Why does arterial blood pressure rise actively during REM sleep?

A large fluctuation in autonomic function is one of the most important charac-teristics of REM sleep. Arterial blood pressure (AP) increases during the transition from non-REM to REM sleep, showing phasic surges during REM sleep. REM-associated AP changes involve 1) a long-term recovery process after surgery, 2) circadian rhythm, 3)relationships with ambient temperature. REM-associated AP changes are mediated by sympathetic nerves, buffered by baroreflex, abolished in decerebrated cats, and related to hippocampal theta activity in rats. Furthermore, the midbrain dopaminergic system has been recently found to be involved in increases in REM-associated AP

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

Compression by Substring Enumeration Using Sorted Contingency Tables

This paper proposes two variants of improved Compression by Substring Enumeration (CSE) with a finite alphabet. In previous studies on CSE, an encoder utilizes inequalities which evaluate the number of occurrences of a substring or a minimal forbidden word (MFW) to be encoded. The inequalities are derived from a contingency table including the number of occurrences of a substring or an MFW. Moreover, codeword length of a substring and an MFW grows with the difference between the upper and lower bounds deduced from the inequalities, however the lower bound is not tight. Therefore, we derive a new tight lower bound based on the contingency table and consequently propose a new CSE algorithm using the new inequality. We also propose a new encoding order of substrings and MFWs based on a sorted contingency table such that both its row and column marginal total are sorted in descending order instead of a lexicographical order used in previous studies. We then propose a new CSE algorithm which is the first proposed CSE algorithm using the new encoding order. Experimental results show that compression ratios of all files of the Calgary corpus in the proposed algorithms are better than those of a previous study on CSE with a finite alphabet. Moreover, compression ratios under the second proposed CSE get better than or equal to that under a well-known compressor for 11 files amongst 14 files in the corpus

六角形格子上の積符号を用いた符号化変調方式によるPAPRの低減

小形通信機器を用いる無線通信においては，寸法や重量が制限されるため，より電力効率の良い通信方式が求められる．本論文では，電力利用効率の良い通信方式として，六角形格子上の整数符号を用いた積符号による符号化変調方式を提案する．六角形格子は信号点の密度が高いため，等方性の19点六角形格子のピーク対平均電力比は矩形16値直交振幅変調(QAM: Quadrature Amplitude Modulation)よりも0.56dB低く抑えることができる．また，整数符号は，訂正可能な誤りを近接点に設定でき，遠方の信号点へ誤る確率よりも近接点へ誤る確率の方が高いと言う実際的な通信路に適している．本検討では，19，37及び61点の六角形格子上で整数符号単体及び整数符号と負巡回符号またはリード・ソロモン符号の積符号のシミュレーションを行った．その結果，整数符号とリード・ソロモン符号の積符号が，負巡回符号との積符号や各符号単体の結果と比べてビット誤り率(BER: Bit Error Rate)の改善効果が大きいことを示すことができた．また，信号点数の近い矩形QAMと比較してBERが1.0×10-5において0.8dBから1dBの符号化利得を得ることができ，提案符号化変調方式による電力及びBERの改善効果を確認できた．Wireless communication using small devices requires high power efficiency schemes because of size and weight constraints. In this paper, coded modulation schemes using product codes composed of integer codes over hexagonal constellations are proposed. The peak-to-average power ratio of an isotropy 19-Hexagonal constellation is 0.56 dB lower than that of 16QAM. In addition, integer codes can define its correctable error in the vicinity of signal points. Therefore, it is suitable for the practical communication channel. Our coded modulation simulation results over 19, 37 and 61 hexagonal constellations showed lower bit error rate than the results on square QAM constellations

Skeletal Metastasis in Renal Cell Carcinoma: Photon Deficiency on Bone Scintigraphy

Bone scintigraphy with 99mTc-labeled phosphorous compound is an excellent technique for the detection of bone metastasis. Bone metastases are usually visualized as multiple hot spots on bone scintigraphy. However, photon deficiency in the metastatic lesion on bone scintigrams is reported in few cases with malignancy. In this study, we have evaluated the photopenic bone metastasis from renal cell carcinoma by the radiographic and computed tomographic examinations. Photon deficient metastatic lesions were seen on bone scintigraphy in 5 patients with renal cell carcinoma. All of the photon deficient lesions were osteolytic on bone radiography and computed tomography. The pure photon deficient lesions not associated with surrounding hot margins were seen on the thoracic vertebrae and rib and the ones with surrounding hot margins were seen on the sternum, pelvis and femur. This difference may be due to the differences in the growth rate of the tumor and reactive hyperemia and new bone formation in the metastatic lesions