A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome

An animal-like cryptochrome derived from Chlamydomonas reinhardtii (CraCRY) is a bifunctional flavoenzyme harboring flavin adenine dinucleotide (FAD) as a photoreceptive/catalytic center and functions both in the regulation of gene transcription and the repair of UV-induced DNA lesions in a light-dependent manner, using different FAD redox states. To address how CraCRY stabilizes the physiologically relevant redox state of FAD, we investigated the thermodynamic and kinetic stability of the two-electron reduced anionic FAD state (FADH−) in CraCRY and related (6–4) photolyases. The thermodynamic stability of FADH− remained almost the same compared to that of all tested proteins. However, the kinetic stability of FADH− varied remarkably depending on the local structure of the secondary pocket, where an auxiliary chromophore, 8-hydroxy-7,8-didemethyl-5-deazariboflavin (8-HDF), can be accommodated. The observed effect of 8-HDF uptake on the enhancement of the kinetic stability of FADH− suggests an essential role of 8-HDF in the bifunctionality of CraCRY.Hosokawa Y., Morita H., Nakamura M., et al. A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome. Scientific Reports 13, 16682 (2023); https://doi.org/10.1038/s41598-023-43930-0

Decreased Prostaglandin E2 Production by Inflammatory Cytokine and Lower Expression of EP2 Receptor Result in Increased Collagen Synthesis in Keloid Fibroblasts

We investigated the metabolism of arachidonic acid in normal skin-derived fibroblasts (NF) as well as in keloid-derived fibroblasts (KF) in response to macrophage migration inhibitory factor (MIF), a pluripotent cytokine. We found that MIF enhanced cyclooxygenase-2 activity in NF more than in KF. Consistent with this finding, prostaglandin E2 (PGE2), an antifibrogenic molecule, was more significantly increased in NF than in KF by MIF treatment. As regarding E prostanoid receptor 2, the level of expression was significantly lower in KF than in NF. On the other hand, Forskolin, a direct activator of adenylcyclase, decreased collagen synthesis in both NF and KF, which indicates that cAMP plays an important role in regulating collagen synthesis. As PGE2 induces cAMP production, it is conceivable that increased collagen synthesis in KF might be owing to decreased PGE2 and cAMP production. These findings may aid in the development of a therapeutic strategy for the regulation of collagen synthesis in keloid fibroblasts

CGMにおけるサイバーパトロールシステムの開発に関する研究 [論文要旨及び審査の要旨]

関西大

A Study on the Applicability of the Lesamnta-LW Lightweight Hash Function to TPMS

The Tire Pressure Monitoring System (TPMS) is used to monitor the pressure of the tires and to inform the driver of it. This equipment is mandatory for vehicles in US and EU. To ensure the security of TPMS, it is important to reduce the cost of the cryptographic mechanisms implemented in resourced-constrained devices. To address this problem, previous work has proposed countermeasures employing lightweight block ciphers such as PRESENT, SPECK, or KATAN. However, it is not clear to us that any of these works have addressed the issues of software optimization that considers TPMS-packet protection as well as session key updates for architectures consisting of the vehicle TPMS ECU and four low-cost TPM sensors equipped with the tires. In this paper, we propose to application of the ISO/IEC 29192-5 lightweight hash function Lesamnta-LW to address this issue. Our approach is to apply the known method of converting Lesamnta-LW to multiple independent pseudo-random functions (PRFs) in TPMS. In our case, we generate five PRFs this way and then use one PRF for MAC-generation and four for key derivation. Although we follow the NIST SP 800-108 framework of converting PRFs to key derivation functions, we confirm the significant advantage of Lesamnta-LW-based PRFs over HMAC-SHA-256 by evaluating the performance on AVR 8-bit micro-controllers, on which we consider simulating TPMS sensors. We expect that our method to achieve multiple-purposes with a single cryptographic primitive will help to reduce the total implementation cost required for TPMS security

