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Hot Conditions (hot + condition)
Selected AbstractsExclusively breastfed, low birthweight term infants do not need supplemental waterACTA PAEDIATRICA, Issue 5 2000RJ Cohen Breast milk intake, urine volume and urine-specific gravity (USG) of exclusively breastfed, low birthweight (LBW) term male infants in Honduras were measured during 8-h periods at 2 (n= 59) and 8 (n = 68) wk of age. Ambient temperature was 22,36°C and relative humidity was 37,86%. Maximum USG ranged from 1.001 to 1.012, all within normal limits. Conclusions: We conclude that supplemental water is not required for exclusively breastfed, LBW term infants, even in hot conditions. [source] Changing Fire Management in the Pastoral Lands of Cape York Peninsula of northeast Australia, 1623 to 1996GEOGRAPHICAL RESEARCH, Issue 1 2000G.M. Crowley Accounts of European explorers between 1623 and 1880 indicate that fires were lit by Aboriginal people on Cape York Peninsula in northeast Australia throughout the dry season (May,October). Diaries kept by three generations of pastoralists in the Musgrave area (1913,1952, 1953,1974 and 1976,1992) show that burning activities were largely confined to a two to six week period between May and early August. The timing of burning depended on the amount and date of cessation of wet season rainfall. More rarely, ,storm-burning', burning under hot conditions within a few days of the first heavy rains of the wet season, was undertaken. Long-term pastoralists felt a responsibility to use fire wisely and had a detailed knowledge of the role of fire in land management. Their decisions to burn were based on the extent of grass curing, and soil and weather conditions, all of which affected the extent of each burn. They used early dry season fires mainly to maintain forage and control cattle movements. Storm-burns were reputed to control woody weeds, but were used infrequently because of difficulty in controlling their spread and uncertainty as to when the next rains would stimulate new grass growth. [source] Photoperiodic and temperature control of diapause induction and colour change in the southern green stink bug Nezara viridulaPHYSIOLOGICAL ENTOMOLOGY, Issue 2 2003Dmitry L. Musolin Abstract. The effect of photoperiod and temperature on the duration of the nymphal period, diapause induction and colour change in adults of Nezara viridula (L.) (Heteroptera: Pentatomidae) from Japan was studied in the laboratory. At 20 °C, the developmental period for nymphs was significantly shorter under LD 10 : 14 h (short day) and LD 16 : 8 h (long day) than under intermediate photoperiods, whereas at 25 °C it was slightly shorter under intermediate than short- and long-day conditions. It is assumed that photoperiod-mediated acceleration of nymphal growth takes place in autumn when day-length is short and it is unlikely that nymphal development is affected by day-length under summer long-day and hot conditions. Nezara viridula has an adult diapause controlled by a long-day photoperiodic response. At 20 °C and 25 °C in both sexes, photoperiodic responses were similar and had thresholds close to 12.5 h, thus suggesting that the response is thermostable within this range of temperatures and day-length plays a leading role in diapause induction. Precopulation and preoviposition periods were significantly longer under near-critical regimes than under long-day ones. Short-day and near-critical photoperiods induced a gradual change of adult colour from green to brown/russet. The rate of colour change was significantly higher under LD 10 : 14 h than under LD 13 : 11 h, suggesting that the colour change is strongly associated with diapause induction. The incidences of diapause or dark colour did not vary among genetically determined colour morphs, indicating that these morphs have a similar tendency to enter diapause and change colour in response to short-day conditions. [source] Effect of high environmental temperatures on ascorbic acid, sulfhydryl residue and oxidized lipid concentrations in plasma of dairy cowsANIMAL SCIENCE JOURNAL, Issue 3 2007Masahito TANAKA ABSTRACT Information on oxidative stress under hot conditions from the levels of cells to organs and the whole body has accumulated in the last decades. Although a hot climate decreased dairy performance, changes of oxidative stress markers under hot conditions have remained obscure. Therefore, the effect of high environmental temperature on ascorbic acid, sulfhydryl (SH) residue and oxidized lipids concentrations in plasma from a total of 128 dairy cows was investigated. The monthly average maximum day temperature varied from 9.2°C in January to 32°C in August of 2004 in this institute. High ambient temperatures increased the rectal temperature of dairy cows up to 39.3°C in August. One of the reducing equivalents in plasma, SH residue concentration, decreased in July compared with December (P < 0.05). Another antiradical molecule, ascorbic acid concentration in plasma, also decreased in July (P < 0.01). The oxidative stress index, thiobarbituric acid reactive substance (TBARS), which was produced from the oxidation of polyunsaturated fatty acids under oxidative conditions, increased in summer (P < 0.05). A significant positive relationship of SH residue and ascorbic acid concentrations in the hot season was observed (P < 0.01). A negative correlation between rectal temperatures and ascorbic acid concentrations in the hot season was obtained (P < 0.01). However, TBARS concentration varied independently of the SH residue and ascorbic acid concentration. These results suggest that the response of oxidative stress markers of SH residue, ascorbic acid and TBARS concentration to oxidative stress under hot conditions were not shown to be the same, and that oxidative stress in dairy cows in the hot season increased. [source] | ||||||||||