194 research outputs found

    Ultimate low system dark count rate for superconducting nanowire single-photon detector

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    The dark count rate (DCR) is a key parameter of single-photon detectors. By introducing a bulk optical band-pass filter mounted on a fiber-to-fiber optical bench cooled at 3 K and blocking down to 5 micrometer, we suppressed the DCR of a superconducting nanowire single-photon detector by more than three orders of magnitude. The DCR is limited by the blackbody radiation through a signal passband of 20 nm bandwidth. The figure of merit, system detection efficiency, and DCR were 2.7 x 10^11, 2.3 %, and 0.001 Hz, respectively. Narrowing the bandwidth to 100 GHz suppresses the DCR to 0.0001 Hz and the figure of merit increases to 1.8 x 10^12.Comment: to appear in Optics Letter

    Development of a Zoo Walk Navigation System using the Positional Measurement Technology and the Wireless Communication Technology

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    In this article, we propose and evaluate a Zoo Walk Navigation System consistings of the Animal Contents Registering and Editing Web Management System and the Animal Contents Browsing and Acquiring Smartphone Application. The Animal Contents Registering and Editing Web Management System for zoo staff enables to register/edit various animal contents. Thereby, this web management system provides real-time and flesh zoo information to the Animal Contents Browsing and Acquiring Smartphone Application. On the other hand, the Animal Contents Browsing and Acquiring Smartphone Application for zoo visitors enables to browse various animal contents which zoo staff registered through the Animal Contents Registering and Editing Web Management System. The Animal Contents Browsing and Acquiring Smartphone Application has the animal guide browsing function, the animal quiz function, the beacon notification browsing function, the zoo map navigating function, and the AR camera function. Zoo visitors can enjoy a zoo park using this smartphone application. This system is the new type navigation system which zoo staff can renew contents to avoid contents obsolescence. And, this system always provides new information to zoo visitors in real time by the beacon notification function

    変形性関節症に関連する遺伝子多型についてのシステマティックレビュー

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    Osteoarthritis (OA) is the complex multifactorial disease of which the etiology is not yet well defined, and recently increasing attention has focused on the genetic risk factors of OA. The purpose of this study was to analyze the published literature on the association between genetic polymorphisms and OA by a systematic review method. Papers published from 1995 to March 2005 with the keywords cytokines, polymorphisms and OA, as well as papers among the references in these papers were obtained from Plumbed. The inclusion criteria were papers on the relationship between genetic polymorphisms of the Interleukin (IL)-1, 1L-1 receptor antagonist (RA), or the Tumor Necrosis Factor (TNF)-alpha and OA, and the paper includes retrospective studies that compare the prevalence of genetic polymorphisms of OA and healthy controls. Studies with fewer than ten subjects were excluded. Only three papers met the selection criteria, and these were reviewed. Evidence-based medicine data tables were drawn for each of the three papers respectively. There were significant differences (P=0.0007) in the frequencies of the T allele of IL-1β C3954T in the genetic polymorphism between OA patients with total hip or knee replacement and healthy controls. The evidence from the articles reviewed indicated a statistically significant correlation between OA and some specific polymorphisms of IL-1, but some of the reports showed bidirectional results. Further rigorous studies based on well-defined disease and control criteria will be required to contribute to the prevention and management of OA

    Restoration of E-cadherin expression by selective Cox-2 inhibition and the clinical relevance of the epithelial-to-mesenchymal transition in head and neck squamous cell carcinoma

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    BACKGROUND: The epithelial-to-mesenchymal transition (EMT) accompanied by the downregulation of E-cadherin has been thought to promote metastasis. Cyclooxygenase-2 (Cox-2) is presumed to contribute to cancer progression through its multifaceted function, and recently its inverse relationship with E-cadherin was suggested. The aim of the present study was to investigate whether selective Cox-2 inhibitors restore the expression of E-cadherin in head and neck squamous cell carcinoma (HNSCC) cells, and to examine the possible correlations of the expression levels of EMT-related molecules with clinicopathological factors in HNSCC. METHODS: We used quantitative real-time PCR to examine the effects of three selective Cox-2 inhibitors, i.e., celecoxib, NS-398, and SC-791 on the gene expressions of E-cadherin (CDH-1) and its transcriptional repressors (SIP1, Snail, Twist) in the human HNSCC cell lines HSC-2 and HSC-4. To evaluate the changes in E-cadherin expression on the cell surface, we used a flowcytometer and immunofluorescent staining in addition to Western blotting. We evaluated and statistically analyzed the clinicopathological factors and mRNA expressions of Cox-2, CDH-1 and its repressors in surgical specimens of 40 patients with tongue squamous cell carcinoma (TSCC). RESULTS: The selective Cox-2 inhibitors upregulated the E-cadherin expression on the cell surface of the HNSCC cells through the downregulation of its transcriptional repressors. The extent of this effect depended on the baseline expression levels of both E-cadherin and Cox-2 in each cell line. A univariate analysis showed that higher Cox-2 mRNA expression (p = 0.037), lower CDH-1 mRNA expression (p = 0.020), and advanced T-classification (p = 0.036) were significantly correlated with lymph node metastasis in TSCC. A multivariate logistic regression revealed that lower CDH-1 mRNA expression was the independent risk factor affecting lymph node metastasis (p = 0.041). CONCLUSIONS: These findings suggest that the appropriately selective administration of certain Cox-2 inhibitors may have an anti-metastatic effect through suppression of the EMT by restoring E-cadherin expression. In addition, the downregulation of CDH-1 resulting from the EMT may be closely involved in lymph node metastasis in TSCC

