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High road-surface temperature due to heat waves can lead to dangerous driving conditions such as tire blowouts and deformation induced by thermal stress on the roads. In this study, a Mobile Observation Vehicle dataset, with high spatial and temporal resolutions for the heat-wave episode that occurred on 16–17 August 2018, is used to understand environmental characteristics on urban road-surface and air temperatures in Seoul. This study demonstrates that the magnitude of urban road-surface temperature is dependent on the differences in incoming solar radiation due to screening of high-rise buildings in the Gangnam area, and is associated with the topographical features in the Gangbuk area. The road-surface temperature in the section of darker-colored asphalts was higher than that of lighter-colored asphalts, with a mean difference of 6.8°C, and both surface and air temperatures on the iron plate were highest, with means of 51.7°C and 35.1°C, respectively. In addition, during the water-sprinkling period, road-surface temperature was cooled by about 8.7°C (19%) compared with that in the period without water-sprinkling, but there was no significant change in air temperature. The current results could be practically used to improve road-surface temperature prediction models for civil engineers or road managers.

This study examined factors affecting intention to enroll in an organ donor registry and intention to talk to family about organ donation. Participants indicated their views about maintaining body integrity as an individual right and donating organs as a social responsibility. Results showed that the influence of social responsibility on intention to enroll was stronger for white Americans than for Asian Americans. Individual right was negatively associated with intention to enroll among Asian Americans, but not among white Americans. Social responsibility was significant for intention to talk among both white Americans and Asian Americans, but individual right was not significant.

An investigation of folate compounds in the kidney, red blood cells, and urine of rats was made by tracing the radioactivity 24 hr after the injection of 20μCi [ 3 H]folic acid. Column chromatography of tissue folates with standard marker compounds on Sephadex G-15 and G-25, and DEAE-cellulose columns shows the following results: (1) 75%-80% of kidney folates consists of reduced derivatives of pteroylpentaglutamate; (2) ca. 95% of total folates in red blood cells are 5-methyl derivatives of reduced pteroylpolyglutamates, mainly as pentaglutamate (ca. 60%) and hexaglutamate (ca. 35%); (3) more than 90% of urine folates are identified as derivatives of pteroylmonoglutamate.

[3H]Methotrexate was metabolized mainly to 4-amino-4-deoxy-10-methylpteroic acid in resting cells of Lactobacillus casei and a small amount of methotrexate remained inside the cells after 24 hours of incubation. Preincubation of L. casei with methotrexate inhibited the incorporation of [3H]folic acid completely and l-5-formyl-[3H]tetrahydrofolic acid partially into pteroyloctaglutamate and increased the amount of pteroyltetraglutamate and lower polyglutamates. In rats, methotrexate was metabolized partially to lower methotrexate polyglutamates; however, its uptake was much lower than folic acid and no pentaglutamate of methotrexate was found. Pretreatment of rats with 100 µg of methotrexate daily for 5 days decreased the uptake of [3H]folic acid into liver considerably (∼20 to ∼8%) and the radioactivity in liver was mainly reduced derivatives of pteroylpentaglutamate. With treatment with 300 µg of methotrexate per day for 6 days, however, not only the uptake of [3H]folic acid decreased to ∼4%, but also pteroylpentaglutamate comprised only ∼50% of total radioactivity in liver and the rest was lower polyglutamate and unmetabolized monoglutamate. Column chromatography with Sephadex G-25 and DEAE-cellulose provides a good method for the identification of methotrexate-related compounds.

Summary. The mechanisms of the low availability of endogenous folates in orange juice and the inhibitory effects on the availability of pteroylheptaglutamate (PteGlu7) caused by orange juice supplements were investigated in man by the use of simulated orange juice (containing the principal components: citric acid, malic acid, etc.) with several different pHs. The endogenous folates in orange juice were identified as mainly 5-methyl reduced derivatives of pteroylpolyglutamates (40–45% pentaglutamate, 10–15% tetraglutamate, 30–40% monoglutamate, and the rest were tri- and diglutamates). The availability of PteGlu7 is decreased to 54% by supplementation with 600 g concentrated orange juice (pH 3.7) and to 39% and 66% by the supplement of 24 g and 12 g citric acid (pH 3.7), respectively. Neutralization of 12 g citric acid to pH 6.4 largely reverses the inhibitory effect. On the other hand, the availability of pteroylmonoglutamate (PteGlu) is not influenced by a supplement of orange juice or citric acid. The results suggest that the low availability of PteGlu7 is due to the inhibition of intestinal conjugase caused by the low pH. These observations suggest that pH of foodstuffs may be an important factor in the absorption of polyglutamate forms of folate.

The separation of folate compounds has been achieved by gel chromatography and the effect of buffer concentration on the elution pattern of folate derivatives was investigated by Sephadex G-15 and G-25 column chromatography. Highly conjugated polyglutamates appear in the effluent considerably sooner when eluted with water than would be expected from their molecular weights. Monoglutamates, except 10-formyltetrahydropteroylglutamic acid, are retarded on G-15 and G-25 in phosphate buffer (pH 7.0) solvent system; the situation becomes more apparent as the buffer concentration is increased. Chromatography on Sephadex G-25 with 0.1 m phosphate buffer, pH 7.0, containing 0.2 m 2-mercaptoethanol gives a satisfactory separation of pteroylpolyglutamates containing 2 to 7 glutamic acid residues.