Bunkyo University
UniversityTokyo, Japan
Research output, citation impact, and the most-cited recent papers from Bunkyo University (Japan). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Bunkyo University
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) scanner on NASA's Earth Observing System (EOS)-AM1 satellite (launch scheduled for 1998) will collect five bands of thermal infrared (TIR) data with a noise equivalent temperature difference (NE/spl Delta/T) of /spl les/0.3 K to estimate surface temperatures and emissivity spectra, especially over land, where emissivities are not known in advance. Temperature/emissivity separation (TES) is difficult because there are five measurements but six unknowns. Various approaches have been used to constrain the extra degree of freedom. ASTER's TES algorithm hybridizes three established algorithms, first estimating the normalized emissivities and then calculating emissivity band ratios. An empirical relationship predicts the minimum emissivity from the spectral contrast of the ratioed values, permitting recovery of the emissivity spectrum. TES uses an iterative approach to remove reflected sky irradiance. Based on numerical simulation, TES should be able to recover temperatures within about /spl plusmn/1.5 K and emissivities within about /spl plusmn/0.015. Validation using airborne simulator images taken over playas and ponds in central Nevada demonstrates that, with proper atmospheric compensation, it is possible to meet the theoretical expectations. The main sources of uncertainty in the output temperature and emissivity images are the empirical relationship between emissivity values and spectral contrast, compensation for reflected sky irradiance, and ASTER's precision, calibration, and atmospheric compensation.
Tumor recurrence is a leading cause of cancer mortality. Therapies for recurrent disease may fail, at least in part, because the genomic alterations driving the growth of recurrences are distinct from those in the initial tumor. To explore this hypothesis, we sequenced the exomes of 23 initial low-grade gliomas and recurrent tumors resected from the same patients. In 43% of cases, at least half of the mutations in the initial tumor were undetected at recurrence, including driver mutations in TP53, ATRX, SMARCA4, and BRAF; this suggests that recurrent tumors are often seeded by cells derived from the initial tumor at a very early stage of their evolution. Notably, tumors from 6 of 10 patients treated with the chemotherapeutic drug temozolomide (TMZ) followed an alternative evolutionary path to high-grade glioma. At recurrence, these tumors were hypermutated and harbored driver mutations in the RB (retinoblastoma) and Akt-mTOR (mammalian target of rapamycin) pathways that bore the signature of TMZ-induced mutagenesis.
The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.
Stretchability will significantly expand the application scope of electronics, particularly large-area electronics-displays, sensors, and actuators. If arbitrary surfaces and movable parts could be covered with stretchable electronics, which is impossible with conventional electronics, new classes of applications are expected to emerge. A large hurdle is manufacturing electrical wiring with high conductivity, high stretchability, and large-area compatibility. This Review describes stretchable, large-area electronics based on organic field-effect transistors for applications to sensors and displays. First, novel net-shaped organic transistors are employed to realize stretchable, large-area sensor networks that detect distributions of pressure and temperature simultaneously. The whole system is functional even when it is stretched by 25%. In order to further improve stretchability, printable elastic conductors are developed by dispersing single-walled carbon nanotubes (SWNTs) as dopants uniformly in rubbers. Further, we describe integration of printable elastic conductors with organic transistors to construct a rubber-like stretchable active matrix for large-area sensor and display applications. Finally, we will discuss the future prospects of stretchable, large-area electronics with delineating a picture of the next-generation human/machine interfaces from the aspect of materials science and electronic engineering.
A criterion to determine the existence of zero-energy edge states is discussed for a class of particle-hole symmetric Hamiltonians. A "loop" in a parameter space is assigned for each one-dimensional bulk Hamiltonian, and its topological properties, combined with the chiral symmetry, play an essential role. It provides a unified framework to discuss zero-energy edge modes for several systems such as fully gapped superconductors, two-dimensional d-wave superconductors, and graphite ribbons. A variance of the Peierls instability caused by the presence of edges is also discussed.