    Sr Isotopic Composition of NIES Certified Reference Material No. 28 Urban Aerosols

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    An interlaboratory study of the National Institute for Environmental Studies (NIES) certified reference material (CRM) No. 28 Urban Aerosols collected from the filters of a central ventilating system in a building in the Beijing city center from 1996 to 2005 was performed to obtain an information value of the Sr isotopic composition. The Sr isotopic composition was measured using multi-collector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) to confirm the CRM’s within- and between-bottle homogeneity, and the results showed a 87Sr/86Sr ratio of 0.710227 ± 0.000019 (2SD, n = 18). The Sr isotopic compositions were intercompared using thermal ionization mass spectrometry (TIMS), which showed good agreement with values obtained at NIES. Subsequently, a consistent 87Sr/86Sr ratio was observed between two dissolution (hotplate vs. high-pressure bomb) and Sr separation (Sr spec resin vs. cation exchange resin) methods. To validate and reproduce the accuracy of our analytical methods, the Sr isotopic compositions of secondary reference materials, JB-1b and JA-2, were also measured. Our results showed that NIES CRM No. 28 is appropriate for the quality control of Sr isotope measurements of particulate matter analyses for environmental and geochemical studies

    ショウワキチ マイクロパルスライダー ニヨッテ カンソク サレタ ヒチケイセイ カンセイ ジュウリョクハ キゲン ノ ナンキョク キョクセイソウケン クモ

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    昭和基地に設置されたマイクロパルスライダー(MPL)により下部成層圏高度領域において極成層圏雲(PSC)が観測された.ラジオゾンデで観測されたPSCの出現高度における気温は氷の露点温度より約4度低く,提唱されている氷粒子生成温度とほぼ一致している.また,PSCの散乱強度は十分大きく,このPSCは氷粒子からなるType IIと分類された.観測されたPSCは温度の高度分布に対応し,温度極小高度を中心にして縞状に存在している.出現高度は時間とともに1日あたり~ 2 km降下している.温度極小は約4 kmの幅で4箇所存在し,それぞれの温度極小高度にPSCが現れている.ラジオゾンデで観測された風向風速の高度分布の解析から,この温度極小が非地形性の慣性重力波によることが示された.この種の重力波がPSCの生成に重要な役割を果たしている可能性が示唆された.PSCの出現に必要な気温低下が地形に制限されないため,非地形性慣性重力波が南北両極上空のPSC粒子生成に広く寄与している可能性が示唆された.Type II Polar Stratospheric Clouds (PSCs) were observed by micropulse lidar (MPL) at Syowa Station in the Antarctic on 30 June and on 1 July 2001. The vertical profiles of the PSCs had a wavy structure that was synchronized with the temperature fluctuations. A wave analysis using radiosonde data shows that the wavy fluctuations were associated with an inertia gravity wave that was not forced by ground topography, but probably by spontaneous adjustment in association with synoptic-scale wave-breaking processes in the upper troposphere. It is suggested that the observed PSCs were generated under the low-temperature conditions induced by these waves and that such gravity waves generated by spontaneous adjustment of large-scale fields can be more important to the formation of PSC particles, in both the Antarctic and Arctic stratospheres, than topographically forced gravity waves, because the former are not fixed to the ground topography

    Pretreatment neutrophil count as an independent prognostic factor in advanced non-small-cell lung cancer: An analysis of Japan Multinational Trial Organisation LC00-03

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    We examined the impact of pretreatment neutrophil count on survival in patients with advanced non-small-cell lung cancer (NSCLC). A total of 388 chemo-naive patients with stage IIIB or IV NSCLC from a randomised controlled trial were evaluated. The effects of pretreatment peripheral blood neutrophil, lymphocyte and monocyte counts and neutrophil-lymphocyte ratio on survival were examined using the proportional hazards regression model to estimate hazard ratios after adjustment for covariates. The optimal cut-off value was determined by proportional hazards regression analysis with the minimum P-value approach and shrinkage procedure. After adjustment for prognostic factors, the pretreatment elevated neutrophil count was statistically significantly associated with short overall (P = 0.0008) and progression-free survival (P = 0.024), whereas no association was found between prognosis and lymphocyte or monocyte count. The cut-off value selected for neutrophil count was 4500 mm-3 (corrected hazard ratio, 1.67; 95% confidence interval (CI), 1.09-2.54). The median survival time was 19.3 months (95%CI, 16.5-21.4) for the low-neutrophil group (≥4500 mm-3, n = 204) and was 10.2 months (95%CI, 8.0-12.3) for the high-neutrophil group (≥4500 mm-3, n = 184). We confirmed that pretreatment elevated neutrophil count is an independent prognostic factor in patients with advanced NSCLC receiving modern chemotherapy. Neutrophil count is easily measured at low cost, and it may be a useful indicator of patient prognosis
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