N-n-ヘキシル-マレイミド (I), N-シクロヘキシル-マレイミド (II), N-ベンジル-マレイミド (III) の単独重合, 共重合をアゾビスイソブチロニトリル (IV) を開始剤としてテトラヒドロフラン中, 60℃で行った. 単独重合の初速度 (R_p) はR_p=k [I]

2.5

[IV]

0.80

, R_p=>k [II] ^2.8 [IV]

0.80

, R_p=>k [III] ^2.7 [IV] ^0.54となった. kは速度定数である. 全重合の活性化エネルギー (

E

), 頻度係数 (A) は

E

=

22

.8kcal/mol (I),

22

.2kcal/mol (II), 24.

1

kcal/mol (III), A=

9

.

5

×10¹¹ (I), 6.4×10¹¹ (II), 6.6×10¹² (III) となった. またN-置換マレイミドとメタクリル酸メチル (V) との共重合におけるモノマー反応性比

r₁

, r₂およびQ,

e

値を次のように決定した. I (

M₁

) -V (M₂) 系で

r₁

=0.17, r₂=2.02,

Q₁

=0.56,

e₁

=

1

.43, II (

M₁

) -V (M₂) 系で

r₁

=0.13, r₂=2.29,

Q₁

=0.50,

e₁

=

1

.50, III (

M₁

) -V (M₂) 系で

r₁

=0.14, r₂=

1

.54,

Q₁

=0.79,

e₁

=

1

.63となった.

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Corrosion and inhibition tests were conducted on Oil Country Tubular Goods (OCTGs) in HCl and HCl/HF stimulation acid solutions at 65°C.
Commercial inhibitors effectively inhibited L- and 13Cr steels. Cr duplex steel, however, was not inhibited satisfactorily, especially at low HCl/HF concentrations. The form of corrosion of Cr was selective attack. At low HCl/HF concentrations, corrosion product was formed on Cr surfaces and inhibitors were considered to be interfered by this corrosion product.
To inhibit Cr, and to mitigate selective attack, high dosage of inhibitor was required. Another way of corrosion control was attained by the increase in HCl concentration. The increase in HCl concentration made the corrosion reaction more active and reduced the tendency to form the corrosion product, and resulted in the activation of inhibitors for Cr in stimulation acid solutions.

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Purpose: The purpose of this study was to determine if the optical properties of zirconia and glass–ceramic (

.max) were affected by low-temperature degradation (aging).

Methods: Experiment samples were fabricated with seven zirconia brands (n=10): Zenostar, Zirlux, Katana, Bruxzir, DD-BioZX², DD-cubeX², NexxZr; and

.max were used as a control. This resulted in a total of samples in the experiment. The L*, a* and * were measured for each sample, and then the optical properties including translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) were calculated. The samples were aged (20, 40, 60, , 100h), and the optical properties were calculated after each interval.

Results: Most zirconia brands had lower L*, higher a*, higher

* with increased aging, which visually corresponds to darker, redder, and more yellow. Aging also increased CR, lowered TP, and lowered OP. .max was also affected by aging but still had the highest TP (23.±2.8), L* (81.7±3.4), and lowest CR (0.41±0.05) compared to any zirconia. The Zenostar had the closest TP (24.±0.4), and L* (90.2±0.) values to .max before aging. However, after 100h of aging, the DD-cubeX² was least effected and had the highest TP (.2±0.6) and lowest CR (0.43±0.01) compared with other zirconia samples and highest OP (11.3±0.2) of all ceramic samples.

Conclusions: The optical properties of zirconia and

.max materials were affected by aging with the effects increasing with time. The magnitude of change was affected by seven brands of dental zirconia.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–

,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-. Sixteen phosphate buffered saline (PBS), 8 boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3- cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-7,-diene-3β,,6β-triol (). induced ALP activities of MC3T3- cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3- cells by , ergosterol (2), ergocalciferol (3), cholesta-3β,,6β-triol (4), 7-dehydrocholesterol () and cholecalciferol (6) were tested. The enzyme activities of MC3T3- cells were increased 3.0-fold by 10 μM and 2.4-fold by 10 μM 4. However, 2, 3, and 6 did not induce MC3T3- cell ALP activity at 0.—10 μM. These results suggested that the OH groups at C- and/or C-6 of and 4 played an important role in their differentiation-inducing activities on MC3T3- cells. Furthermore, suppressed induction of MC3T3- cell apoptosis by serum starvation.