Calpain, calcium-activated neutral protease, stands as a unique receptor for calcium signals in biological systems; its activation leads to irreversible proteolytic processing of substrate proteins, modifying cellular situations in a manner distinct from that of reversible processes including the phosphorylation-dephosphorylation reactions. Because the enzyme participates not only in normal intracellular signal transduction cascades but also in various pathological states including ischemia, calpain research has attracted tremendous interest in wide areas of life sciences in both basic and clinical terms. This review will address the new perspectives evoked by recent discoveries since 1990. Molecular biological studies have established that calpain in fact constitutes a large family of distinct isozymes differing in structure and distribution, whereas an increasing number of reports describe physiological-pathological involvement of calpain. Another major accomplishment is the technical breakthrough allowing spatial resolution of calpain action presenting a clearer in vivo picture of how calpain acts in cells and tissues.
In order to evaluate a possible therapy for hypersplenism, an experiment with animals was done. In nine dogs, 0.6 ml/kg body weight of 5% ethanolamine oleate was injected percutaneously into the spleen under ultrasound guidance. The injection was repeated three times at intervals of 1 week. Three dogs each were killed at 1, 4, and 8 weeks after the final injection. All dogs tolerated the procedure well and lived until they were killed. The platelet count and leukocyte count increased after the injections, and remained higher than the pretreatment level until death. This effect probably is due to depressed splenic function. The autopsy showed 40% of the spleen to be infarcted with complete destruction of the normal structure. No serious complications occurred. In addition, injection of ethanolamine oleate in six fully heparinized dogs showed that there was little risk of hemorrhage. Ultrasound-guided percutaneous injection of ethanolamine oleate might be a simple and effective therapy for hypersplenism.
This paper explores a global trend where universities are collaborating with government, industry and civil society to advance the sustainable transformation of a specific geographical area or societal sub-system. With empirical evidence, we argue that this function of ‘co-creation for sustainability’ could be interpreted as the seeds of an emerging, new mission for the university. We demonstrate that this still evolving mission differs significantly from the economic focus of the third mission and conventional technology transfer practices, which we argue, should be critically examined. After defining five channels through which a university can fulfil the emerging mission, we analyse two frontrunner ‘transformative institutions’ engaged in co-creating social, technical and environmental transformations in pursuit of materialising sustainable development in a specific city. This study seeks to add to the debate on the third mission and triple-helix partnerships. It does so by incorporating sustainable development and place-based co-creation with government, industry and civil society.
Abstract The interaction of clinically established anti-inflammatory drugs with some proteins has shown these drugs to strongly inhibit heat coagulation of whole serum at a concentration attainable in the sera of patients. Phenylbutazone and sodium salicylate do not inhibit the biological activity of three biologically active and labile serum proteins, namely, necrotizing factor, heterogenous serum and complement. However, they do influence the effect of heat on these proteins. The relation between this drug action in vitro and the possible mode of action of the proteins in vivo is discussed.
In an attempt to identify transcription factors which activate sterol-regulatory element-binding protein 1c (SREBP-1c) transcription, we screened an expression cDNA library from adipose tissue of SREBP-1 knockout mice using a reporter gene containing the 2.6-kb mouse SREBP-1 gene promoter. We cloned and identified the oxysterol receptors liver X receptor (LXRalpha) and LXRbeta as strong activators of the mouse SREBP-1c promoter. In the transfection studies, expression of either LXRalpha or -beta activated the SREBP-1c promoter-luciferase gene in a dose-dependent manner. Deletion and mutation studies, as well as gel mobility shift assays, located an LXR response element complex consisting of two new LXR-binding motifs which showed high similarity to an LXR response element recently found in the ABC1 gene promoter, a reverse cholesterol transporter. Addition of an LXR ligand, 22(R)-hydroxycholesterol, increased the promoter activity. Coexpression of retinoid X receptor (RXR), a heterodimeric partner, and its ligand 9-cis-retinoic acid also synergistically activated the SREBP-1c promoter. In HepG2 cells, SREBP-1c mRNA and precursor protein levels were induced by treatment with 22(R)-hydroxycholesterol and 9-cis-retinoic acid, confirming that endogenous LXR-RXR activation can induce endogenous SREBP-1c expression. The activation of SREBP-1c by LXR is associated with a slight increase in nuclear SREBP-1c, resulting in activation of the gene for fatty acid synthase, one of its downstream genes, as measured by the luciferase assay. These data demonstrate that LXR-RXR can modify the expression of genes for lipogenic enzymes by regulating SREBP-1c expression, providing a novel link between fatty acid and cholesterol metabolism.
