タイヤトレッドゴムの氷上トライボロジー特性改善に関する研究

金沢大学工学部-10℃から0℃にかけて、氷上のゴムの摩擦は著しく低下することがすでに知られている。本研究において、各種ゴムの摩擦に及ぼす温度の影響について詳細に調べた。また、摩擦のデータが再現よく測定可能な-5℃の温度で、氷と各種ゴムとの摩擦速度及び接触圧力の影響について明らかにした。本研究は次の二つに大別できる。(イ)トレッド用ゴム試料として、天然ゴム(NR)とブタジエンゴム(BR)とをブレンドした標準ゴムと、それを発泡させた低硬度及び高硬度発泡ゴムに、短繊維入り低硬度発泡ゴムの4種の摩擦特性を調べる研究。(ロ)標準ゴムに、短繊維を3部、6部、10部充てんし、一軸方向に配向させた試料で、短繊維の配向方向と垂直なゴム表面と相手氷、水濡れ面、乾燥面とを摩擦し、短繊維強化の効果を調べる基礎研究。以上の二つの研究で得られた結論は、次の通りである。(1)-10℃〜0℃の氷の上でいずれのゴム試料とも単調に摩擦係数は低下する。乗用車で使用される0.2MPaの接触圧力では、短繊維入り低硬度発泡ゴムが、低硬度及び高硬度の発泡ゴムより摩擦係数は高く、標準ゴムは最低であった。しかし、1MPaの高圧力では、いずれのゴムも摩擦係数は低下し、その差はわずかであった。(2)-5℃の氷上の摩擦速度による摩擦係数の変化は、標準ゴムでは、1〜10cm/sの範囲でほぼ一定の比較的低い摩擦係数を示すが、20cm/s以上で急激に低下を示した。低硬度及び高硬度の発泡ゴムでは、標準ゴムよりやや高い摩擦係数を示し、高速度でいずれも低下する傾向がある。短繊維入り低硬度発泡ゴムでは、調べた各摩擦速度で摩擦係数は高く、30cm/s以上で低下した。(3)短繊維を配向させたゴム試料と-5℃との摩擦では、高速及び高圧力においても摩擦係数の低下は少ないという興味ある結果が得られた。It is well known that the rubber friction on ice decreases drastically at the temperature range from-10ﾟC to 0ﾟC.In this study, the effect of temperature on the friction for various rubber vulcanizates were investigated. The effects of sliding speed and contact pressure on the friction for rubbers on ice were also examined at-5ﾟC.In this study, two main investigations were carried out as follows :(a) Frictional properties of tire tread rubber specimens, such as normal specimen (natural rubber (NR)-butatiene rubber (BR) blend), low hardness porous rubber, high hardness porous rubber and low hardness porous rubber filled with short fiber.(b) Friction mechanism of short-fiber-reinforced-rubbers (SFRRs), which contained oriented short fibers of 3phr, 6phr, and 10phr respectively.From above two examinations, interesting results are obtained as follows :(1) The coefficient of friction on ice for each rubber specimen decreases drastically with increasing temperature at range from -10ﾟC to 0ﾟC.At the low contact pressure of 0.2MPa, low hardness porous rubber filled with short fiber shows the highest friction coefficient among the four rubber specimens. The normal specimen (NR/BR blend) shows the lowest value and, then the two porous rubbers are medium position. At the high contact pressure of 1MPa, every specimen shows low friction coefficient and the differences of the value for each rubber specimen is not distinguishable.(2) The friction coefficients for the normal specimen on ice at -5ﾟC are almost constant at sliding speed range from 1 to 10cm/s. However they decrease above the speed of 20cm/s. The low-and high-hardness porous rubbers show rather higher values compared with the normal specimen. The friction coefficient for the low hardness porous rubber filled with short fiber shows higher value in the range of sliding speed examined, and drops above 30cm/s. Therefore, the filled fiber have an effect to increase the friction coefficient on ice under wide range of sliding speed.(3) When SFRRs are rubbed against ice at -5ﾟC,interesting results are drawn that the friction coefficients are not reduced drastically even at high speed and high contact pressure.研究課題/領域番号:06650168, 研究期間(年度):1994 – 1995出典：研究課題「タイヤトレッドゴムの氷上トライボロジー特性改善に関する研究」課題番号06650168（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/report/KAKENHI-PROJECT-06650168/066501681995kenkyu_seika_hokoku_gaiyo/）を加工して作

