Epimorphisms between 2-bridge link groups

We give a systematic construction of epimorphisms between 2-bridge link groups. Moreover, we show that 2-bridge links having such an epimorphism between their link groups are related by a map between the ambient spaces which only have a certain specific kind of singularity. We show applications of these epimorphisms to the character varieties for 2-bridge links and pi_1-dominating maps among 3-manifolds.Comment: This is the version published by Geometry & Topology Monographs on 29 April 200

Creation of Mo/Tc@C60 and Au@C60 and molecular-dynamics simulations

The formation of middle- and/or high-weight atom (Mo, Au)-incorporated fullerenes was investigated using radionuclides produced by nuclear reactions. From the trace radioactivities of ⁹⁹Mo/⁹⁹mTc or ¹⁹⁴Au after high-performance liquid chromatography, it was found that the formation of endohedral and/or heterofullerene fullerenes in ⁹⁹Mo/⁹⁹mTc and ¹⁹⁴Au atoms could occur by a recoil process following the nuclear reactions. Furthermore, the ⁹⁹mTc (and ¹⁹⁴Au) atoms recoiled against β-decay remained present inside these cages. To confirm the produced materials experimentally, ab initio molecular dynamics (MD) simulations based on an all-electron mixed-basis approach were performed. The possibility of the formation of endohedral fullerenes containing Mo/Tc and Au atoms is verified; here, the formation of heterofullerenes is excluded by MD simulations. These findings suggest that radionuclides stably encapsulated by fullerenes could potentially play a valuable role in diagnostic nuclear medicine

緑茶の香気に関する研究(B. 生活科学)

The head space vapors of four kinds of green tea (Sen-cha, Gyokuro, Ten-cha and Mat-cha) were analyzed by gas chromatography. The chromatographic pattern of Sen-cha was different from those of the others, although the separation of the volatile compounds of the vapor was not enough. Organoleptic detection of tea aroma was performed under the gas chromatographic conditions and then four kinds of odor were recognized. The denaturation of tea aroma was also studied. It was observed that the bad effect on the tea was multiplied by the conditions of high moisture and high temperature

ショウガ・プロテアーゼの精製と安定化(B. 生活科学)

ショウガの根に含まれる蛋白質加水分解酵素をアセトン処理, りん酸緩衝液抽出, CM-セルロースクロマトグラフィー, Bio-Gel P-100によるゲルクロマトグラフィーなどの処理により高純度に精製した.この際プロテアーゼの自己消化防止剤(安定化剤)として, HgCl_2とPCMBの水銀剤を使用しその効果を比較検討したが, HgCl_2を反応させScheme 1の方法で精製した酵素は, 二量体の酵素が生成していて, Bio-Gel P-100のクロマトグラム上で高分子の不純物と重り合った.PCMBで安定化した酵素をCM-セルロースクロマトグラフィーおよびBio-Gel P-100のゲルクロマトグラフィーにかけて得た標品は最も比活性も大きく純度の高いものであった.この標品は安定化剤を使用しないで精製し得られた標品の約6倍活性の強いものであった.またこの精製プロテアーゼのBio-Gel P-100による分子量の測定によると, 2万9千であって, この値はSDS-スラブ-ポリアクリルアミドゲル電気泳動によって求めた前回の実験値とよく一致した.Ginger protease which exists in the rhyzome (Zingiber officinale roscoe) was purified by chromatography on CM-cellulose and gel filtration on Bio-Gel P-100. In the course of the purification, HgCl_2 or p-chloromercuribenzoic acid (PCMB) was used as a stabilizing agent for the protease. It was shown that the protease stabilized with HgCl_2 formed a dimer complex which could not be separated from the higher molecular contaminant. The protease activity of the preparation stabilized with PCMB and purified by the chromatography was as high as 6-fold of that without PCMB. From the result of gel filtration on Bio-Gel P-100,the molecular weight of this purified protease was estimated to be about 29,000,which is the same as the value obtained previously by SDS slab-polyacrylamide gel electrophoresis

納豆菌の菌体外セルラーゼおよびキシラナーゼ(B. 生活科学)

納豆菌の菌体外セルラーゼを得るために各種液体培地で培養し, それらの滬液のCMCase活性を測定して検討した。その結果肉エキス, ペプトン, CMC, を含む培地で40℃2日間振盪培養すると最大の酵素活性を得ることができた。この酵素にはCMCaseだけでなくセルロース粉末分解活性も見られさらにキシラナーゼ活性がCMCase活性の約3倍も含まれることが明らかとなった。CMCase活性とキシラナーゼ活性とは今回は互いに分離することはできなかったがBio-Gel P-100によりそれぞれの比活性をかなり上昇させることができた。Cellulolytic activity was observed in the culture filtrate of Bacillus subtilis var. natto IFO 3335. The maximuin cellulolytic activity was obtained in the filtrate of two-days-cultured medium. This culture medium filtrate also contained an intense xylanase activity. The purification of these extracellular enzymes in the culture medium was tried by the gel chromatography of Bio-Gel P-100 and the specific activities of the enzymes was appreciably increased, although the isolation of the xylanase fraction from the cellulolytic activity fraction was not attained