Over the past few decades, supramolecular chirality in discrete metallosupramolecular architectures has received considerable attention. In this review, a comprehensive summary of discrete, chiral coordination-driven structures, including helices, metallacycles, metallocages, etc., is presented. Although chirality can be introduced prior to, during or even after the coordination self-assembly process, this review puts major emphasis on the more recent development of metallosupramolecular architectures from chiral components, where chirality arises from the enantiopure or racemic scaffolds (bridging or auxiliary ligand). Special attention will be paid to homochiral metallo-assemblies using achiral components where chirality is obtained as a consequence of the twisting of the ligands. Additionally, the potential applications of homochiral metallosupramolecular architectures are also discussed. We hope that this review will be of interest to researchers attempting to design new elaborate homochiral metallosupramolecular architectures with even greater complexity and potential for functions such as chiral recognition, enantiomer separation, asymmetric catalysis, nonlinear sensors, and devices.
Twitter has received much attention recently. An important characteristic of Twitter is its real-time nature. We investigate the real-time interaction of events such as earthquakes in Twitter and propose an algorithm to monitor tweets and to detect a target event. To detect a target event, we devise a classifier of tweets based on features such as the keywords in a tweet, the number of words, and their context. Subsequently, we produce a probabilistic spatiotemporal model for the target event that can find the center of the event location. We regard each Twitter user as a sensor and apply particle filtering, which are widely used for location estimation. The particle filter works better than other comparable methods for estimating the locations of target events. As an application, we develop an earthquake reporting system for use in Japan. Because of the numerous earthquakes and the large number of Twitter users throughout the country, we can detect an earthquake with high probability (93 percent of earthquakes of Japan Meteorological Agency (JMA) seismic intensity scale 3 or more are detected) merely by monitoring tweets. Our system detects earthquakes promptly and notification is delivered much faster than JMA broadcast announcements.
Abstract Pressure‐stabilized hydrides are a new rapidly growing class of high‐temperature superconductors, which is believed to be described within the conventional phonon‐mediated mechanism of coupling. Here, the synthesis of one of the best‐known high‐ T C superconductors—yttrium hexahydride ‐YH 6 is reported, which displays a superconducting transition at ≈224 K at 166 GPa. The extrapolated upper critical magnetic field B c2 (0) of YH 6 is surprisingly high: 116–158 T, which is 2–2.5 times larger than the calculated value. A pronounced shift of T C in yttrium deuteride YD 6 with the isotope coefficient 0.4 supports the phonon‐assisted superconductivity. Current–voltage measurements show that the critical current I C and its density J C may exceed 1.75 A and 3500 A mm −2 at 4 K, respectively, which is higher than that of the commercial superconductors, such as NbTi and YBCO. The results of superconducting density functional theory (SCDFT) and anharmonic calculations, together with anomalously high critical magnetic field, suggest notable departures of the superconducting properties from the conventional Migdal–Eliashberg and Bardeen–Cooper–Schrieffer theories, and presence of an additional mechanism of superconductivity.
Abstract Efficient energy storage is a driving factor propelling myriads of mobile electronics, electric vehicles and stationary electric grid storage. Li‐ion batteries have realized these goals in a commercially viable manner with ever increasing penetration to different technology sectors across the globe. While these electronic devices are more evident and appealing to consumers, there has been a growing concern for micro‐to‐mega grid storage systems. Overall, the modern world demands energy in ‘terawatt’ scale. It needs a multipronged approach with alternate technologies complementing the Li‐ion batteries. One such viable approach is to design and implement Na‐ion batteries. With the uniform geographical distribution, abundance and materials economy of Na resources as well as a striking operational similarity to Li‐ion batteries, Na‐ion batteries have commercial potential, particularly for applications unrestricted by volumetric/gravimetric energy density. In pursuit of the development of Na‐ion batteries, suites of oxides, sulfides, fluorides, and polyanionic materials have been reported in addition to several organic complexes. This article gives an overview of recent progress in polyanionic framework compounds, with emphasis on high‐voltage candidates consisting of earth abundant elements. Guided by ternary phase diagrams, recently discovered and potential cathode candidates will be discussed gauging their performance, current status, and future perspectives.
