bluuebunny/crossref_metadata_2025_split huggingface dataset:
Embodied dispositions or experience? Identifying new patterns of professional competence
Authors: Rischel Vibeke , Larsen Kristian , Jackson Karen 
Published: February 2008

AbstractTitle.  Embodied dispositions or experience? Identifying new patterns of professional competence Aim.  This paper is a report of a study to explore nurses’ competence as revealed during an admission assessment.Background.  Studies of nursing competence and of models of competence have become virtually synonymous with the five‐stage developmental model applied to nursing by Benner. However, the model has been criticized for its interpretation of intuition and also for the exclusion of the social elements and context of nursing practice.Method.  The study was conducted in 2004. This paper draws on data from 12 structured non‐participant observations of admission assessments in an orthopaedic ward by four nurses: two with <1 year’ experience and two with more than 5 years’ experience. Defined variables were observed using instantaneous and event sampling. The analysis was guided theoretically by the assumptions embedded in Benner’s competence model and Bourdieu’s theory of practice.Findings.  Each nurse had unique patterns of practice that did not correspond to the level of competence expected in relation to their length of experience as a nurse. Nurses’ competence seems to be situational rather than related to levels in the developmental model: in some observed variables, inexperience nurses acted as experts, while experienced nurses acted as advanced beginners, contrary to the expectations of Benner.Conclusion.  The five‐stage developmental competence model could not be verified empirically in this study. The findings suggest that further empirical research is needed to clarify the apparent links between situation and competence.
Parental stress and satisfaction in the non‐tertiary special care nursery
Authors: Foster Jann , Bidewell John , Buckmaster Adam , Lees Sylvia , Henderson‐Smart David 
Published: February 2008

AbstractTitle.  Parental stress and satisfaction in the non‐tertiary special care nursery Aim.  This paper is a report of a study examining the effects of using headbox oxygen and continuous oxygen positive airway pressure treatments for respiratory distress on stress and satisfaction of parents with infants in a special care nursery, and the relationship between parental stress and satisfaction.Background.  Continuous positive airway pressure respiratory support is increasingly used in special care nurseries worldwide. Almost nothing is known about effects of different types of respiratory support on the stress and satisfaction of parents with babies in the special care nursery.Method.  Questionnaires were used from August 2004 to June 2006 in five special care nurseries to measure parental stress using an adaptation of the Parental Stressor Scale: Neonatal Intensive Care Unit and 5‐point scales to measure overall stress and satisfaction.Findings.  Questionnaires were returned from 42 parents of babies receiving headbox oxygen and 51 parents of babies receiving continuous positive airway pressure (62% response rate). High stress was commonly reported. Stress did not differ statistically significantly between the two treatments. Parents with babies receiving continuous positive airway pressure were more satisfied compared to the headbox group. Stress and satisfaction were not statistically significantly correlated.Conclusion.  Clinicians need not favour either method of respiratory support when attempting to minimize parental experience of environmental stress. Further research is needed to test parental stress reduction strategies in the special care nursery.
Concept clarification of neonatal neurobehavioural organization
Authors: Bell Aleeca F. , Lucas Ruth , White‐Traut Rosemary C. 
Published: February 2008

AbstractTitle. Concept clarification of neonatal neurobehavioural organizationAim. This paper is a report of a concept analysis of neonatal neurobehavioural organization for healthy full‐term infants.Background. The neonatal period is an opportune time for researchers and clinicians to assess and intervene for optimal neurobehavioural organization. Yet there is inconsistency and lack of clarity in a scientifically grounded definition of neonatal neurobehavioural organization. Clarification of the concept will strengthen research findings that influence practice for optimal infant development.Method. A concept analysis of the literature between 1939 and 2007 (n = 57) was conducted using Penrod and Hupcey’s principle‐based concept analysis and Morse’s concept clarification.Findings. The concept analysis within and across multiple disciplines revealed: (1) a view of the concept as a holistic phenomenon with multiple dimensions; (2) no agreement on the ideal instrument to operationally define the concept; and (3) consistency in implied meaning, but great variability in terminology. Neonatal neurobehavioural organization was defined as the ability of the neonate to use goal‐directed states of consciousness, in reciprocal interaction with the caregiving environment, to facilitate the emergence of differentiating, hierarchical, and coordinated neurobehavioural systems, with ever‐increasing resiliency and capacity to learn from complex stimuli.Conclusion. A clear conceptual definition will help the international community to communicate effectively within and between disciplines and to apply evidence‐based research findings. It will encourage the development of valid and reliable instruments to capture the concept’s multiple dimensions and direct attention to the infant’s experience, which sculpts early neurobehavioural organization.
Climatic variability alters the outcome of long‐term community assembly
Authors: MacDougall Andrew S. , Wilson Scott D. , Bakker Jonathan D. 
Published: February 2008

