Atmospheric correction of NOAA-11 NDVI data in the arid rangelands of Central Australia

Two empirical approaches to atmospheric correction of NOAA-11 NDVI data are illustrated for the arid lands of Central Australia, using (1) radiosonde data and (2) temperature differences ( T4-T5 ) between bands 4 and 5 of NOAA (split-window). Scattering angle is also shown to influence NDVI data in the Central Australian region. The split-window approach provides the better relationship and can be summarized by a linear formula. The use of preflight or sensor degradation calibrations of bands 1 and 2 have no significant influence on the strength of atmospheric correction procedures tested.     

Multivariate measurement system analysis in multisite testing: An online technique using principal component analysis

Multisite testing improves manufacturing throughput and reduces costs by applying simultaneous testing to products with multiple measurement instruments in parallel. It is important to perform measurement system analysis (MSA) on a multisite testing system to assess its testing capability. Traditional MSA methods are designed to be either univariate or multivariate in a single-site system. They are not capable of analyzing a complex multisite testing system where there are multivariate measurements and multiple instruments in parallel. We propose an online multivariate MSA approach to detecting faulty test instruments in a multisite testing system. In order to pinpoint a faulty test instrument in a multisite testing system we compare the performance of each test instrument to the overall performance of all the parallel instruments in the system. A modified principal component analysis (PCA) method is proposed to transform multivariate measurement data with dependent variables into those with independent principal components. Assuming that all the instruments have the same measurement accuracy and precision we consider a faulty instrument as one whose principal component values are beyond the three sigma control limits of the principal component values of all instruments. We conduct an experiment to provide empirical evidence that the proposed approach is capable of identifying the faulty instruments in a multisite testing system. This approach can be implemented as an online monitoring technique so that production is not interrupted until a faulty instrument is identified.     

Recovering from interruptions: implications for driver distraction research

This research adopted a model of goal activation to study the mechanisms underlying interrupted task performance. The effects of interruption timing, type of interruption, and age on task time and primary task resumption time were explored under conditions in which attention was switched back and forth between two tasks, much as when drivers shift attention between attending to the road and to an in-vehicle task. The timing of interruptions had a significant impact on task resumption times, indicating that the most costly time to interrupt task performance is during the middle of a task. However, this effect was overshadowed by age-related performance decrements for older participants. Interruptions that prevented strategic rehearsal of goals resulted in longer resumption times as compared with interruptions that allowed rehearsal. Actual or potential applications of this research include the design of in-vehicle device user interfaces, the timing of in-vehicle messages, and current metrics for assessing driver distraction.     

Hippocampal lesions impair retention of discriminative responding based on energy state cues.

The present research investigated the hypothesis that the hippocampus is involved with the control of appetitive behavior by interoceptive “hunger” and “satiety” signals. Rats were trained to solve a food deprivation intensity discrimination problem in which stimuli produced by 0-hr and 24-hr food deprivation served as discriminative cues for the delivery of sucrose pellets. For Group 0+, sucrose pellets were delivered at the conclusion of each 4-min session that took place under 0-hr food deprivation, whereas no pellets were delivered during sessions that took place when the rats had been food deprived for 24 hr. Group 24+ received the reverse discriminative contingency (i.e., they received sucrose pellets under 24-hr but not under 0-hr food deprivation). When asymptotic discrimination performance was achieved (indexed by greater incidence of food magazine approach behavior on reinforced compared with nonreinforced sessions), half of the rats in each group received hippocampal lesions, and the remaining rats in each group were designated as sham- or nonlesioned controls. Following recovery from surgery, food deprivation discrimination performance was compared for lesioned and control rats in both Groups 0+ and 24+. Discriminative responding was impaired for rats with hippocampal lesions relative to their controls. This impairment was based largely on elevated responding to nonreinforced food deprivation cues. In addition, hippocampal damage was associated with increased body weight under conditions of ad libitum feeding. The results suggest that the inhibition of appetitive behavior by energy state signals may depend, in part, on the hippocampus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trajectories of psychosocial adjustment in adolescents with spina bifida: A 6-year, four-wave longitudinal follow-up.

Objective: As a follow-up to an earlier cross-sectional study (Holmbeck et al., 2003), the current multimethod, multi-informant investigation examined individual growth in psychosocial adjustment across the adolescent transition in 2 samples: young adolescents with spina bifida (SB) and typically developing adolescents (N = 68 in both groups at Time 1). Method: Growth curve modeling procedures were used to describe the developmental course of psychosocial adjustment across 4 waves of data collection from ages 8 to 15. Child gender was included in the models as a moderator of associations between illness status and adjustment trajectories. Results and Conclusions: Findings revealed that preadolescent differences between groups were maintained for several adjustment variables, indicating that adolescents with SB have enduring academic and attention problems and difficulties with social development (e.g., fewer friends and less influence during family interactions). For other outcomes, trajectories of adjustment levels for adolescents with SB converged on levels observed in comparison adolescents, indicating some areas of resilience. Girls with SB were at risk for increasing levels of social difficulties and negative perceptions of their physical appearance. Clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preadoptive factors predicting lesbian, gay, and heterosexual couples' relationship quality across the transition to adoptive parenthood.