In spite of the clinical usefulness of cisplatin (CDDP), there are many occasions in which it is difficult to continue the administration of CDDP due to its nephrotoxicity and neurotoxicity. We examined the incorporation of CDDP into polymeric micelles to see if this allowed the resolution of these disadvantages. Cisplatin was incorporated into polymeric micelles through the polymer-metal complex formation between polyethylene glycol poly(glutamic acid) block copolymers and CDDP (NC-6004). The pharmacokinetics, pharmacodynamics, and toxicity studies of CDDP and NC-6004 were conducted in rats or mice. The particle size of NC-6004 was approximately 30 nm, with a narrow size distribution. In rats, the area under the curve and total body clearance values for NC-6004 were 65-fold and one-nineteenth the values for CDDP (P<0.001 and 0.01, respectively). In MKN-45-implanted mice, NC-6004 tended to show antitumour activity, which was comparable to or greater than that of CDDP. Histopathological and biochemical studies revealed that NC-6004 significantly inhibited the nephrotoxicity of CDDP. On the other hand, blood biochemistry revealed transient hepatotoxicity on day 7 after the administration of NC-6004. Furthermore, rats given CDDP showed a significant delay (P<0.05) in sensory nerve conduction velocity in their hind paws as compared with rats given NC-6004. Electron microscopy in rats given CDDP indicated the degeneration of the sciatic nerve, but these findings were not seen in rats given NC-6004. These results were presumably attributable to the significantly reduced accumulation of platinum in nerve tissue when NC-6004 was administered (P<0.05). NC-6004 preserved the antitumour activity of CDDP and reduced its nephrotoxicity and neurotoxicity, which would therefore seem to suggest that NC-6004 could allow the long-term administration of CDDP where caution against hepatic dysfunction must be exercised.
The present study was designed to identify recent clinical phenotypes using the National Epidemiological Survey and to compare findings with those of previous surveys in Japan. Pathologically confirmed sarcoidosis cases newly diagnosed in 2004 were eligible for the present study. Disease parameters were recorded and compared. A total of 1,027 patients were enrolled from a cluster encompassing 79.4% of the entire Japanese population. The study participants consisted of 364 males and 663 females, providing an average incidence rate of 1.01 per 100,000 inhabitants (0.73 for males and 1.28 for females). The age-specific incidence rate displayed a biphasic pattern in the whole patient population and in the females. The male incidence rates peaked in the 20-34-yr-old group. A second peak for 50-60-yr-old females showed a higher incidence than the first younger peak. Patients with abnormalities in eyes, skin and cardiac laboratory findings accounted for 54.8, 35.4 and 23.0% of cases, respectively. The female/male incidence ratio was increased, and the frequency of eye and skin involvement and cardiac abnormality was higher than in previous surveys conducted in Japan. In conclusion, the data obtained in the present study differ from those of other countries and showed changes in sarcoidosis clinical phenotypes compared with previous studies in Japan.
