316 research outputs found
Variable-Length Coding with Cost Allowing Non-Vanishing Error Probability
We derive a general formula of the minimum achievable rate for
fixed-to-variable length coding with a regular cost function by allowing the
error probability up to a constant . For a fixed-to-variable
length code, we call the set of source sequences that can be decoded without
error the dominant set of source sequences. For any two regular cost functions,
it is revealed that the dominant set of source sequences for a code attaining
the minimum achievable rate with a cost function is also the dominant set for a
code attaining the minimum achievable rate with the other cost function. We
also give a general formula of the second-order minimum achievable rate.Comment: 7 pages; extended version of a paper accepted by ISITA201
Bioenergy production and food security in Africa
Food and energy insecurities are the two greatest problems in Africa. Per capita energy consumption in Africa is less than 10% of that of United States of America while 18 out of 23 countries where starvation and malnutrition are most severe in the world are in Africa. Although various African governments have been making efforts to boast agricultural productivity, crop yields remain very low. Most governments do not even have accurate statistics on the number, location and types of crops produced by smallholder farmers that produce more than 80% of foods in Africa. This makes it very difficult to plan and implement any government support to the farmers. Sub-Saharan African countries have very high potential for production of different forms of bioenergy because the climatic conditions favour production of many energy crops. The big question has always been whether to produce bioenergy from food crops, especially in Africa with high acute food shortages. Large scale production of bioenergy may lead to competition with food crops for land, labour and other agricultural inputs. However, data from various sources indicate that Africa has abundant and underutilized arable land which can be effectively used for mass production of energy crops. Furthermore, shortage of labour cannot be a problem given the present very high rate of unemployment in most African countries. The benefits of bioenergy production in Africa outweigh the possible adverse effects on food security. Bioenergy production will create demand for, and stabilize the prices for crops, thereby increasing the earning of the farmers. This will in turn, facilitate industrialization in other sectors of economy through provision of affordable, renewable and clean energy. In order to minimize possible negative effects of bioenergy production on food security, land allocation for energy crop production can be regulated. Energy security cannot be separated from food security and the two should be seen as complimentary rather than as competitors.Key words: Bioenergy production, food security, energy
A Case of Acquired Leucoderma, Associated with Hashimoto's Thyroiditis
A 67-year-old female diagnosed as Hashimoto's thyroiditis in company with acquired leucoderma was reported. She first noticed the enlarged thyroid at the age of 36, and thereafter leucoderma made its appearance 30 years later. Though a significant association between these two diseases has been found in the literature thus far and they are considered to be of autoimmune origin, their coexistence is not so common clinically. In spite of PUVA treatment, a benefit effect was not obtained completely
A Case of 48, XYY, +21
A 3 month-old boy with a karyotype of 48, XYY, + 21 is reported. The patient had the typical features of Down syndrome and normal male genitalia.
Analysis of Q- and R-banded chromosome heteromorphisms of the patient and the parents showed that two of the three chromosomes 21 in the patient originated as a result of failure of the paternal second meiotic division. Therefore both additional chromosomes in the patient resulted from nondisjunction at paternal meiosis II
シェーグレン症候群患者唾液線組織におけるEpstein-Barrウイルス由来核内小RNAの発現
取得学位 : 博士(医学), 学位授与番号 : 医博甲第1109号, 学位授与年月日:平成6年3月31日,学位授与年:199
嚢胞腎遺伝子産物Polycystin-2の分子電気生理学的機能解析
金沢大学附属病院研究代表者らは、PKD1の遺伝子産物Polycystin-1の機能測定系を確立した。この系は、全長ないし部分的なPKD1のcDNAを発現させ、神経細胞のCaおよびKチャンネルをセンサーとして利用して、種々の刺激などの影響を観るものである。この系を用いて、Polycystin-1がG(i/o)タイプのG蛋白を活性化させる機能があることを明らかにした。この効果はRGS蛋白には依存しなかった。さらに、Polycystin-2の全長cDNAを共発現させると、Polystin-1のG蛋白活性効果が消失することが明らかとなった。これらの結果は、通常複合体を形成しているPolycystin-1とPolycystin-2の何れかの遺伝子の異常により、G蛋白が活化されて細胞の分裂を促し、嚢胞が形成されていることを強く示唆している。また、PKD2と相同性の高いPKDLの遺伝子産物Polycystin-Lの生体内での局在を、抗Polycystin-L作成して検討した。さらに、PKDLをHEK293細胞に発現させた。抗PCL抗体を用いた免疫染色にて、PCLは細胞膜表面に存在することが明らかとなり、またパッチクランプ法によりPCLには、自発活性が認められた。Na+、Cs+、K+のイオン透過性は1.1:1:1.2であり、PCLは、カルシウム透過型非選択的カチオンチャンネルであることが明らかとなった。また外液のカルシウムにより、コンダクタンスの減少が認められた。HEK細胞を用いた系では、Xenopus oocytesを用いた以前の報告で認められた、カルシウムによるチャンネルの活性化は認められなかった。研究課題/領域番号:12770581, 研究期間(年度):2000-2001出典:「嚢胞腎遺伝子産物Polycystin-2の分子電気生理学的機能解析」研究成果報告書 課題番号 12770581(KAKEN:科学研究費助成事業データベース(国立情報学研究所))(https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-12770581/)を加工して作
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