鶏卵 Flavoprotein のアガロースゲル(セファロース 4B)への固定化(B. 生活科学)

Immobilization of Egg White and Egg Yolk Flavoproteins on Agarose-gel Beads (Sepharose 4B) was tried by the CNBr activation method. The immobilized egg white flavoprotein had 63% of riboflavin-binding capacity of that of native flavoprotein, and the immobilized egg yolk flavoprotein had 74%. Both of the immobilized flavoproteins were resistant against a denaturing reagent, 2 M or 6 M urea. These immobilized apoproteins are useful as column packing materials for the determination of free and bound riboflavins in various materials and may be used for various purposes in laboratory or industrially owing to their stability

緑茶の香気に関する研究 (II) : Head Space Vapor 中のイオウ化合物の分析(B. 生活科学)

緑茶のHead space vaporをPEG-6000の分離カラムでガスクロマトグラフ的に分析した。この条件では緑茶の香気成分として知られているn-吉草酸, サリチル酸メチル, アセトフェノン, カプロン酸, ジメチルサルファイド, イソ吉草酸アルデヒド, ゲラニオール, ベンジルアルコール, リナロールなどを群別には分離できたが緑茶の新鮮感に関与するジメチルサルファイドの定量には適当ではない。ジメチルサルファイドはイオウ系化合物であるので検出器としてFPDを用い1,2,3-TCEPを分離カラムとして緑茶のHead space vaporを分析した。その結果緑茶のHead space vapor中でイオウ系化合物はジメチルサルファイドが主なものであることが明らかになった。また玉露, 煎茶の各品質のものとジメチルサルファイドの量について比較したところ, その含量はほぼ緑茶の品質に比例していた。Sulfur compounds in the head space vapor from six kinds of green tea, Gyokuro and Sencha, were analyzed by gas chromatography with the flame photometric detector on a separation column of 1,2,3-TCEP. The major component of sulfur compounds in the head space vapor was identified as dimethyl sulfide. It was found that the content of dimethyl sulfide in the head space vapor was proportional to the organoleptic quality of the green tea, both Gyokuro and Sencha

Defective repair of radiation-induced DNA damage is complemented by a CHORI-230-65K18 BAC clone on rat chromosome 4

AbstractThe Long Evans cinnamon (LEC) rat is highly susceptible to X-irradiation due to defective DNA repair and is thus a model for hepatocellular carcinogenesis. We constructed a bacterial artificial chromosome (BAC) contig of rat chromosome 4 completely covering the region associated with radiation susceptibility. We used transient and stable transfections to demonstrate that defective DNA repair in LEC cells is fully complemented by a 200-kb BAC, CHORI-230-65K18. Further analysis showed that the region associated with radiation susceptibility is located in a 128,543-bp region of 65K18 that includes the known gene Rpn1. However, neither knockdown nor overexpression of Rpn1 indicated that this gene is associated with radiation susceptibility. We also mapped three ESTs (TC523872, TC533727, and CB607546) in the 128,543-bp region, suggesting that 65K18 contains an unknown gene associated with X-ray susceptibility in the LEC rat

塩蔵オキアミの利用に関する研究(第 1 報) : イソプロピルアルコール抽出法によるオキアミたん白質濃縮物 (KPC) およびエキスの調製(B. 生活科学)

An atempt was made to prepare the active krill protein concentrate (KPC) from salted antarctic krill by the extraction with isopropyl alcohol (iso-PrOH) without heat treatment. Salted krills were homogenized and filtered with Nylon gauze to remove the exoskeleton. Pink milky juice was mixed with an equal volume of iso-PrOH. As iso-PrOH does not miscible with salt solution, the miscella was separated into three layers by the centrifugation at 3,000rpm for 10min. The upper solvent layer contains lipids, pigments and other fat soluble vitamins. The krill protein was concentrated in the middle layer and non-protein nitrogen fraction, "the extractives", and the greater part of NaCl were recovered in the bottom aqueous layer. One of the typical KPC from salted krill contains 84% crude protein, 4% ash, 1% NaCl and 0.3% lipid and was rich in essential amino acids comparable to beef protein