Neuromorphic application of oxide semiconductors

Artificial intelligences are promising as key technologies in future societies. However, the conventional ones are executed using complicated software on high-specked hardware, and the machine size is very bulky and power consumption is unbelievably huge. Therefore, we are investigating braintype integrated system , namely, neural network built only by hardware, which can be compact, low power, robust, and integrated on everything in future. In order to realize that system, simplification of the processing elements, such as neurons and synapse, three-dimensional structure, and low cost fabrication are required. We have succeeded in that simplification and are trying to utilize oxide semiconductors for the neuromorphic application because they can be fabricated using low cost fabrication such as sputtering and printing, by which the three-dimensional structure can be obtained in future. Please click Additional Files below to see the full abstract

Tissue engineering of corneal stroma with rabbit fibroblast precursors and gelatin hydrogels

PURPOSE: To isolate fibroblast precursors from rabbit corneal stroma using a sphere-forming assay, to engineer corneal stroma with the precursors and gelatin, and to establish the therapeutic application of precursors in a rabbit corneal stroma. METHODS: In the in vitro study, a sphere-forming assay was performed to produce precursors from rabbit corneal stroma. Corneal stroma was engineered by cultivating precursors in porous gelatin for one week. In the in vivo study, the engineered corneal stromal sheet with precursors (precursor/gelatin group) or with fibroblasts (fibroblast /gelatin group) or without cells (gelatin group) was transplanted to a pocket of rabbit corneal stroma. Gene expression and extracellular matrix production were examined immunohistochemically in each group one week and four weeks after surgery. RESULTS: In the in vitro study, cells in the spheres were BrdU-positive, and their progeny were keratocan-positive. The study also showed that the corneas transplanted with a porous gelatin sheet did not show any opacity four weeks after transplantation in any group. In the gelatin sheet of the precursor/gelatin group, a more intense expression of type I collagen was observed relative to the other two groups four weeks after the surgery. CONCLUSIONS: Our findings demonstrate that the transplantation of fibroblast precursors combined with gelatin hydrogel into the corneal stroma is a possible treatment strategy for corneal stromal regeneration

Inhomogeneous superconductivity in thin crystals of FeSe1-xTex (x=1.0, 0.95, and 0.9)

We investigated the temperature dependence of resistivity in thin crystals of FeSe1-xTex (x = 1.0, 0.95, and 0.9), though bulk crystals with 1.0 x 0.9 are known to be non-superconducting. With decreasing thickness of the crystals, the resistivity of x = 0.95 and 0.9 decreases and reaches zero at a low temperature, which indicates a clear superconducting transition. The anomaly of resistivity related to the structural and magnetic transitions completely disappears in 55- to 155-nm-thick crystals of x = 0.9, resulting in metallic behavior in the normal state. Microbeam x-ray diffraction measurements were performed on bulk single crystals and thin crystals of FeSe1-xTex. A significant difference of the lattice constant, c, was observed in FeSe1-xTex, which varied with differing Te content (x), and even in crystals with the same x, which was mainly caused by inhomogeneity of the Se/Te distribution. It has been found that the characteristic temperatures causing the structural and magnetic transition (T-t), the superconducting transition (T-c), and the zero resistivity (T-c(zero)) are closely related to the value of c in thin crystals of FeSe1-xTex

fRNAdb: a platform for mining/annotating functional RNA candidates from non-coding RNA sequences

There are abundance of transcripts that code for no particular protein and that remain functionally uncharacterized. Some of these transcripts may have novel functions while others might be junk transcripts. Unfortunately, the experimental validation of such transcripts to find functional non-coding RNA candidates is very costly. Therefore, our primary interest is to computationally mine candidate functional transcripts from a pool of uncharacterized transcripts. We introduce fRNAdb: a novel database service that hosts a large collection of non-coding transcripts including annotated/non-annotated sequences from the H-inv database, NONCODE and RNAdb. A set of computational analyses have been performed on the included sequences. These analyses include RNA secondary structure motif discovery, EST support evaluation, cis-regulatory element search, protein homology search, etc. fRNAdb provides an efficient interface to help users filter out particular transcripts under their own criteria to sort out functional RNA candidates. fRNAdb is available a

