470 research outputs found

    Reversion-inducing cysteine-rich protein with kazal motifs and matrix metalloproteinase-9 are prognostic markers in skull base chordomas

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    Prognosis of chordomas is difficult to predict based solely on histological findings. The purpose of this study was to assess expressions of reversion-inducing cysteine-rich protein with kazal motifs (RECK) and matrix metalloproteinase (MMP)-2, MMP-9 in skull base chordomas and to find out their correlations to outcome. Immunohistochemical study was performed in 19 samples (initial, n = 11; recurrent, n = 8) from 11 patients. The correlations among expression of RECK, MMP-2, MMP-9, and their prognostic values were analyzed. Significant correlation between RECK and MMP-9 was found, but there was no correlation found between MMP-2 and MMP-9. Higher MMP-9 expression significantly influenced outcome. Furthermore, MMP-9/RECK ratio showed significant correlation to outcome, showing their inverse relationship in the disease progress of skull base chordoma. RECK and MMP-9 can be valuable markers to predict prognosis in skull base chordomas.ArticleNEUROSURGICAL REVIEW. 33(2):167-173 (2010)journal articl

    歴史学者がおこなう「真正な実践」の解明 : 歴史教師による自律的な教材研究に向けて

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    本研究は,専門科学者がおこなう「真正な実践」の解明に向けたシリーズ研究のうち,知識の社会領域の中でも歴史学者の研究に注目し,「歴史学者ならではの学習過程とはどのようなものか」「その学習過程は,歴史教師が教材研究をおこなう上でどのように活かすことが可能か」を解明することが目的である。そのために,歴史学論文の構成・構造分析と論文著者へのインタビューをもとに,歴史学者の研究過程とその背景を分析する。これを,歴史学者ならではの学びの過程として読み替えていく。本稿では,近世史の視点から近代史の研究課題に挑んだ2008年の論文「地租改正における地価決定と収穫高-広島県恵蘇郡奥門田村を事例として-」とその著者である歴史学者の中山富広を研究対象とした。結果,論文執筆に際しての研究過程は,「研究デザインの構築」「研究デザインに基づく実証研究」「研究デザインの省察と意義付け」という段階を経ていることが明らかになった。そして,論文執筆の背景にある学びとしては「研究経験」「専門領域や周辺領域に関する学界動向の学び」「他者との交流」「教育経験」という側面が確認できた。ここから学びとった概念や方法を,自分なりに再構成し,他の研究者共同体や自分の研究者共同体に適用するというアプローチが繰り返しおこなわれていた。以上を踏まえて,歴史学者の学習過程を理解する上で求められる視点として,「活用されている史料と解釈の対応関係を把握すること」「解釈を論文として説明する際に活用されている語彙の意味を理解すること」「論文の生成される文脈,研究史を学習すること」の3点を提案した。歴史学者の真正な学びとは,史料,史料を説明するための語彙,語彙を生み出す背景にある研究史に関わったものである。これらを読み解くことで,歴史教師は歴史学者の論文を深く理解し,教材研究に活かすことができる。The current study focused on a research study conducted by a historian, and aimed to understand “What are the aspects of learning process that are unique to historians?” and “How can we apply the processes to a history teacher’s reading of a history research paper for the purpose of teaching material studies?” For that purpose, the current manuscript analyzed the processes and the background of writing a history research paper through analyses of the composition and construction of a history paper and an interview with its author. Then, we attempted to translate this into a learning process unique to a history researcher. The current manuscript selected to study “Land Price Appraisal and Crop Harvest in Land Tax Reform: Case Study of Okumonde Village, Eso County, Hiroshima Prefecture,” a history research paper written in 2008 that examined a contemporary historical research topic of using a modern history viewpoint, authored by Dr. Tomihiro Nakayama. The analyses indicated that the research processes went through stages of “construction of a research design,” “empirical study based on the research design,” and “reflection on the research design and interpretation.” Beyond the paper writing, important skills also included “research experience,” “learning of the trends of the field and its associated fields,” “interaction with others,” and “teaching experience.” The history researcher reconstructed the concepts and methods from such learning in his own way, and applied the findings within his and colleagues’ research communities. Based on these findings, three viewpoints necessary in understanding the learning process of a historian included, “understanding of the relationship between historical resources and its interpretation,” “understanding of the vocabulary used in the paper that describes the interpretation of historical resources,” and “studying the context and research history that produced a particular research paper.” Authentic learning for a historian concerns historical resources, vocabulary to explain the resources, and research history that generated the vocabulary. By understanding these elements, a history teacher can attain deep understanding of a history research paper and apply it to studying of teaching materials

    Topology analysis of data space using self-organizing feature map

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    In order to analyze the topological structure of the data space using Kohonen\u27s self-organizing feature map (SOFM), a criterion is discussed. The Euclidian distance between the reference vector and the data, the number of the reference vectors and the topology preserving measure are taken into account, and are combined in a unified criterion. Through computer simulation, it is confirmed that goodness of the different reference topologies, that is dimensions, can be clearly discriminated regardless the parameters. Thus, the unified criterion makes it possible to analyze the essential data space topology

    Thin Sea-Ice Thickness as Inferred from Passive Microwave and In Situ Observations

