No description available.

Three brooding corals, Seriatopora hystrix, Stylophora pistillata, and Pocillopora damicornis in Nanwan Bay, southern Taiwan, revealed a diel rhythm of larval release. Planulation by S. hystrix and S. pistillata was highly synchronized with one peak of planula release occurring close to sunrise. Planulae of P. damicornis were released throughout the day with two peaks occurred in the early morning and at night. We maintain corals in laboratory with varied light-dark cycle and temperature to determine the mechanism of their release rhythm. S. hystrix did not release larvae under constant light and constant dark, thus the release of larvae in S. hystrix is not controlled by an endogenous rhythm. Peak of larval release occurs after 23hrs of light cue and under the dark. Temperature treatments, in 1¢J intervals from 23.5-28.5¢J, did not change the timing of larval release. We infer that the diel rhythm of larval release of S. hystrix controlled by sunrise. S. pistillata did not release larvae under constant light and constant dark. The larval release pattern of S. pistillata is similar to S. hystrix. Thus, we infer that sunrise may be the cues for the diel rhythm of larval release of S. pistillata. P. damicornis releases larvae under constant light and constant dark, and exhibit a rhythm of larval release with 37 h periodicity under constant dark. The regulation of its larval release is complex. These results suggest that the interspecific mechanism controlling diel rhythm of larval release may be different.

The seasonality, lunar and diurnal periodicity of planulation of five scleractinian corals, Seriatopora hystrix, Stylophora pistillata, Pocillopora damicornis, Euphyllia glabrescens and Tubastraea aurea, were compared. Corals were collected monthly and maintained in outdoor, flow-through systems to quantify the number of larvae released. Planulation of the five species occurred throughout the year. The long period of reproduction may be related to the warm mean seawater temperature in Nanwan Bay. S. pistillata released few larvae during late summer and early fall, suggesting the seasonality of reproduction. The pattern of lunar cycle can be classified into three strategies: (1) Planulation of S. hystrix and P. damicornis showed clear lunar periodicity and the peak of larval release shifted with different months. The peak of planulation occurred around the full moon in winter then shifted gradually to the first quarter moon phase in summer. The phase shift of larval release may be related to the seasonal variation of seawater temperature and the sudden temperature drops caused by upwelling. (2) Planulation of S. pistillata showed clear lunar periodicity and the peak of larval release occurred around the full moon. This may promote the larval dispersal. (3) E. glabrescens and T. aurea showed clearly lunar periodicity and the peak of larval release changed with different months. The peak of planulation shifted from full moon to new moon during winter and spring while it shifted from new moon to full moon during summer and fall. The pattern of diurnal cycle also can be classified into three strategies: (1) Planulation of S. hystrix and S. pistillata revealed a well-defined diurnal pattern with most planulae being released close to sunrise. (2) P. damicornis and E. glabrescens released larvae throughout the day, with two peaks occurring in the early morning and in the night. Corals of all three pocilloporids and E. glabrescens timed larvae release relative to the light-dark cycle suggesting that diurnal cycle determined when larvae were released. Larvae released in the dark may have lower risk of predation effect. Furthermore, the peak planulation occurred close to sunrise may be advantageous for some mature larvae to have light cues for quick settlement within the natal reef. (3) The azooxanthellate coral T. aurea released larvae throughout the day with no apparent cycle. These results suggest that zooxanthellae may play a role in regulating the diurnal cycle.

No description available.

The current study investigated the relation between academic rumination and achievement goal orientation using hierarchical regression. One hundred and ninety-six first year undergraduate students completed measures of depressive symptoms (BDI), achievement goal orientation (PALS) and rumination (MDRS). Analysis revealed that participants adopting performance-avoid goals were more likely to engage in brooding and reflective ruminative responses to stressful academic situations, while those reporting adopting mastery goal orientations were more likely to report lower brooding scores in stressful academic situations. Further analysis revealed that the relation between academic rumination and achievement goal orientation extended beyond a shared relationship with depressive symptoms. These findings are a first step in demonstrating a relationship between academic rumination and achievement goal orientations which may help to improve motivational intervention programs that assist students in adopting mastery goals as well as coping with stressful academic situations. / Graduate

During the first seven to ten days of life chicks are unable to maintain homeothermy, thus providing supplemental heat is critical to their livability and performance. Radiant heaters are the preferred method of providing heat during brooding because they provide a range of thermal comfort options for chicks. Infrared thermography is often used to assess the heat distribution created at the litter surface by radiant heaters. The resulting images provide a good qualitative assessment of heat distribution but do not provide any quantifiable metrics through which to compare the radiant output of heaters. Data acquisition systems were developed to measure the radiant flux emitted by six 11.72 kW radiant heaters and to determine radiant flux ranges preferred by broiler chicks during the first week of brooding. Results showed the radiant output was influenced by heater elevation above the litter and differed between manufacturers. 21 – 41% of the energy available the heaters was emitted to the litter as radiant heat. Chicks exhibited a decreasing preference for radiant flux with age. Maximum preferred radiant flux decreased from 387.0 W·m-2 at day 1 to 248.3 W·m-2 at day 8, while the minimum preferred radiant flux decreased from 61.2 W·m-2 at day 1 to 7.65 W·m-2 at day 8. Net usable area (NUA), or the total floor area within the range of radiant fluxes preferred by chicks, was calculated for each heater. Mean NUA by heater ranged from 45.34 (SE = 3.35 m2) to 21.75 (SE = 1.98 m2). Mean NUA significantly increased with heater mounting elevation (P < 0.0001). Results indicate that radiant heaters from different manufacturers with the same power output do not necessarily produce the same radiant distribution and that the maximum preferred radiant fluxes by chicks may not be realized at manufacturer specified heater mounting elevations.