The authors examined preadoptive factors as predictors of relationship quality (love, ambivalence, and conflict) among 125 couples (44 lesbian couples, 30 gay male couples, and 51 heterosexual couples) across the 1st year of adoptive parenthood. On average, all new parents experienced declines in their relationship quality across the 1st year of parenthood regardless of sexual orientation, with women experiencing steeper declines in love. Parents who, preadoption, reported higher levels of depression, greater use of avoidant coping, lower levels of relationship maintenance behaviors, and less satisfaction with their adoption agencies reported lower relationship quality at the time of the adoption. The effect of avoidant coping on relationship quality varied by gender. Parents who, preadoption, reported higher levels of depression, greater use of confrontative coping, and higher levels of relationship maintenance behaviors reported greater declines in relationship quality. These findings have implications for professionals who work with adoptive parents both pre- and postadoption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dyadic coping in metastatic breast cancer.

Objective: Couples facing metastatic breast cancer (MBC) must learn to cope with stressors that can affect both partners’ quality of life as well as the quality of their relationship. Common dyadic coping involves taking a “we” approach, whereby partners work together to maintain their relationship while jointly managing their shared stress. This study prospectively evaluated whether common dyadic coping was associated with less cancer-related distress and greater dyadic adjustment for female MBC patients and their male partners. Design: Couples (N = 191) completed surveys at the start of treatment for MBC (baseline), and 3 and 6 months later. Main Outcome Measures: Cancer-related distress was assessed with the Impact of Events Scale; dyadic adjustment was assessed using the short-form of the Dyadic Adjustment Scale. Results: Multilevel models using the couple as the unit of analysis showed that the effects of common positive dyadic coping on cancer-related distress significantly differed for patients and their partners. Whereas partners experienced slightly lower levels of distress, patients experienced slightly higher levels of distress. Although patients and partners who used more common negative dyadic coping experienced significantly greater distress at all times, the association was stronger for patients. Finally, using more common positive dyadic coping and less common negative dyadic coping was mutually beneficial for patients and partners in terms of greater dyadic adjustment. Conclusion: Our findings underscore the importance of couples working together to manage the stress associated with MBC. Future research may benefit from greater focus on the interactions between patients and their partners to address ways that couples can adaptively cope together. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simulation study of information transmission by multi-unit microelectrode recordings

To analyse the information content of multi-unit signals, cases of two and three superimposed neural responses to a stimulus were simulated. The multi-unit Shannon information rates were compared with those of the constituent single-unit spike trains and also with those of corresponding labelled line signals. The mutual information in the multi-unit response was found to depend on the degree of similarity in the attribute-specific information of the single-unit spike trains. As long as the units were encoding similar attribute-specific information, the multi-unit signal had greater information than any of the individual units. If the units' responses were confounded by different amounts, the multi-unit response could not recover the maximal single-unit information. Labelled line and pooled responses had similar mutual information when the information in the constituent units was similar. However, the normalized gain in information of a labelled line response over a pooled response increased from 27% to 84%, relative to the maximum single-unit information rate, as the difference in constituent single-unit information increased to 100%. Information in single-unit responses is not completely lost when multiple units are superimposed. There are cases in which the union of single-unit spike trains can fully conserve single-unit information and even reduce the effect of confounding information present in the individual responses. More information is available in pairs of responses when the identities of the units are maintained. Summed responses can be used at low informational cost in redundantly encoding clusters of neurons. Higher information losses are incurred as the encoding becomes more independent.     

What aspects of shiftwork influence off-shift well-being of healthcare workers?

Characteristics of shiftwork schedules have implications for off-shift well-being. We examined the extent to which several shift characteristics (e.g., shift length, working sundays) are associated with three aspects of off-shift well-being: work-to-family conflict, physical well-being, and mental well-being. We also investigated whether these relationships differed in four nations. The Survey of Work and Time was completed by 906 healthcare professionals located in Australia, Brazil, Croatia, and the USA. Hierarchical multiple regression analyses supported the hypothesis that shiftwork characteristics account for significant unique variance in all three measures of well-being beyond that accounted for by work and family demands and personal characteristics. The patterns of regression weights indicated that particular shiftwork characteristics have differential relevance to indices of work-to-family conflict, physical well-being, and mental well-being. Our findings suggest that healthcare organizations should carefully consider the implications of shiftwork characteristics for off-shift well-being. Furthermore, although our findings did not indicate national differences in the nature of relationships between shift characteristics and well-being, shiftwork characteristics and demographics for healthcare professionals differ in systematic ways among nations; as such, effective solutions may be context-specific.     

Sensorimotor coordination aftereffects of exposure to a virtual environment

Virtual reality environments (VRs) offer unique training opportunities, particularly for training astronauts and preadapting them to microgravity. The purpose of the current research was to compare disturbances in eye–head–hand (EHH) and eye–head (GAZE) sensorimotor coordination produced by repeated exposures to VR systems. In general, we observed significant increases in position errors in manual target acquisition for both horizontal and vertical targets. We also observed a significant decrement in the ability of subjects to maintain gaze on horizontal eccentric targets immediately after exposure to VR. These preliminary findings provide some direction for developing training schedules for VR users that facilitate adaptation and support the idea that VRs may serve as an analog for sensorimotor effects of spaceflight.