Research Concerning Development of Cyber Patrol System in CGM

関西大

Performance Evaluation of NIST LWC Finalists on AVR ATmega and ARM Cortex-M3 Microcontrollers

This paper presents results of performance evaluation of NIST Lightweight Cryptography standardization finalists which are implemented by us. Our implementation method puts on the target to reduce RAM consumption on embedded devices. Our target microcontrollers are AVR ATmega 128 and ARM Cortex-M3. We apply our implementation method to five AEAD schemes which include four finalists of the NIST lightweight cryptography standardization and demonstrate the performance evaluation on target microcontrollers. From our performance evaluation of the RAM size, we have achieved 117-byte TinyJAMBU-128 on ATmega 128 and 140-byte TinyJAMBU-128 on ARM Cortex-M3. Our implementation of TinyJAMBU-128 has the smallest RAM of all the target AEAD schemes

Isotopic analysis of Ni, Cu, and Zn in freshwater for source identification

Nickel (Ni), copper (Cu), and zinc (Zn) are commonly used in human activities and pollute aquatic environments including rivers and oceans. Recently, Ni, Cu, and Zn isotope ratios have been measured to identify their sources and cycles in environments. We precisely determined the Ni, Cu, and Zn isotope ratios in rain, snow, and rime collected from Uji City and Mt. Kajigamori in Japan, and investigated the potential of isotopic ratios as tracers of anthropogenic materials. The isotope and elemental ratios suggested that road dust is the main source of Cu in most rain, snow, and rime samples and that some of the Cu may originate from fossil fuel combustion. Zinc in the rain, snow, and rime samples may be partially attributed to Zn in road dust. Zinc isotope ratios in the Uji rain samples are lower than those in the road dust, which would be emitted via high temperature processes. Nickel isotope ratios are correlated with V/Ni ratios in the rain, snow, and rime samples, suggesting that their main source is heavy oil combustion. Furthermore, we analyzed water samples from the Uji and Tawara Rivers and the Kakita River spring in Japan. Nickel and Cu isotope ratios in the river water samples were significantly heavier than those in rain, snow, and rime samples, while Zn isotope ratios were similar. This is attributed to isotopic fractionation of Cu and Ni between particulate-dissolved phases in river water or soil

シコク ノ カジガモリ サンチョウ ニオケル ジュヒョウ コウセツ トウキ コウウチュウ ノ リュウシジョウ ブッシツ ト コクショク フユウセイ ブッシツ

The wet-depositions of rime, fresh snow and winter rain fall were collected on the summit of Mt. Kajigamori (ALT. 1400m), where is the watershed protection forest of Riv. Yoshinogawa. The insoluble particulate matter included in the wet-deposition was obtained by filtration with 0.45μm pore-sized filter. Small spherical particles such as flyash were found in the residue by SEM-EDX analysis. The amount of residue was increasing in the order of rain< snow< rime, and was influenced by the back trajectory of air mass. The suspended particulate matter such as black belt was able to observe above Shikoku Island, Japan

Analysis of Chemical Species of Water-Insoluble Sulfur Compounds in Rime Ice and Snow and Long-range Transfer Mechanism of Coal Burning Emissions under Winter Monsoon Conditions