Dysregulated Aire expression and autoimmunity

Deficiency for AIRE/Aire in both humans and mice results in the development of organ-specific autoimmune disease. We tested whether augmented and/or dysregulated AIRE/Aire expression might be also prone to the breakdown of self-tolerance. To define the effect of augmented Aire expression on the development of autoimmunity, antigen-specific clonal deletion and production of clonotypic regulatory T cells (Tregs) in the thymus were examined using mice expressing two additional copies of Aire in a heterozygous state (3xAire-knockin mice: 3xAire-KI). We found that both clonal deletion of autoreactive T cells and production of clonotypic Tregs in the thymus from 3xAire-KI were impaired in a T-cell receptor-transgenic system. Furthermore, 3xAire-KI females showed higher scores of experimental autoimmune encephalomyelitis induced by myelin oligodendrocyte glycoprotein than wild-type littermates, suggesting that augmented Aire expression exacerbates organ-specific autoimmunity under disease-prone conditions. In humans, we found that one patient with amyopathic dermatomyositis showed CD3–CD19– cells expressing AIRE in the peripheral blood before the treatment but not during the remission phase treated with immunosuppressive drugs. Thus, not only loss of function of AIRE/Aire but also augmented and/or dysregulated expression of AIRE/Aire should be considered for the pathogenesis of organ-specific autoimmunity. We suggest that further analyses should be pursued to establish a novel link between organ-specific autoimmune disease and dysregulated AIRE expression in clinical settings

Effect of Focal X-ray Irradiation on Experimental Choroidal Neovascularization

PURPOSE. Radiation therapy has been used to treat choroidal neovascularization (CNV) in patients with age-related macular degeneration. The in vivo effect of applying focal x-ray irradiation to the eye of rabbits with experimental CNV was investigated. METHODS. CNV was induced in the rabbit eyes by subretinal implantation of gelatin hydrogel microspheres impregnated with basic fibroblast growth factor. Three weeks after implantation, 17 of 34 eyes with CNV lesions accompanied by fluorescein leakage were irradiated with a single dose of 20 Gy; the other 17 eyes were not irradiated and served as the controls. The eyes were examined before irradiation and 1, 2, and 4 weeks after irradiation, by indirect ophthalmoscopy and fluorescein angiography. The degree of a decreasing amount of fluorescein leakage from the CNV lesions after irradiation was graded using a computerized image analysis system and was compared in the irradiated and nonirradiated eyes. These eyes were also examined histologically and immunohistochemically. RESULTS. Fluorescein leakage from the CNV lesions had significantly decreased in the eyes irradiated with 20 Gy compared with the control eyes, throughout the study period (P < 0.05). Histologic and immunohistochemical studies at 4 weeks after irradiation demonstrated that the degree of vascular formation and the number of vascular endothelial cells in the subretinal membrane of the irradiated eyes were less than those of the control eyes. CONCLUSIONS. Focal x-ray irradiation at the ocular region effectively reduced experimental CNV activity. These results support the possibility that radiation therapy may be beneficial in treating CNV. (Invest Ophthalmol Vis Set. 1999;40:l496-1502

国語辞典編集のための用例データベース

国立国語研究所国立国語研究所国立国語研究所The National Language Research InstituteThe National Language Research InstituteThe National Language Research Institute既存の辞書に依存しないオリジナルな辞書を作るためには,まず生の用例をたくさん集める必要がある。国立国語研究所国語辞典編集室では,昭和54年に準備室が発足して以来,用例採集のための目録作り,作業手順の検討などを行うとともに,国定読本を資料として試験的に用例採集作業を開始した。昭和63年に正式の室になってからは,雑誌を対象に本格的な用例採集を開始し,続いて文学作品・国定算数教科書などに手をつけた。当面対象とする年代は,1901～1950年であるが,いずれは範囲を広げる予定である。国定読本についてはすでにコンコーダンスが完成し,『国定読本用語総覧』1～12及びCD－ROMを刊行した(三省堂)。国定算数教科書についてもKWICと語彙表ができており,インターネット上での公開を考えている。現在最も力を注いでいるのが総合雑誌『太陽』であるが,これも3,4年のうちに,電子媒体で出版することになるだろう。文学作品については,多数の作家にわたるよう,短い作品をえらんで作業を進めている。We are building a "yoorei database" (assembled concordances) for the purpose of compiling an original dictionary that is not dependent upon existing dictionaries. We assume that standard Japanese was established between 1901 and 1950. We set this period as our starting point to build our "yoorei database". In order to cover a wide range of our database objects, we take into consideration such materials as school textbooks, newspapers, magazines, literary works, best selling books, and the Diet Record. Three sets of materials that have already been worked on follow. 1. Japanese school textbooks written by the Ministry of Education (Completed) "Kokutei Tokuhon Yoogo Sooran" (A concordance of Kokutei Tokuhon) vol. 1-12 and CD-ROM version. Total number of words: 600,000 Total number of different words: 32,000 These numbers were counted by the "zensuu-shiki" method (to make a concordance of whole words from a data set). 2. Popular magazine "Taiyoo" 62 volumes (In progress. Planned to be done within 3-4 years.) Total number of words: 550,000 by the "scout-shiki" method (to make a concordance of selected words by "scout standard" from a data set). We are inputting the text data of the entire 62 volumes in order to provide contexts for the materials. We estimate that this text data set will consist of 8,000,000 characters. 3. Literary works: 334 stories (In progress) We chose 334 various short stories (including novels, essays, critical essays, drama and juvenile stories) from the point of view of creating a well-balanced concordance. We estimate the total number of words at 1,700,000, excluding postpositional particles and auxiliary verbs. 4. Arithmetic school textbooks written by the Ministry of Education (Completed) KWIC (Key Word In Context) data and the lexicon from this material have already been done. (Unpublished) Total number of words: 200,000 Total number of different words: 6,600 We have tentatively tried different methods for each data set. At this point, however, we are planning to make a manual (for building the "yoorei database") more complete in order to build the database using the most effective methods

