33 research outputs found
Communicative success in spatial dialogue: The impact of functional features and dialogue strategies
This paper addresses the impact of dialogue strategies and functional features of spatial arrangements on communicative success. To examine the sharing of cognition between two minds in order to achieve a joint goal, we collected a corpus of 24 extended German-language dialogues in a referential communication task that involved furnishing a dolls’ house. Results show how successful communication, as evidenced by correct placement of furniture items, is affected by a) functionality of the furniture arrangement, b) previous task experience, and c) dialogue features such as description length and orientation information. To enhance research in this area, our 'Dolldialogue' corpus is now available as a free resource on www.dolldialogue.spac
Use of modified cages attached to growing calves to measure the effect of stable flies on dry matter intake and digestibility, and defensive movements
The effects of stable flies on growing calves were examined using fly cages attached to the animals. Dry matter intake, DM digestibility (DMD), and behavioral responses of calves were monitored. Nine Holstein calves were exposed to 3 levels of stable flies (0, 10, 100 flies/animal) 3 times daily for 30 min. The study consisted of a 4-period crossover design; each period included 5-d adaptation, 7-d exposure, and 5-d postexposure. Calves were weighed at the beginning and end of each period. Feed consumption was continuously recorded. Fecal samples taken during and after exposure were used to determine DMD. Three calves were monitored for activity and defensive behavior during exposure. Caged stable flies successfully fed on the calves and invoked defensive behaviors similar to those observed in field studies. Defensive behaviors were proportionate to exposure level, and calves became more proficient at interfering with fly feeding over time. Stable fly exposure increased DMI relative to calf weight and decreased ADG/DMI. Calves initially exposed to 100 flies exhibited more defensive behaviors and lower relative DMI and ADG across all exposure levels relative to calves initially exposed to 10 flies. Stable fly exposure did not affect DMD, number of meals, time eating, or amount eaten per meal. Host defensive behavior, not reduced DMI or DMD, appears to be reducing ADG of calves exposed to stable flies. Results indicate that cages placed on calves may be used to study the effects of stable flies, but host exposure history and behavioral variables must be considered
Critical Dynamics of a Two-dimensional Superfluid near a Non-Thermal Fixed Point
Critical dynamics of an ultracold Bose gas far from equilibrium is studied in
two spatial dimensions. Superfluid turbulence is created by quenching the
equilibrium state close to zero temperature. Instead of immediately
re-thermalizing, the system approaches a meta-stable transient state,
characterized as a non-thermal fixed point. A focus is set on the vortex
density and vortex-antivortex correlations which characterize the evolution
towards the non-thermal fixed point and the departure to final
(quasi-)condensation. Two distinct power-law regimes in the vortex-density
decay are found and discussed in terms of a vortex binding-unbinding transition
and a kinetic description of vortex scattering. A possible relation to decaying
turbulence in classical fluids is pointed out. By comparing the results to
equilibrium studies of a two-dimensional Bose gas, an intuitive understanding
of the location of the non-thermal fixed point in a reduced phase space is
developed.Comment: 11 pages, 13 figures; PRA versio
5-fluorocitosina e anfotericina-B no tratamento da criptococose do sistema nervoso central
Chapter 18- Chick Survival of Greater Prairie-Chickens
Chick survival during the first three weeks of life is a critical stage in the demography of Greater Prairie-Chickens (Tympanuchus cupido), but little information is available. Biologists often estimate brood success using periodic flushes of radio-marked females, but it is impossible to determine mortality factors if chicks are not radio-marked. We used sutures to attach 0.5-g transmitters to 1- to 2-day-old chicks in Johnson County, Nebraska, during 2008. Our objectives were to (1) assess causes of mortality of 0- to 21-day-old chicks, (2) estimate daily survival probability for 0- to 21-day-old chicks, and (3) evaluate the effect of applying transmitters with suture attachment to chicks. We monitored a total of 221 prairie chicken chicks from 20 broods. We radio-marked 27 chicks from 10 broods of radio-marked females (one to five chicks per brood). The chicks were located twice per day to ensure that they were within a 10-m radius of the female. Our limited sample showed a weak effect of radio-marking on the survival of prairie chicken chicks (β= –0.54; SE= 0.33). Forty-two (19%; 95% CI: ±5%) of the 221 chicks in our sample survived to day 21, confirming low rates of productivity observed in hunter wing surveys and brood flushes of radio-marked females in a concurrent study. All radio-marked chicks in our sample died (13% exposure; 87% predators) before 21 days of age. Survival of chicks increased with age, and survival decreased during periods with high precipitation. Daily and 21-day survival rate estimates for all chicks in our sample were 0.926 (95% CI: 0.915–0.937) and 0.193 (95% CI; 0.155–0.255), respectively. Predation appeared to be the most critical factor for chick survival, so management of landscapes to reduce risk from predators may have a positive effect on Greater Prairie-Chicken populations