　樹氷と雪の中の非水溶性イオウ化合物の化学形態別分析と東アジアの石炭燃焼排出物の冬期モンスーン下での長距離輸送機構の同定法についてまとめた．単一分光結晶を用いた波長分散型蛍光エックス線装置による樹氷や雪の濾過物であるメンブレンフィルター上の薄膜分析を行った．S-Kα 線の化学シフトからイオウの化学状態別分析が可能であった．樹氷と雪の試料に限ってはカルシウム濃度とイオウ濃度からも化学状態分析が可能であった．卓上型の低真空走査電子顕微境エネルギー分散型X 線分光法（SEM-EDX）を用いて濾過薄膜中の無機小球体粒子（主に石炭フライアッシュ）の一粒子分析を行った．レーダーチャートパターンから5 種類のカテゴリーが見つかり，かつ，24 h 後方流跡線から発生域を中国華北，北東中国，朝鮮半島，黒竜江省－ロシア沿海地方，および日本を発生域に特定することを提案した．溶存成分中のCd，Pb，非海塩性硫酸イオンのモル比からそれらの発生域を特定できることもわかった．これらは，中国炭のイオウ同位体比，日本における鉛同位体比からの地域分けと一致した．We have conducted the analysis of chemical species of water-insoluble sulfur compounds in rime ice and snow and used the analysis to propose a long-range transport mechanism for coal-burning emissions in East Asia under winter monsoon conditions. Thin films of insoluble substances included in rime ice and snow on a 0.45 μm pore size membrane filter were analyzed by wavelength-dispersive X-ray fluorescence spectrometry with single dispersive crystal. Using this approach, we could analyze the sulfur-containing chemical species by examining the chemical shift of the S-Kα line. The chemical species containing sulfur were analyzed exclusively from the Ca and S concentrations in the residues of rime ice and snow. Single-particle analysis of the thin film on the membrane filter was performed for particles with size below 3 μm using a tabletop low-vacuum scanning electron microscopy with energy dispersive X-ray spectroscopy instrument. Particles were classified into six categories according to their compositions. Five major categories of spider chart distribution patterns were identified, and we proposed that they depended on the 24-hour back trajectory, such as Huabei, China, Northeast China, Korea Peninsula, Heilongjiang-Russia, and Japan types. We could assign the generating area of the air pollutants using the mole ratios of water-soluble Cd, Pb, and nss-SO42−species. These categories corresponded with the areas in China based on the isotope ratio of sulfur in Chinese coal and the isotope ratio of Pb collected in Japan

Detection of vegetation drying signals using diurnal variation of land surface temperature: Application to the 2018 East Asia heatwave

Satellite-based vegetation monitoring provides important insights regarding spatiotemporal variations in vegetation growth from a regional to continental scale. Most current vegetation monitoring methodologies rely on spectral vegetation indices (VIs) observed by polar-orbiting satellites, which provide one or a few observations per day. This study proposes a new methodology based on diurnal changes in land surface temperatures (LSTs) using Japan's geostationary satellite, Himawari-8/Advanced Himawari Imager (AHI). AHI thermal infrared observation provides LSTs at 10-min frequencies and ∼ 2 km spatial resolution. The DTC parameters that summarize the diurnal cycle waveform were obtained by fitting a diurnal temperature cycle (DTC) model to the time-series LST information for each day. To clarify the applicability of DTC parameters in detecting vegetation drying under humid climates, DTC parameters from in situ LSTs observed at vegetation sites, as well as those from Himawari-8 LSTs, were evaluated for East Asia. Utilizing the record-breaking heat wave that occurred in East Asia in 2018 as a case study, the anomalies of DTC parameters from the Himawari-8 LSTs were compared with the drying signals indicated by VIs, latent heat fluxes (LE), and surface soil moisture (SM). The results of site-based and satellite-based analyses revealed that DTR (diurnal temperature range) correlates with the evaporative fraction (EF) and SM, whereas Tmax (daily maximum LST) correlates with LE and VIs. Regarding other temperature-related parameters, T0 (LST around sunrise), Ta (temperature rise during daytime), and δT (temperature fall during nighttime) are unstable in quantification by DTC model. Moreover, time-related parameters, such as tm (time reaching Tmax), are more sensitive to topographic slope and geometric conditions than surface thermal properties at humid sites in East Asia, although they correlate with EF and SM at a semi-arid site in Australia. Additionally, the spatial distribution of the DTR anomaly during the 2018 heat wave corresponds with the drying signals indicated as negative SM anomalies. Regions with large positive anomalies in Tmax and DTR correspond to area with visible damage to vegetation, as indicated by negative VI anomalies. Hence, combined Tmax and DTR potentially detects vegetation drying indetectable by VIs, thereby providing earlier and more detailed vegetation monitoring in both humid and semi-arid climates