雪氷路面におけるゴムの摩擦メカニズムに関する研究

金沢大学工学部0℃付近における氷上のゴムの摩擦係数は著しく低い。そのため、実用の自動車用タイヤにおいては重大な問題である。この0℃付近での摩擦係数を増大させるために、摩擦の掘り起こしの頃を利用したスパイクタイヤが実用化されている。しかし、このスパイクタイヤは路面の摩耗を生じさせるため、その改善が望まれている。スパイクピンの作用力が0℃よりも高い温度で弱まり、0℃以下の温度では通常の作用力を示す温度順応性スパイクタイヤの基礎実験を行い、すべり摩擦時の路面損傷を軽減できることがわかった。現在ではスパイクタイヤの製造禁止が行われるため、スタッドレスタイヤの基礎研究として氷とゴムとの摩擦が重要となってきた。そしてゴムと氷との摩擦係数に及ぼす温度、接触圧力、摩擦速度及びゴム材質の影響について研究を行い、以下の結果を得た。1.氷とゴムとの摩擦係数に及ぼす温度及び接触圧力の影響各ゴム試料とも-20℃及び-15℃では比較的高い摩擦係数を示すが、-10℃においては摩擦係数は著しく低下し、-5℃から0℃においては0.2以下という低い値を示した。さらに接触圧力の増大とともに摩擦係数は減少し、天然ゴム試料では0.8MPaのときの値は0.2MPaのときの約半分の摩擦係数である。2.氷とゴムとの摩擦係数に及ぼすゴム材質の影響天然ゴム及びブタジエンゴムと氷との摩擦を行ったところ、ブダジエンゴムに比べ天然ゴムの方が-20℃から-15℃にかけて摩擦係数は約2倍高い値を示したが、-5℃から0℃にかけてはあまり大きな差はみられず低い値を示した。この摩擦係数の違いは接触面におけるせん断強さの違いによるものと考えられる。The friction coefficient of rubber on ice is very low around 0 C. Tt is important problems for motorcars. To increase the friction coefficient aroud 0 C, studded tires utilizing the ploughing term of the friction have used. These studded tires damage road surfaces. Therefore it is desirable to reduce the road damage. A temperature adaptable studded snow tire has been developed and the frictional properties were examined on dry concrete surfaces and ice surfaces. A sheet of a temperature adaptable rubber was attached to the base of a spike pin. The operating force of the stud below 0 C is larger than that above 0 C. When used the temperature adaptable studded snow tire, the demage of road surface is minimized.Recently production of studded tire is going to forbit in Japan. Studies on the rubber friction on ice are important as a fundamental research.When rubbers were rubbed against ice, the effects of temperature, silding speed and base polymer were examined. The results obtained were as follows:(1) The effects of temperature and contact pressure on the friction coefficient of rubber on ice. The friction coefficients of rubber specimens were high at -20 C and -15 C. At -10 C the friction coefficients drastically decreased and they showed low values about 0.2 at the temperature range from -5 C to 0 C. The coefficient of friction decreased with increasing the contact pressure. The friction coefficient of a natural rubber vulcanizate under 0.8 MPA was half value compared to that under 0.2 MPA.(2) The influence of base polymer on the friction coefficient of rubber on ice. Natural rubber showed two times high friction coefficient at the temperature from -20 C to -15 C compared to butadiene rubber. However the difference of the two rubbers were not distinguished at the temperature range from -5 C to 0 C and they showed low value. The difference of the coefficient seems to be originated from the difference of their shear strengths at the contact area.研究課題/領域番号:62550648, 研究期間(年度):1987 – 1988出典：研究課題「雪氷路面におけるゴムの摩擦メカニズムに関する研究」課題番号62550648（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/report/KAKENHI-PROJECT-62550648/625506481988kenkyu_seika_hokoku_gaiyo/）を加工して作

高分子材料の摩耗粉生成機構に関する研究

金沢大学工学部研究課題/領域番号:X00095----165017, 研究期間(年度):1976出典：「高分子材料の摩耗粉生成機構に関する研究」研究成果報告書　課題番号X00095----165017（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-X00095----165017/）を加工して作

高分子材料の摩耗におよぼす温度の影響

金沢大学工学部研究課題/領域番号:X45210------5023, 研究期間(年度): 1970出典：研究課題「高分子材料の摩耗におよぼす温度の影響」課題番号 X45210------5023（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-X45210------5023/）を加工して作