Parental care in animals can be costly and is shared between both parents in many bird species. Not surprisingly, most studies of how parental care is shared between the sexes are in sexually dimorphic species, and much less in known about sexually monomorphic species where sex cannot be determined in the field. This has prevented a full understanding of parental care behaviors – which are intrinsically linked to fitness – in species such as the Red-headed Woodpecker (Melanerpes erythrocephalus) that is experiencing population declines throughout much of its range. In this study we assessed whether Redheaded Woodpecker brooding time, nestling provisioning rates, and nest cleaning rates vary as a function of parent sex, habitat type (savanna and closed canopy forest), brood size, nestling age, temperature and/or date. We recorded and analyzed 128 hours of high-quality video from 21 broods at Fort A.P. Hill, Virginia where this species is relatively abundant. We captured and color-banded Red-headed Woodpeckers, taking breast feather samples for genetic sexing, and determined brood size and chick age of nests using an extendable pole camera. Using generalized linear mixed models, we found the best predictor of nestling provisioning was an interaction between chick age and date; older chicks were fed more frequently in early summer (before 7 July) compared to late summer. The seasonal reduction in provisioning could be related to a reduction in resource availability, but whether or not provisioning in later nests affects nestling survival warrants further study. We found chick age and parent sex to be the best predictors in brooding models, with females brooding more when chicks are less than 10 days old and males being the only parent to enter the cavity after 10 days. Additionally, males almost exclusively remove fecal sacs from nests, highlighting an observational method to determine sex of breeding adults in the field. Such division of reproductive roles is similar to what is known for dimorphic woodpecker species and likely indicates energetic constraints due to the need for high parental investment from both sexes. Parental care is inextricably linked with habitat quality and home range size. Parents will travel to obtain the resources necessary to provision their young, and larger home ranges during the demanding nestling provisioning stage may indicate increased effort resulting from fewer available resources near the nest. We estimated home range sizes of 25 breeding adult Red-headed Woodpeckers using PinPoint GPS tags and 95% kernel density estimates (KDEs) with plug-in smoothing factors. We modeled the effects of habitat, sex, nest stage, date, and distance to nearest neighbor on home range estimates. Red-headed Woodpecker males have larger home ranges than females, and late summer home ranges are smaller than those measured before 7 July. More study is needed to determine if sex or date is a stronger factor on home range, given our naive sampling which resulted in more females sampled in late summer and observations that did not continue to the end of the breeding season (late August). Since we found date to be an influential factor to both provisioning rate and home range size, it is possible that seasonal resource changes are an important, unstudied factor related to nationwide declines of this species.

The thesis aim was to increase understanding of interpersonal antecedents and consequences of rumination, defined as ‘repetitive and passive thinking about one’s symptoms of depression and the possible causes and consequences of those symptoms’ (Nolen-Hoeksema, 2004, p.107). As a proof-of-principle study, rumination predicted diminished relationship satisfaction, three months later, in a sample of remitted depressed adults (N = 57). In the next study, rumination was associated with a maladaptive submissive interpersonal style and rejection sensitivity, controlling for depressive symptoms, other interpersonal styles and gender, in a different sample (N = 103 currently depressed, previously depressed and never depressed adults). Subsequent chapters incorporated a second assessment point of data from this same sample. Longitudinal analyses were undertaken to investigate; a) do rumination and depressogenic interpersonal factors predict future depression?; b) does rumination prospectively predict increased rejection sensitivity and submissive interpersonal behaviours, and, vice-versa, do these interpersonal factors predict increased rumination?; c) does rumination prospectively predict poor social adjustment and interpersonal stress? Consistent with previous findings, Time 1 rumination predicted increased depression six months later. Unexpectedly, the effect of rumination on future depression was mediated by its relationship with the submissive interpersonal style. Partially consistent with the stated predictions, Time 1 rejection sensitivity (but not the submissive interpersonal style) prospectively predicted increased rumination, but rumination did not predict rejection sensitivity or the submissive interpersonal style. As predicted, rumination prospectively predicted increased chronic interpersonal stress and poor social adjustment (but not acute interpersonal stress). In a final study, rumination was manipulated via an applied intervention (concreteness training, CT), within the context of a randomized controlled trial (N = 79 clinically depressed adults). Analyses compared the change in social adjustment and submissive interpersonal behaviour reported in the CT condition compared to a treatment as usual (TAU) condition. There was a significantly greater reduction in rumination in the CT compared to TAU condition, p < .05. Moreover, the reduction in submissive interpersonal behaviours was significantly greater in the CT compared to TAU condition, p < .05. The change in social adjustment was not greater in the CT compared to TAU condition. Thus, a psychological intervention which reduces rumination decreased maladaptive submissive interpersonal behaviour. The implications of the findings are discussed in relation to theory of rumination and interpersonal theories of depression.

No description available.

No description available.