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    Since microwave radiometric signals from sea-ice strongly reflect physical conditions of a layer near the ice surface, a relationship of brightness temperature with thickness is possible especially during the early stages of ice growth. Sea ice is most saline during formation stage and as the salinity decreases with time while at the same time the thickness of the sea ice increases, a corresponding change in the dielectric properties and hence the brightness temperature may occur. This study examines the extent to which the relationships of thickness with brightness temperature (and with emissivity) hold for thin sea-ice, approximately less than 0.2 -0.3 m, using near concurrent measurements of sea-ice thickness in the Sea of Okhotsk from a ship and passive microwave brightness temperature data from an over-flying aircraft. The results show that the brightness temperature and emissivity increase with ice thickness for the frequency range of 10-37 GHz. The relationship is more pronounced at lower frequencies and at the horizontal polarization. We also established an empirical relationship between ice thickness and salinity in the layer near the ice surface from a field experiment, which qualitatively support the idea that changes in the near-surface brine characteristics contribute to the observed thickness-brightness temperature/emissivity relationship. Our results suggest that for thin ice, passive microwave radiometric signals contain, ice thickness information which can be utilized in polar process studies

    High-sensitivity quantitative analysis reveals the non-linear relationship between the dose and deposition of diphenylarsinic acid in the rat central nervous system following its subchronic exposure

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    In the year 2003, the residents of Kamisu, Japan, were exposed to pentavalent organic arsenic diphenylarsinic acid (DPAA[V]) via their normal drinking water. Following the exposure, they developed cerebellar and brainstem symptoms. Although the relatively high dose of DPAA(V) is assumed to have caused their symptoms, the relationship between the exposed dose of DPAA(V) and the level of their deposition in the central nervous system (CNS) remains unclear. Using liquid chromatography–tandem mass spectrometry, we examined the deposition of DPAA(V) and its pentavalent metabolites in the CNS tissues of Crl:CD(SD) rats following the administration of DPAA(V) for 28 days. We found that the concentrations of DPAA(V) in the CNS were very high, given a dose of 5.0 mg/kg/day. However, very low concentrations of DPAA(V) were detected at a dose of 0.3 or 1.2 mg/kg/day, suggesting the absence of a linear dose-response relationship between the dose and deposition of DPAA(V). We also found that this non-linear relationship was commonly observed in various non-CNS tissues, including the excretory system. Our study showed for the first time the exact relationship between the dose and tissue deposition of the organic arsenic following its subchronic administration

    Physical and Radiative Characteristics and Long Term Variability of the Okhotsk Sea Ice Cover

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    Much of what we know about the large scale characteristics of the Okhotsk Sea ice cover comes from ice concentration maps derived from passive microwave data. To understand what these satellite data represents in a highly divergent and rapidly changing environment like the Okhotsk Sea, we analyzed concurrent satellite, aircraft, and ship data and characterized the sea ice cover at different scales from meters to tens of kilometers. Through comparative analysis of surface features using co-registered data from visible, infrared and microwave channels we evaluated how the general radiative and physical characteristics of the ice cover changes as well as quantify the distribution of different ice types in the region. Ice concentration maps from AMSR-E using the standard sets of channels, and also only the 89 GHz channel for optimal resolution, are compared with aircraft and high resolution visible data and while the standard set provides consistent results, the 89 GHz provides the means to observe mesoscale patterns and some unique features of the ice cover. Analysis of MODIS data reveals that thick ice types represents about 37% of the ice cover indicating that young and new ice represent a large fraction of the lice cover that averages about 90% ice concentration, according to passive microwave data. A rapid decline of -9% and -12 % per decade is observed suggesting warming signals but further studies are required because of aforementioned characteristics and because the length of the ice season is decreasing by only 2 to 4 days per decade

    Identifying important aspects of quality of life among Muslims with hypertension in rural West Java, Indonesia

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    Hypertension almost invariably impacts people’s quality of life (QOL). The WHO Quality of Life-BREF instrument (WHOQOL-BREF) is used widely in high-income countries and is comprised of physical, psychological, social and environmental domains. Few studies have measured QOL of people with hypertension in rural areas in low- and middleincome countries, including Indonesia. Our study aims were: 1) to assess whether WHOQOL-BREF is suitable for studying QOL among rural Muslim Indonesians with hypertension, and 2) to describe the characteristics of rural Muslim Indonesians’ QOL. In 2014, we conducted a cross-sectional survey of QOL among 447 residents of an economically stressed rural district in West Java. To assess WHOQOL-BREF’s goodness of fit, we performed structural equation modeling. We calculated Cronbach’s alpha to assess internal consistency reliability. Independent t-tests and one-way ANOVAs were used to compare differences between socio-demographic groups. Participants were mostly women (77%). Mean age was 54 and 24% were widows/widowers. Most (62%) had less than primary level education. Regarding measures of goodness of fit, only root mean square error of approximation reached a marginally acceptable level. Cronbach’s alpha for the overall scale was fairly high (0.893). Psychological QOL received the highest mean domain score (13.8). Environmental QOL received the lowest (12.6). The highest mean item score was for mobility. Financial status, access to information, and leisure received the lowest mean item scores. Domain scores differed by socioeconomic status. Low QOL on one or more domains was associated with lower education, being a widow/widower, and living in a remote area. Since the model showed that WHOQOL-BREF did not achieve desired levels on two of three goodness-of-fit indexes, other aspects of the participants’ QOL may have gone unmeasured. When providing healthcare services to Muslim patients with hypertension in rural Indonesia, planners and providers should attend to aspects of QOL identified in this study
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