Surgical treatment of bronchogenic carcinoma in patients over the age of 80 years old

From 1979 to 1986, pulmonary resection for bronchogenic carcinoma were performed in twelve patients over age 80. There were ten men and twowomen. The ages of the patients were 81 in three, 82 in three, 83 in four and 84 in two. The histologic cell types were adenocarcinoma in seven patients, squamous cell carcinoma in four, and large cell carcinoma in one. Eight patients were Stage I (T1 N0 M0 4 and T2 N0 M0 4) 3 were Stage III (T2 N2 M0 2 and T3 N1 M0 1) and one was Stage VI. The operative procedures undertaken were lobectomy in 5, segmentectomy in 3 and wedge resection in 4. Mediastinal nodes dissection was performed in 6 patients. There were ten curative resection and 2 were incurative. No operative deaths occured. 6 patients had dies, 2 of their disease, 2 of gastric cancer and 2 of other disease 5-50 months after operation. 6 patients are alive and well without disease 10-54 months after surgery. The results of this report indicate that pulmonary resections can be performed safely with low mortality and longterm survival in the patients over the age of 80. Because pulmonary resection for bronchogenic carcinoma remains the only effective form of therapy, the decision on whether to perform a pulmonary resections in patients over age 80 should be based not on age but on the patient\u27s cardiovascular status and pulmonary reserve

Association between reduced serum BDNF levels and insomnia with short sleep duration among female hospital nurses

Objective: Previous studies have suggested that brain-derived neurotrophic factor (BDNF) is associated with sleep regulation in humans. However, its relationship with self-reported sleep problems has not been clarified. The aim of the present study was to examine the association between serum BDNF levels and sleep problems among hospital nurses. Methods: Participants were enrolled from among nurses working at a general hospital in Tokyo, Japan. Data from 577 women (age: 35.45 ± 10.90 years) were analyzed. This cross-sectional survey was conducted from November to December 2015. Serum BDNF concentrations were evaluated. Participants completed a self-reported questionnaire on sleep including the presence or absence of insomnia symptoms (ie, difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening [EMA]), and sleep duration. Insomnia with short sleep duration (ISS) was defined as: DIS, or DMS, or EMA; and <6 h sleep duration. Results: Among 577 participants, 21.3% reported insomnia, 41.4% slept less than 6 h, and finally 12.5% suffered from ISS. Serum BDNF levels were significantly lower in subjects with ISS than in those without ISS. The serum BDNF levels in insomniacs were significantly lower than in non-insomniacs for short sleep duration (<6 h), while serum BDNF levels did not differ between insomniacs and non-insomniacs for normal sleep duration (≥6 h). Conclusion: This is the first documented study to indicate that ISS is associated with reduced serum BDNF levels. These results may lead to clarification of the underlying pathophysiological relationship between BDNF and poor sleep

Strain-Dependent Prion Infection in Mice Expressing Prion Protein with Deletion of Central Residues 91–106

Conformational conversion of the cellular prion protein, PrPC, into the abnormally folded isoform, PrPSc, is a key pathogenic event in prion diseases. However, the exact conversion mechanism remains largely unknown. Transgenic mice expressing PrP with a deletion of the central residues 91–106 were generated in the absence of endogenous PrPC, designated Tg(PrPΔ91–106)/Prnp0/0 mice and intracerebrally inoculated with various prions. Tg(PrPΔ91–106)/Prnp0/0 mice were resistant to RML, 22L and FK-1 prions, neither producing PrPScΔ91–106 or prions in the brain nor developing disease after inoculation. However, they remained marginally susceptible to bovine spongiform encephalopathy (BSE) prions, developing disease after elongated incubation times and accumulating PrPScΔ91–106 and prions in the brain after inoculation with BSE prions. Recombinant PrPΔ91-104 converted into PrPScΔ91–104 after incubation with BSE-PrPSc-prions but not with RML- and 22L–PrPSc-prions, in a protein misfolding cyclic amplification assay. However, digitonin and heparin stimulated the conversion of PrPΔ91–104 into PrPScΔ91–104 even after incubation with RML- and 22L-PrPSc-prions. These results suggest that residues 91–106 or 91–104 of PrPC are crucially involved in prion pathogenesis in a strain-dependent manner and may play a similar role to digitonin and heparin in the conversion of PrPC into PrPSc