Bile Duct Regeneration with an Artificial Bile Duct Made of Gelatin Hydrogel Nonwoven Fabrics

Although choledochojejunostomy is the standard technique for biliary reconstruction, there are various associated problems that need to be solved such as reflux cholangitis. Interposition with an artificial bile duct (ABD) to replace the resected bile duct maintains a physiological conduit for bile and may solve this problem. This study investigated the usefulness of an ABD made of gelatin hydrogel nonwoven fabric (GHNF). GHNF was prepared by the solution blow spinning method. The migration and activity of murine fibroblast L929 cells were examined in GHNF sheets. L929 cells migrated into GHNF sheets, where they proliferated and synthesized collagen, suggesting GHNF is a promising scaffold for bile duct regeneration. ABDs made of GHNF were implanted in place of resected bile duct segments in rats. The rats were killed at 2, 6, and 12 weeks postimplantation. The implantation site was histologically evaluated for bile duct regeneration. At postoperative 2 weeks, migrating cells were observed in the ABD pores. The implanted ABD was mostly degraded and replaced by collagen fibers at 6 weeks. Ki67-positive bile duct epithelial cells appeared within the implanted ABD. These were most abundant within the central part of the ABD after 6 weeks. The percentages of Ki67-positive cells were 31.7 ± 9.1% in the experimental group and 0.8 ± 0.6% in the sham operation group at 6 weeks (p < 0.05), indicating that mature biliary epithelial cells at the stump proliferated to regenerate the biliary epithelium. Biliary epithelial cells had almost completely covered the bile duct lumen at 12 weeks (epithelialization ratios: 10.4 ± 6.9% at 2 weeks, 93.1 ± 5.1% at 6 weeks, 99.2 ± 1.6% at 12 weeks). The regenerated epithelium was positive for the bile duct epithelium marker cytokeratin 19. Bile duct regeneration was accompanied by angiogenesis, as evidenced by the appearance of CD31-positive vascular structures. Capillaries were induced 2 weeks after implantation. The number of capillaries reached a maximum at 6 weeks and decreased to the same level as that of normal bile ducts at 12 weeks. These results showed that an ABD of GHNF contributed to successful bile duct regeneration in rats by facilitating the cell migration required for extracellular matrix synthesis, angiogenesis, and epithelialization. Impact Statement Development of an artificial bile duct (ABD) enables physiological biliary reconstruction and may solve clinical problems associated with choledochojejunostomy. In this study, we created ABDs with gelatin hydrogel nonwoven fabric and implanted them in place of resected bile duct in rats. We evaluated the process of bile duct regeneration as well as decomposition of the ABD and demonstrated successful regeneration of resected bile duct, highlighting the possibility of this novel biliary reconstruction method to replace choledochojejunostomy

From segment to somite: segmentation to epithelialization analyzed within quantitative frameworks

One of the most visually striking patterns in the early developing embryo is somite segmentation. Somites form as repeated, periodic structures in pairs along nearly the entire caudal vertebrate axis. The morphological process involves short- and long-range signals that drive cell rearrangements and cell shaping to create discrete, epithelialized segments. Key to developing novel strategies to prevent somite birth defects that involve axial bone and skeletal muscle development is understanding how the molecular choreography is coordinated across multiple spatial scales and in a repeating temporal manner. Mathematical models have emerged as useful tools to integrate spatiotemporal data and simulate model mechanisms to provide unique insights into somite pattern formation. In this short review, we present two quantitative frameworks that address the morphogenesis from segment to somite and discuss recent data of segmentation and epithelialization