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A total of 176

E

. coli isolates were retrieved from 203 diarrheic fecal samples collected from Korean cattle on 117 different farms. The most frequently observed resistance in

E

. coli isolates was to tetracycline (.6%), followed by streptomycin (.7%) and ampicillin (64.8%). Resistance to cefazolin, cefoperazone, cefepime and amikacin was very low. Of the 176

E

. coli strains, forty (.7%) isolates from 30 farms showed resistance to fluoroquinolones (FQ). All the FQ-resistant strains possessed double mutations at codons 83 and 87 in the gyrA gene, and a single mutation mostly at codon in the parC gene, except in one isolate. The pulsed-field gel electrophoresis profiles of the FQ-resistant

E

. coli isolates were heterogeneous, but two or three isolates that showed an identical pattern originated from the same or different farms. This study demonstrates that FQ resistance is frequently observed in

E

. coli from diarrheic cattle and that mutations in the quinolone resistance-determining region are the same as those seen in

E

. coli originating from other animal species and humans. The FQ resistance in diarrheic cattle might have been mostly acquired independently, although the possibility of transmission of FQ-resistant

E

. coli within a farm or between farms is plausible.

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Emericella striata -NE- is a fungus (Ascomycetes) isolated from cumin collected in Nepal. From its mycelial extract, novel macrocyclic epipolythiodioxopiperazines, emestrin () and emestrin (2), were isolated along with shamixanthone, emericellin, sterigmatocystin, and paxilline. The structures of and 2 were determined on the basis of the spectroscopic investi-gation of their derivatives and X-ray crystallography of emestrin methanol solvate. Emestrin () has strong antifungal activity, especially against Microsporum spp. and Trichophyton spp. Three compounds relating to , dethiosecoemestrin (3), aurantioemestrin (4) and violaceic acid (), were isolated from the culture filtrate, and their structures were elucidated by the spectroscopic investigation. Isolation of dethiosecoemestrin (3) and aurantioemestrin (4) along with emestrin () and emestrin (2) from the same fungus suggested the biodegradation of epidithiodioxopiperazines into trioxopiperazines. Emestrin () was also isolated from several species belonging to the genus Emericella; . foveolata, . quadilineata, . acristata, and . parvathecia.

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Six full-length cDNAs encoding pig cytochrome P450 (CYP) enzymes, CYPA, CYP2A19, CYP2, CYP2C33v4, CYP2C49, and CYP2, were isolated and sequenced. The cDNA sequences of pig CYPA, CYP2A19, CYP2, CYP2C49, and CYP2 showed high similarity to human (85.4%), CYP2A13 (.6%), (81.%), CYP2C18 (85.3%), and (82.%), respectively, and pig CYP2C33v4 cDNA showed high similarity to rat CYP2C23 (79.2%). Reverse transcription-polymerase chain reaction (RT-PCR) assays revealed hepatic gene expression of all these pig CYP enzymes: the order of expression was CYP2C33v4 and > CYP2C49 > and CYP2A19 > . In the kidney, the CYP2C33v4 gene was expressed at the same level as in the liver, but the , CYP2A19, and genes were expressed at lower levels than in the liver. Little renal gene expression of CYP2C49 and CYP2 was observed. We revealed for the first time the full-length cDNA sequences encoding pig CYPA and five CYP enzymes belonging to the CYP2 gene family, thus making it possible to examine the gene expression levels of these CYP enzymes in pig tissues by RT-PCR.

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広域PC, ticarcillin (TIPC) とβ-lactamase不活化剤, clavulanic acid (CVA) を15:に配合したBRL 28500のS. aureus, MRSA, S. epidermidis,β-Streptococci, S. pneumoniae,

E

. coli (R⁺), K. pneumoniae, P. mirabilis, P. vulgaris, M. morganii, C. freundii,

E

. cloacae, S. marcescens, H. in fluenzae, P. aeruginosa, X. maltophilia, A. calcoaceticus, 及び

B

. fragilisの～54臨床分離株に対するは, それぞれ12., 50, 25, .56, 0.78, 50, 50, 0.78, 6.25, 12., 50,>100, 50, .56, 50,100, 25及び3.13μg/mlであった。さらにCVA2μg/ml存在下のTIPCのは上記の値より小さい場合が多かった。BRL 28500は

E

. coliのPBP3, A, 2, の順に結合親和性を示し, 殺菌力の高いことを伺わせた。S. aureusのPBP2と3及びP. vulglarisのPBP, 3A, 3にも強い結合親和性がみられた。BRL 28500は, TIPC耐性

E

. coliにも低濃度で補体との協力的殺菌作用を示し, そのsub MIC存在下でマウス培養Mφは,

E

. coliの細胞をよく食菌消化した。

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M-2 mixing ratio δ, and the 0-2 mixing ratio μ_k are obtained for 818.7 keV +→2₁⁺ transition to be δ=−+0.26, and μ_k≤6.×10⁻⁴ respectively. The 2 branching ratio (2; +→0_g⁺): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be 0.0158:.0:.86.

