Neural Fourier Transform: A General Approach to Equivariant Representation Learning

Symmetry learning has proven to be an effective approach for extracting the hidden structure of data, with the concept of equivariance relation playing the central role. However, most of the current studies are built on architectural theory and corresponding assumptions on the form of data. We propose Neural Fourier Transform (NFT), a general framework of learning the latent linear action of the group without assuming explicit knowledge of how the group acts on data. We present the theoretical foundations of NFT and show that the existence of a linear equivariant feature, which has been assumed ubiquitously in equivariance learning, is equivalent to the existence of a group invariant kernel on the dataspace. We also provide experimental results to demonstrate the application of NFT in typical scenarios with varying levels of knowledge about the acting group

A comparison of the force applied on oral structures during intubation attempts between the Pentax-AWS airwayscope and the Macintosh laryngoscope: a high-fidelity simulator-based study

Objective: We sought to determine whether the use of Pentax-AWS Airwayscope (AWS) applied less force on oral structures during intubation attempts than a conventional direct laryngoscope (DL). Design: Prospective cross-over study. Participants: A total of 37 physicians (9 transitional-year residents, 20 emergency medicine residents and 8 emergency physicians) were enrolled. Interventions We used four simulation scenarios according to the difficulty of intubation and devices and used a high-fidelity simulator to quantify the forces applied on the oral structures. Outcome measures Primary outcomes were the maximum force applied on the maxillary incisors and tongue. Other outcomes of interest were time to intubation and glottic view during intubation attempts. Results: The maximum force applied on the maxillary incisors in the normal airway scenario was higher with the use of AWS than that with DL (107 newton (N) vs 77 N, p=0.02). By contrast, the force in the difficult airway scenario was significantly lower with the use of AWS than that of the DL (89 N vs 183 N, p<0.01). Likewise, the force applied on the tongue was significantly lower with the use of AWS than the use of DL in both airway scenarios (11 N vs 27 N, p<0.001 in the normal airway scenario; 12 N vs 40 N, p<0.01 in the difficult airway scenario). Conclusions: The use of AWS during intubation attempts was associated with decreased forces applied to oral structures in the simulated difficult airway scenario

Contents of Inscriptions on Stone Monuments Related to Flood or Debris Flow Disasters in Hiroshima Prefecture, Southwest Japan.

本研究では，広島県内の土石流や洪水に関する石碑の碑文の内容を整理・集約した。特に，漢文で刻まれた碑文の内容は理解することは難しいため，碑文を現代語に訳した。広島県では1909（明治42）年から現在までに水害碑が少なくとも38基建立されている。概して，第二次世界大戦前までの石碑は，災害の様子，復興の過程に関する詳細な情報が記述されるものが多い。一方，戦後の石碑は，災害の概要を端的に伝え，慰霊や復旧記念を目的とするものが多い。水害碑は，被災地の位置や被災当時の様子を，地域の住民に伝えることができる防災教育に資する媒体であり，本稿はその一助となると期待される。We examine contents of the inscriptions on all of the stone monuments related to flood or debris flow disasters in Hiroshima Prefecture, southwest Japan. Because it is difficult for people today to understand the meaning of the inscriptions, which were written in classical Chinese, we translate those in modern Japanese. At least 38 monuments were erected in Hiroshima Prefecture during the 106 years between 1909 and 2015. The contents of inscriptions from before World War II and during the war include plentiful information related to the process of erecting the monument, and details on disaster damage and restoration work. The contents inscribed on the monuments built after the war have mainly eulogized disaster victims or memorialized restoration work, and include only brief information on disaster damage. These monuments have the potential to inform local people about the situation and areas affected by past disasters. This research contributes to education for disaster prevention by increasing awareness of past disasters

Diffusion tensor imaging in elderly patients with idiopathic normal pressure hydrocephalus or Parkinson’s disease: diagnosis of gait abnormalities

BACKGROUND: Gait abnormalities in the elderly, characterized by short steps and frozen gait, can be caused by several diseases, including idiopathic normal pressure hydrocephalus (INPH), and Parkinson’s disease (PD). We analyzed the relationship between these two conditions and their association with gait abnormalities using laboratory test data and findings from diffusion tensor imaging (DTI). METHODS: The study involved 10 patients with INPH, 18 with PD, and 10 healthy individuals (control group). Fractional anisotropy (FA) of five brain areas was measured and compared among the three groups. In addition, the association of INPH and PD with gait capability, frontal lobe function, and FA of each brain area was evaluated. RESULTS: The INPH group had significantly lower FA for anterior thalamic radiation (ATR) and forceps minor (Fmin) as compared to the PD group. The gait capability correlated with ATR FA in the INPH and PD groups. We found that adding DTI to the diagnosis assisted the differential diagnosis of INPH from PD, beyond what could be inferred from ventricular size alone. CONCLUSIONS: We expect that DTI will provide a useful tool to support the differential diagnosis of INPH and PD and their respective severities

Consistent scaling of whole-shoot respiration between Moso bamboo (Phyllostachys pubescens) and trees

