Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island...Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island in Zhanjiang, China. The primary cultural and luminescent conditions of luminous bacterium D2 which was identified as Vibrio sp. were determined in liquid culture. The results showed that pH 7.0, 35 ℃, with 2.0 % NaCI, were the best growth conditions, and pH5 - 6, 20℃, OD600 0.08, with 3.0 % NaCI, were the optimal luminescent conditions.展开更多
Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have si...Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have similar influence upon muscular endurance. Therefore this study compared the number of weighted knee extension lifts that could be done after spending 1 h in either dim or bright light. Methods： Participants （5 women, 11 men, college students 19--26 years） performed knee extension lifts to exhaustion with a load approximating 40% of their body weight. The lifts to exhaustion were measured immediately following 1 h of exposure to each of the following three con- ditions： dark （DL）, room light （RL）, and room light plus 5 mg melatonin （RLM）. A minimum of 48 h separated each condition, and all par- ticipants started the exposures in a rested fed condition. Results： Average （±SD） number of knee extension lifts for RL （62.0 ± 22.0） was significantly （p 〈 0.05） greater than DL （51.4 ± 14.7） and RLM （57.8 ± 22.9）. The number of RLM knee extension lifts was not significantly different from DL. Exposure to 1 h of dim light immediately prior to activity can result in a reduction in thigh muscle endurance. The decline in performance to short-term dim light exposure was similar to that found following longer-term exposure. Conclusion： It appears that light intensity can influence muscle endurance, however, at this time this effect cannot be directly related to endogenous melatonin production.展开更多
文摘Study of marine noctilucence in marine is important to fishery, environmental monitoring and military affairs. A luminous bacterial strain D2 was isolated from the marine sediment samples collected near Donghai Island in Zhanjiang, China. The primary cultural and luminescent conditions of luminous bacterium D2 which was identified as Vibrio sp. were determined in liquid culture. The results showed that pH 7.0, 35 ℃, with 2.0 % NaCI, were the best growth conditions, and pH5 - 6, 20℃, OD600 0.08, with 3.0 % NaCI, were the optimal luminescent conditions.
文摘Background： Since it has been shown that spending 18 h under dim light conditions can result in reduced handgrip endurance, it was questioned whether or not a shorter exposure to dim light （i.e., 1 h） would have similar influence upon muscular endurance. Therefore this study compared the number of weighted knee extension lifts that could be done after spending 1 h in either dim or bright light. Methods： Participants （5 women, 11 men, college students 19--26 years） performed knee extension lifts to exhaustion with a load approximating 40% of their body weight. The lifts to exhaustion were measured immediately following 1 h of exposure to each of the following three con- ditions： dark （DL）, room light （RL）, and room light plus 5 mg melatonin （RLM）. A minimum of 48 h separated each condition, and all par- ticipants started the exposures in a rested fed condition. Results： Average （±SD） number of knee extension lifts for RL （62.0 ± 22.0） was significantly （p 〈 0.05） greater than DL （51.4 ± 14.7） and RLM （57.8 ± 22.9）. The number of RLM knee extension lifts was not significantly different from DL. Exposure to 1 h of dim light immediately prior to activity can result in a reduction in thigh muscle endurance. The decline in performance to short-term dim light exposure was similar to that found following longer-term exposure. Conclusion： It appears that light intensity can influence muscle endurance, however, at this time this effect cannot be directly related to endogenous melatonin production.