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In the first part of the present work the interaction of glycophorin with dimyristoylphosphatidylcholine (DMPC) is studied by freeze fracture electron microscopy, densitometry, calorimetry, and 90° static light scattering. An exothermic lipid/protein interaction energy of W_P=190 kJ•mol-

1

was found by application of the well known Van Laar relation for the displacement of the freezing point and the Gibbs-Duhem relationship. Secondly, the effects of Ca²⁺ on the lipid/protein interaction were studied. Following Ca²⁺ addition a remarkable decoupling of the interaction of the glycophorin head group with the bilayer surface was revealed by densitometry and gold-labeling electron microscopy. It is estimated that about

80

% of lipid once disturbed by the adsorption of glycophorin head groups is decoupled after addition of Ca²⁺. Thirdly, the selective interaction of glycophorin with binary lipid mixtures was studied, including the mixtures of DMPC with dimyristoylphosphatidylserine (DMPS) and dilauroylphosphatidylcholine (DLPC), and the mixture of dipalmitoylphosphatidylcholine (DPPC) with DLPC.

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A study has been conducted to develop the composite sheets made by superplastic rolling/joining technique of steel-superplastic alloys which could be used for the damping material at high temperature. The superplastic alloys used were Zn-%Al alloy, Al-6%Cu-0.%Zr alloy and Al-12.%Mg₂Si alloy and the composite sheets consisted of the three layers of steel and superplastic alloy (. g. steel-s. p. alloy-steel, s. p. alloy-steel-s. p. alloy). In case of Zn-%Al alloy, the volume percentage of the alloy was changed at five steps of 0, 25, 50, 75 and 100%. The specimens were rolled at 4 or passes at 200°C and the final reduction became %. The laminar and granular structures could be obtained by heat treatments after rolling. In case of the other alloys, the volume percentage of the alloys was 50%. The specimens were rolled at 300°C and the final reduction became %. The results obtained were as follows;
() The damping capacity of the steel-Zn-%Al alloy composite sheet could be obtained several times values of the steel in room temperature. The damping capacity increased with increasing temperature. Above the temperature of 200°C, the damping capacity exceeded 0..
(2) In the composite sheets of steel-Al superplastic alloys, good formability could be obtained by heat treatment.

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The microstructure of explosively compacted Nd-Fe- alloys has been investigated by means of transmission electron microscopy and X-ray diffraction. It is shown that there are three kinds of phases, i.

e

. the matrix phase , O-rich phases and Nd-rich phases in explosively compacted Nd-Fe- magnets. The matrix phase is tetragonal, with lattice parameters of a=0. nm and c=. nm. The O-rich phase was present at the two-grain boundary and three-grain junctions, with the fcc structure, and the lattice parameter is a=0.559 nm. The O-rich phase belongs to the compound Nd-Fe-O, and the contents of O, Nd and Fe are 45–60 at%, 20–40 at% and 10–21 at%, respectively. It is also shown that a large number of block-shaped Nd-rich phases are in a two-grain boundary or three-grain junctions or phase, with the hcp structure and the lattice parameters of a=0.395 nm and c=0.628 nm. The Nd-rich phases belong to compound Nd-O, and the contents of Nd and O are –85 at% and 10–15 at%, respectively. Also a few dislocations in the boundary phase have been observed.

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The semen quality of dogs (4 to 7 years old) with benign prostatic hyperplasia (BPH) was examined at the hospital of our university, and 4 of the BPH dogs were diagnosed as azoospermic. The mean peripheral plasma estradiol-17β () level (17.3 pg/ml) of the 18 BPH dogs with spermatogenic function was higher than that of normal male dogs and their mean T level (.7 ng/ml) was lower. The mean level (27.3 pg/ml) of the 4 BPH dogs with azoospermia was significantly higher than the value in the BPH dogs with spermatogenic function (P<0.01), and the mean T level (. ng/ml) was significantly lower (P<0.05). Five normal male dogs were given 10 intramuscular injections of estradiol benzoate () μg/kg, at 3-day intervals to investigate the relationship between high plasma levels and the cause of the BPH and azoospermia. Their testes and prostates were measured and biopsied both before and 30 days after the start of injections. At 30 days after the start of the injections, the mean peripheral plasma T levels had decreased by half, and the mean testicular volume had decreased to % of original volume. The numbers of spermatocytes, spermatids, and spermatozoa in the seminiferous tubules of all of the dogs were significantly lower (P<0.05, 0.01). In addition, the mean prostatic volume increased to 130%, the mean height of the glandular epithelium decreased, and the glandular lumen became increased in diameter. These findings indicate that both BPH and serious spermatogenic dysfunction may be simultaneously induced by protracted high plasma levels in dogs.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the Tb¹⁵² activity. The L-subshell electron lines of the 586.7 keV +→2₁⁺ transition are separated by the ion-free beta-ray spectrometer. The M-2 mixing ratio, δ², and the dimensionless ratio X of 0-2 mixing of the 586.7 keV transition are obtained to be δ²≤0.16 and 0.034≤X≤0.038, respectively. The 2 branching ratio (2; +→0_g⁺): (2; +→2₁⁺): (2; +→0₁⁺) is determined to be 0.023 : .0 : .6.

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