Both Moso bamboo (Phyllostachys pubescens) and tree forests have a large biomass; they are considered to play an important role in ecosystem carbon budgets. The scaling relationship between individual whole-shoot (i.e., aboveground parts) respiration and whole-shoot mass provides a clue for comparing the carbon budgets of Moso bamboo and tree forests. However, nobody has empirically demonstrated whether there is a difference between these forest types in the whole-shoot scaling relationship. We developed whole-shoot chambers and measured the shoot respiration of 58 individual mature bamboo shoots from the smallest to the largest in a Moso bamboo forest, and then compared them with that of 254 tree shoots previously measured. For 30 bamboo shoots, we measured the respiration rate of leaves, branches, and culms. We found that the scaling exponent of whole-shoot respiration of bamboo fitted by a simple power function on a log–log scale was 0.843 (95 % CI 0.797–0.885), which was consistent with that of trees, 0.826 (95 % CI 0.799–0.851), but higher than 3/4, the value typifying the Kleiber’s rule. The respiration rates of leaves, branches, and culms at the whole-shoot level were proportional to their mass, revealing a constant mean mass-specific respiration of 1.19, 0.224, and 0.0978 µmol CO2 kg- 1 s- 1, respectively. These constant values suggest common traits of organs among physiologically integrated ramets within a genet. Additionally, the larger the shoots, the smaller the allocation of organ mass to the metabolically active leaves, and the larger the allocation to the metabolically inactive culms. Therefore, these shifts in shoot-mass partitioning to leaves and culms caused a negative metabolic scaling of Moso bamboo shoots. The observed convergent metabolic scaling of Moso bamboo and trees may facilitate comparisons of the ecosystem carbon budgets of Moso bamboo and tree forests. © 2021, The Author(s)

Additional data on the stone monuments related to flood and debris flow disasters in Hiroshima Prefecture, southwest Japan, and the historical transition of those monuments.

本稿では，情報提供により新たに見いだした10 基の広島県内の水害碑の特徴について記載した上で，県内における近世の後半から現在までに建立された50 基の水害碑の歴史的変遷を明らかにする。県内の水害碑の全50基の属性（建立年，碑の縦横比，使用している文字，碑文の内容，文字数）を整理した結果，明治前～中期と，1950年代の二つの時期で碑の属性が大きく変わることが明らかになった。明治前～中期以降から1950年代までの碑は，縦長からなること，漢文や漢字片仮名交じり文からなること，被災や復旧に関する情報が豊富であること，災害からの復旧に尽力した個人を顕彰するものがあること，天皇からの下賜金を示すものがあることの特徴を持つ。1950年代以降の碑は，漢字平仮名交じり文からなること，被災や復旧に関する記述が少ないこと，慰霊を建立目的とする碑が多くなること，70年代以降には横長の碑が認められることの特徴をもつ。The inscriptions on 10 stone monuments related to flood or debris flow disasters in Hiroshima Prefecture, southwest Japan, were described. In total, there are 50 monuments in Hiroshima Prefecture based on our previous data and these additional data. Two turning points in the 1880s and 1950s were recognized based on the characteristics of the monuments in terms of their inscription contents, volume of contents, ratio of height and length of the monuments, and use of written language. Few monuments were built before the 1880s and their contents were less informative. Monuments erected from the 1880s to the 1950s were taller; their contents were characterized as detailed information relating to damage or restoration and were inscribed using kanbun, Chinese characters only, or kanji characters with katakana. The inscriptions on some monuments expressed residents’ appreciation for solatium from the Emperor or honored a person who contributed to the restoration after disaster. Fewer monuments built after the 1950s acknowledged disaster damage or restoration, and their contents were less informative, but more monuments were memorialized victims with a short message. The characters inscribed on these monuments were kanji with hiragana. Wider monuments were observed after the 1970s

SCC INVADING CEREBRAL BLOOD VESSELS

Squamous cell carcinoma (SCC) is known to have less brain metastasis, but the reasons are not well established. Herein, we report the case of an 82-year-old man with recurrent cerebral hemorrhage of unknown cause ; upon brain biopsy, SCC was diagnosed infiltrating peripheral blood vessels of the brain and that it was state of micro-metastasis. It is possible that the blood-brain barrier blocked the infiltration of SCC into the brain parenchyma, and it did not form a mass in the brain parenchyma. In addition, because it did not form a mass, it could not be diagnosed as a metastatic brain tumor by contrast-enhanced magnetic resonance imaging or contrast-enhanced computed tomography. Among cases of recurrent cerebral hemorrhage of unknown cause in a short period, there may be cases of vascular infiltration without crossing the blood-brain barrier. Thus, if similar cases of recurrent cerebral hemorrhage of unknown cause is observed, it is necessary to distinguish metastatic brain tumors even if there is no evidence of suspected tumor on contrast-enhanced magnetic resonance imaging scan

下部直腸癌におけるMRIを用いた歯状線浸潤の診断精度

Purpose: To retrospectively assess the accuracy of magnetic resonance imaging (MRI) in predicting dentate line invasion in low rectal cancer. Materials and methods: Eighty-one patients with primary rectal cancer were assessed by dynamic contrast-enhanced MRI. The location of the dentate line was assessed on MRI in 27 patients with upper-mid rectal cancer. Two observers independently evaluated the distance between the distal tumor edge and the MRI-defined dentate line in 54 patients with low rectal cancer, and the imaging and histological findings were compared. Results: The MRI-defined dentate line was 24.0 ± 3.8 mm above the anal verge in patients with upper-mid rectal cancer. The dentate line invasion status agreed with the histological findings in 49/54 (91%) patients (κ = 0.72 [95% CI 0.50-0.95]) for observer 1, and in 51/54 (94%) patients (κ = 0.83 [0.65-1.00]) for observer 2 in patients with low rectal cancer. Interobserver agreement was good (κ = 0.83 [0.65-1.00]). The MRI-derived distance between the distal tumor edge and the dentate line had significant correlation with the histological distance (r = 0.86 for reader 1 and 0.75 for observer 2). Conclusion: MRI demonstrates high accuracy in predicting dentate line invasion in low rectal cancer.博士（医学）・甲第748号・令和2年6月30日© Japan Radiological Society 2020© 2020 Springer Nature Switzerland AG. Part of Springer Nature.This is a post-peer-review, pre-copyedit version of an article published in Japanese journal of radiology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s11604-020-00933-5