Preferable Forms of Relaxation for Health Promotion, and the Association between Recreational Activities and Self-perceived Health

Little research has been done on the association between relaxation and health. In the present study, by conducting a nationwide cross-sectional survey, we aimed to obtain scientific data on the preferable forms of relaxation for health promotion, and to clarify the associations between specific recreational activities and self-perceived mental and physical health. We selected 4,000 households by stratified random sampling from across Japan in November 2009 and used the interview method to collect data (number of subjects:2,206). The questionnaire contained items on sleep, recreation status, recreational activities, and self-perceived mental and physical health status. We obtained responses from 1,224 adults (response rate:55.5%). Insufficient rest from sleep, short sleep duration (＜6h/day), ineffective use of free time, and less free time used for activities other than rest showed independent positive associations with poor mental and physical health. The results of the logistic regression analyses showed significantly low adjusted odds ratios with regard to the status of poor mental and physical health for outings/walking among men (0.33 [95% confidence interval;0.16-0.68] and 0.49 [0.26-0.90], respectively), and for community activities among women (0.19 [0.04-0.79] and 0.27 [0.09-0.77], respectively). Relaxation for the promotion of health should include both passive relaxation (rest) and active relaxation (recreation). In addition, ensuring sufficient sleep duration is important for passive relaxation, and engaging in outings/walking for men and community activities for women are important for active relaxation

Гомосексуальный субъект в пространстве публичного: нарративное измерение камин-аута

<div><p>Background</p><p>Although <i>Helicobacter pylori</i> (<i>H</i>. <i>pylori</i>) infection is closely associated with the development of peptic ulcer, its involvement in pathophysiology in the lower intestinal tract and gastrointestinal (GI) motility remains unclear. Glucagon-like peptide-1 (GLP-1) is a gut hormone produced in the lower intestinal tract and involved in GI motility. Here, we investigated the effect of <i>H</i>. <i>pylori</i> infection on the link between GLP-1 expression and motility of the GI tract.</p><p>Methods</p><p>C57BL/6 mice were inoculated with a <i>H</i>. <i>pylori</i> strain. Twelve weeks later, the <i>H</i>. <i>pylori</i>-infected mice underwent <i>H</i>. <i>pylori</i> eradication treatment. GI tissues were obtained from the mice at various time intervals, and evaluated for the severity of gastric inflammatory cell infiltration and immunohistochemical expression of GLP-1 and PAX6 in the colonic mucosa. Gastrointestinal transit time (GITT) was measured by administration of carmine-red solution.</p><p>Results</p><p>GLP-1 was expressed in the endocrine cells of the colonic mucosa, and PAX6 immunoreactivity was co-localized in such cells. The numbers of GLP-1- and PAX6-positive cells in the colon were significantly increased at 12 weeks after <i>H</i>. <i>pylori</i> infection and showed a positive correlation with each other. The GITT was significantly longer in <i>H</i>. <i>pylori</i>-infected mice than in non-infected controls and showed a positive correlation with GLP-1 expression. When <i>H</i>. <i>pylori</i>-infected mice underwent <i>H</i>. <i>pylori</i> eradication, GITT and PAX6/GLP-1 expression did not differ significantly from those in untreated <i>H</i>. <i>pylori</i>-infected mice.</p><p>Conclusions</p><p><i>H</i>. <i>pylori</i> infection may impair GI motility by enhancing the colonic GLP-1/PAX6 expression.</p></div

New CTI Correction Method for the Spaced-Row Charge Injection of the Suzaku X-Ray Imaging Spectrometer

The charge transfer inefficiency (CTI) of the X-ray CCDs on board the Suzaku satellite (X-ray Imaging Spectrometers; XIS) has increased since the launch due to radiation damage, and the energy resolution has been degraded. To improve the CTI, we have applied a spaced-row charge injection (SCI) technique to the XIS in orbit; by injecting charges into CCD rows periodically, the CTI is actively decreased. The CTI in the SCI mode depends on the distance between a signal charge and a preceding injected row, and the pulse height shows periodic positional variations. Using in-flight data of onboard calibration sources and of the strong iron line from the Perseus cluster of galaxies, we studied the variation in detail. We developed a new method to correct the variation. By applying the new method, the energy resolution (FWHM) at 5.9 keV at March 2008 is ~155 eV for the front-illuminated CCDs and ~175 eV for the back-illuminated CCD.Comment: 7 pages, 14 figure