50 research outputs found
Daily torpor: When heart and brain go cold - Nonlinear cardiac dynamics in the seasonal heterothermic Djungarian hamster
Djungarian hamsters (Phodopus sungorus) acclimated to short photoperiod display episodes of spontaneous daily torpor with metabolic rate depressed by ∼70%, body temperature (
Winter activity of a population of greater horseshoe bats (Rhinolophus ferrumequinum)
Activity patterns of a greater horseshoe bats Rhinolophus ferrumequinum were investigated at caves in Cheddar (south-west England) during the hibernation season. An ultrasound detector and datalogger were used to monitor and record the number of echolocation calls in a single cave. Activity of R. ferrumequinum remained largely nocturnal throughout winter, and the mean time of activity over 24 hours was 88 to 369 minutes (1.47 to 6.15 hours) after sunset. There was an increase in diurnal activity from late May to early June, probably because bats remained active after foraging at dawn towards the end of the hibernation season. Visits to the cave did not increase bat activity. Cave air temperature reflected external climatic temperature, although there was variation in cave temperature and its range within and across caves. Individual R. ferrumequinum are usually dispersed in caves in regions where temperature fluctuations correlate with climatic variations in temperature. There was a positive correlation between the number of daily bat passes monitored by the bat detector and datalogger (= daily activity) and cave temperature. Nocturnal activity may sometimes be associated with winter feeding. Neither date nor barometric pressure had a significant effect on daily activity. Activity patterns largely reflected the findings from individual R. ferrumequinum studied by telemetry (Park, 1998), in that bat activity increased with cave and climatic temperatures, and the temporal pattern of activity remained consistently nocturnal throughout winter, starting at dusk
Thermoregulation and heterothermy in some of the smaller flying foxes (Megachiroptera) of New Guinea
Body temperature, heterothermy, oxygen consumption, heart rate, and evaporative water loss were studied in four species of flying foxes (Megachiroptera), Dobsonia minor, Nyctimene major, Nyctimene albiventer , and Paranyctimene raptor , from the vicinity of Madang on the north coast of New Guinea.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47105/1/359_2004_Article_BF00297716.pd
An Overview of the Regional Experiments for Land-atmosphere Exchanges 2012 (REFLEX 2012) Campaign
Quantification of bio-geophysical variables of different surfaces is essential for understanding the earth system and for the development of earth system models for prediction of climate and environmental change. Understanding these variables remains problematic due to a lack of observational data at appropriate scales. Therefore this research campaign was carried out. A large scale of data was measured, for example satellite, air-borne, atmospheric, ground radiometric and flux tower data was collected
Doeltreffende risicocommunicatie
Dit rapport bevat een verslag van een onderzoek naar de doeltreffendheid en toekomstbestendigheid van de manier waarop de Nederlandse overheid over risico’s communiceert. In deze context houdt doeltreffendheid in dat de communicatiedoelen bereikt worden, dat de communicatie aansluit bij de informatiebehoefte van de burger, dat de beoogde doelen consistent zijn met relevant beleid, en dat zij op een adequate en efficiënte manier worden bereikt. Het onderzoek richt zich dus zowel op de reacties van burgers op de communicatie als op de processen bij de overheid