著者

Tomohito Hamazaki Harumi Okuyama Akira Tanaka Yasuo Kagawa Yoichi Ogushi Rokuro Hama

出版者

Japan Society for Lipid Nutrition

雑誌

脂質栄養学 (ISSN:13434594)

巻号頁・発行日

vol.21, no.1, pp.67-75, 2012 (Released:2012-04-29)

被引用文献数

1

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Almost all Japanese epidemiological studies showed that all-cause mortality was lower in subjects with high serum total or LDL-cholesterol levels. Studies showing the disadvantage of high cholesterol levels included or were likely to include more participants with FH than in the general Japanese population. This also explains why epidemiological studies with elderly people are not able to detect any disadvantage of high cholesterol levels; groups of elderly subjects contain a smaller proportion of vulnerable FH patients who die earlier than those without FH. Meta-analyses of the effects of statins were used to indicate the favorable effects of these drugs, which might be considered as proof that cholesterol has unfavorable effects. However, the absolute effect size of statins on all-cause mortality is rather small, if any. Moreover, studies included in meta-analyses of statins were performed before the new clinical research regulation came into effect in 2005-2006 in the EU, which required clinical trial results to be published even if the data were not favorable for the tested drugs (BJOG 2007; 114: 917, http://www.bjog.org/view/0/index.html). Considering the fact that placebo-controlled clinical trials performed after the new regulation were mostly negative (J Lipid Nutr 2010; 19: 65, http://www.jstage.jst.go.jp/article/jln/19/1/65/_pdf/-char/ja/), the results published before the regulation were questionable and should not be used as the basis for recommendations for treatment with cholesterol-lowering medications. Because the relative risks of high cholesterol for CHD vary from 5, administering cholesterol-lowering medications to all Japanese individuals equally is not rational; at least women and elderly men need to be carefully re-examined because no or little positive associations between plasma cholesterol and CHD mortality rates have been reported in these groups.

著者

Yoshinao ISOBE Hisabumi HATSUGAI Akira TANAKA Yutaka OIWA Takanori AMBE Akimasa OKADA Satoru KITAMURA Yamato FUKUTA Takashi KUNIFUJI

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E102-A, no.2, pp.325-335, 2019-02-01

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This paper presents a formal approach for generating train timetables in a mesoscopic level that is more concrete than the macroscopic level, where each station is simply expressed in a black-box, and more abstract than the microscopic level, where the infrastructure in each station-area is expressed in detail. The accuracy of generated timetable and the computational effort for the generation is a trade-off. In this paper, we design a formal mesoscopic modeling language by analyzing real railways, for example Tazawako-line as the first step of this work. Then, we define the constraint formulae for generating train timetables with the help of SMT (Satisfiability Module Theories)-Solver, and explain our tool RW-Solver that is an implementation of the constraint formulae. Finally, we demonstrate how RW-Solver with the help of SMT-Solver can be used for generating timetables in a case study of Tazawako-line.

著者

Akira Tanaka Reynald Affeldt Jacques Garrigue

出版者

Information Processing Society of Japan

雑誌

Journal of Information Processing (ISSN:18826652)

巻号頁・発行日

vol.26, pp.54-72, 2018 (Released:2018-01-15)

参考文献数

30

被引用文献数

4

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Our goal is the production of formally-verified pieces of low-level code. Low-level code is typically written in C, so as to enable efficient manipulation of data at the bit-level and easy access to built-in features of CPUs. Proof-assistants arguably provide the most rigorous approach to formal verification of computer programs. Unfortunately, they only allow for extraction of runnable code in high-level languages such as ML. Of course it is possible to embed C snippets into ML programs, but this results in a complicated extraction process and the performance of the output program becomes difficult to anticipate. In this paper, we propose a new code generation scheme for the Coq proof-assistant that directly generates provably-safe C code. It is implemented in the form of plugins. The generation of C source code is done by a plugin performing beforehand monomorphization of Coq programs. The correctness of monomorphization can be proved within Coq. Code generation allows for user-guided changes of data structures. It is therefore possible to do formal verification using proof-friendly data structures, while enjoying optimized C representations in the output code. In order to ensure the safety of this transformation, we propose a new customizable monadification algorithm in the form of another plugin. Using monadification, one can ensure by the insertion of the right monads the preservation of critical invariants, such as the absence of overflows or complexity properties. We provide several examples to illustrate our approach, including a realistic use-case: the rank algorithm from succinct data structures.

著者

Akio TSUCHIYA Akira TANAKA Niro HIGUCHI

出版者

The Association of Japanese Geographers

雑誌

地理学評論 (ISSN:13479555)

巻号頁・発行日

vol.78, no.12, pp.794-811, 2005-10-01 (Released:2008-12-25)

参考文献数

51

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Soil CO2 concentration and microclimatic parameters were measured at a primary forest and grassland in dry season (August to September 2003) and rainy season (March 2004) in central Amazonia in order to investigate the effects of infiltration of rainfall and evaporation of soil water upon the changes in soil CO2. The CO2 temporarily increased with infiltration, and decreased after soil water descended downward. Then, the increase and decrease moved to deeper soil. This phenomenon was found at both a primary forest and a grassland in the rainy season, and was found in the dry season as well at primary forest. At the grassland in dry season, the soil moisture change was positive during daytime, while the CO2 concentration change was negative. During nighttime, in contrast, the soil moisture change was negative and the concentration change was positive. It was estimated that the fluctuation of radiation between day and night reversed the relative position of soil water and CO2 in the soil. In the rainy season, there was not a large difference in the surface soil concentration (10-30cm: 20, 000-25, 000ppm) between the sites, while in dry season the concentration at the grassland was quite low (2, 500-2, 600ppm). From these findings, it was estimated that the soil CO2 was emitted or the root respiration was quitted due to the withering of herbs on the grassland in the dry season. In either case, it is thought that the decrease in soil CO2 was brought about by the exposure of naked land due to the disappearance of forest canopy.

著者

Akira TANAKA Kyohei YAMASHITA

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.42, no.8, pp.1585-1588, 1978 (Released:2008-11-27)

参考文献数

24

被引用文献数

4

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α-Methylene γ- and δ-lactones can be prepared in fair yields by a two step procedure involving formation of the a-hydroxymethylene or α-ethoxyoxalyl sodio derivatives of γ- or δ-lactones followed by their condensation with formaldehyde.