparable but larger than those in the PBS group (P < 0.05). However, the embryo size was not correlated to the corresponding endometrial EGF concentrations. In conclusion, rOPN without posttranslational modifications normalized the EGF profile in repeat breeder cows. Improved fertility by normalization of the EGF profile could be attributed partly to the increased embryo viability up to day 14
Photoinduced Platinum-Catalyzed Reductive Allylation of α-Diketones with Allylic Carbonates
No full textA unique process for the photoinduced platinum-catalyzed reductive allylation of alpha-diketones with allylic carbonates has been developed. This allylation reaction was found to proceed selectively at the more electron-deficient carbonyl group of the diketone to afford an alpha-keto homoallylic alcohol. Such products could be further derivatized by transformation of the remaining carbonyl group. A mechanistic investigation suggests that a ketyl radical generated in response to photoirradiation reacts with a (pi-allyl)platinum complex to form a C-C bond