The results of the third phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first and second phase results. With improved detector calibrations, a full detector simulation, and improved analysis methods, the systematic uncertainty on the total neutrino flux is estimated to be $\ifmmode\pm\else\textpm\fi{}2.1%$, which is about two thirds of the systematic uncertainty for the first phase of Super-Kamiokande. The observed $^{8}\mathrm{B}$ solar flux in the 5.0 to 20 MeV total electron energy region is $2.32\ifmmode\pm\else\textpm\fi{}0.04(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.05(\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{sec}}^{\ensuremath{-}1}$ under the assumption of pure electron-flavor content, in agreement with previous measurements. A combined oscillation analysis is carried out using SK-I, II, and III data, and the results are also combined with the results of other solar neutrino experiments. The best-fit oscillation parameters are obtained to be ${sin}^{2}{\ensuremath{\theta}}_{12}={0.30}_{\ensuremath{-}0.01}^{+0.02}({tan}^{2}{\ensuremath{\theta}}_{12}={0.42}_{\ensuremath{-}0.02}^{+0.04})$ and $\ensuremath{\Delta}{m}_{21}^{2}={6.2}_{\ensuremath{-}1.9}^{+1.1}\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. Combined with KamLAND results, the best-fit oscillation parameters are found to be ${sin}^{2}{\ensuremath{\theta}}_{12}=0.31\ifmmode\pm\else\textpm\fi{}0.01({tan}^{2}{\ensuremath{\theta}}_{12}=0.44\ifmmode\pm\else\textpm\fi{}0.03)$ and $\ensuremath{\Delta}{m}_{21}^{2}=7.6\ifmmode\pm\else\textpm\fi{}0.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }{\mathrm{eV}}^{2}$. The $^{8}\mathrm{B}$ neutrino flux obtained from global solar neutrino experiments is $5.3\ifmmode\pm\else\textpm\fi{}0.2(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$, while the $^{8}\mathrm{B}$ flux becomes $5.1\ifmmode\pm\else\textpm\fi{}0.1(\mathrm{stat}+\mathrm{sys})\ifmmode\times\else\texttimes\fi{}{10}^{6}\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ by adding KamLAND results. In a three-flavor analysis combining all solar neutrino experiments, the upper limit of ${sin}^{2}{\ensuremath{\theta}}_{13}$ is 0.060 at 95% C.L.. After combination with KamLAND results, the upper limit of ${sin}^{2}{\ensuremath{\theta}}_{13}$ is found to be 0.059 at 95% C.L.
BACKGROUND AND AIMS: Helicobacter pylori infection and gastric atrophy are both risk factors for gastric cancer. We aimed to elucidate the natural history of gastric cancer development according to H pylori infection and gastric atrophy status. SUBJECTS AND METHODS: A total of 9293 participants in a mass health appraisal programme were candidates for inclusion in the present prospective cohort study: 6983 subjects revisited the follow up programme. Subjects were classified into four groups according to serological status at initial endoscopy. Group A (n = 3324) had "normal" pepsinogen and were negative for H pylori antibody; group B (n = 2134) had "normal" pepsinogen and were positive for H pylori antibody; group C (n = 1082) had "atrophic" pepsinogen and were positive for H pylori antibody; and group D (n = 443) had "atrophic" pepsinogen and were negative for H pylori antibody. Incidence of gastric cancer was determined by annual endoscopic examination. RESULTS: Mean duration of follow up was 4.7 years and the average number of endoscopic examinations was 5.1. The annual incidence of gastric cancer was 0.04% (95% confidence interval (CI) 0.02-0.09), 0.06% (0.03-0.13), 0.35% (0.23-0.57), and 0.60% (0.34-1.05) in groups A, B, C, and D, respectively. Hazard ratios compared with group A were 1.1 (95% CI 0.4-3.4), 6.0 (2.4-14.5), and 8.2 (3.2-21.5) in groups B, C, and D, respectively. Age, sex, and "group" significantly served as independent valuables by multivariate analysis. CONCLUSIONS: The combination of serum pepsinogen and anti-H pylori antibody provides a good predictive marker for the development of gastric cancer.
A 4-kilobase complementary DNA (cDNA) encoding human macrophage-specific colony-stimulating factor (CSF-1) was isolated. When introduced into mammalian cells, this cDNA directs the expression of CSF-1 that is structurally and functionally indistinguishable from the natural human urinary CSF-1. Direct structural analysis of both the recombinant CSF-1 and the purified human urinary protein revealed that these species contain a sequence of at least 40 amino acids at their carboxyl termini which are not found in the coding region of a 1.6-kilobase CSF-1 cDNA that was previously described. These results demonstrate that the human CSF-1 gene can be expressed to yield at least two different messenger RNA species that encode distinct but related forms of CSF-1.
Abstract Hard carbon is a standard anode material for Na‐ion batteries. However, its low crystallinity and diverse microstructures make obtaining a full understanding of the sodium storage mechanism challenging. Here, the results of a systematic ex situ small and wide angle X‐ray scattering study of a series of nanostructured hard carbons, which reveal clear evidence of sodium storage in the graphene–graphene interlayers and nanopores, are presented. Particularly, an emergence of a broad peak around q ≈ 2.0–2.1 Å −1 in the low voltage region is suggested to be an indicator that sodium is densely confined in the nanopores. Thus, classical X‐ray scattering techniques are demonstrated to be effective in elucidating the overall reaction scheme of Na insertion into hard carbon.