SummaryWe used seed additions to test experimentally whether long‐term community assembly unfolds consistently (deterministic model) or whether different outcomes are possible depending on variations in climate and the presence of exotic dominants (stochastic model). The experiment was conducted in homogeneous semi‐arid grassland on the northern Great Plains of North America. Native grass seed additions in each of 3 years (1994–96) were combined factorially with repeated selective herbicide applications to reduce the cover of the extant dominant, a Eurasian C3grass (Agropyron cristatum). We assessed whether composition converged or diverged among treatments between 1996 and 2004.The outcome of long‐term community assembly varied by establishment year, in association with significant variations in monthly growing‐season precipitation from 68‐year averages during the years when seed was added. In 2004, the added native C4grassBouteloua gracilisdominated plots sprayed and seeded in 1994 and 1995, resisting re‐invasion and having significantly higher plot diversity. In contrast, plots sown in 1996 – one of the driest years on record – reverted to the exotic C3grass. Seeded but unsprayed plots maintained their pre‐treatment dominance by exotic grass. Rainfall variability was also associated with the extent of exotic grass cover and bare soil in unsprayed plots, and natural recruitment by native species from nearby prairie.Establishment success varied significantly among the added species. All seeded grasses, other thanB. gracilis, were mostly absent by 2004. The failure of these native C3species to establish appears consistent with deterministic assembly models where local abiotic conditions filter out unsuitable species.Synthesis. Our results indicate that stochastic and deterministic processes operate simultaneously to influence community assembly, depending on interactions among climate, seed availability, species identity and disturbance during the initial stages of establishment. Multiple assembly trajectories developed, but the assembled communities did not include all the added species. Conversion of degraded grassland back to native‐dominated grassland was possible, but only with the removal of the exotic dominant and seed additions during years that were suitably wet for establishment. Once formed, however, the assembled native community resisted re‐invasion. This suggests that native grassland restoration will depend on establishment measures as intense as those used during initial cultivation almost a century earlier.
Spatio‐temporal variation in fruit production and seed predation in a perennial herb influenced by habitat quality and population size
Authors: Ågren Jon , Ehrlén Johan , Solbreck Christer 
Published: February 2008

Summary

In patchily distributed plant species, seed production is likely to be influenced both by local abiotic factors affecting plant size and conditions for fruit maturation, and by population characteristics affecting the intensity of interactions with mutualists and antagonists. However, the relative importance of these effects is poorly known.
We used multiple regression and path models to examine the importance of abiotic factors (sun exposure, soil depth) and population characteristics (size, density and connectivity) for variation in flower and fruit production and intensity of seed predation among 39 populations of the long‐lived herb Vincetoxicum hirundinaria in three consecutive years. In addition, we manipulated water availability in a field experiment and recorded short‐term and long‐term effects on fruit output, and conducted a supplemental hand‐pollination experiment.
Flower production varied little, while fruit initiation, fruit abortion and fruit predation varied considerably among years. Sun exposure and soil depth affected fruit production per plant indirectly and positively through their effects on flower number. Population density affected fruit production negatively through its effect on flower number. Both fruit initiation and the proportion of fruits attacked by the tephritid fly Euphranta connexa were related positively to population size.
The number of full‐size fruits per plant was related positively to sun exposure and population size in two years each, and related negatively to population density in one year. However, because of seed predation, the number of intact mature fruits was related significantly to population characteristics in only one of three years.
The field experiments showed that both shortage of water and insufficient pollination may limit fruit set in V. hirundinaria.
Synthesis. These results demonstrate that the relative importance of local abiotic conditions and population characteristics may vary considerably along the chain of events from flower formation to intact fruit, and also among years. They further show that, at least in species with a naturally patchy distribution, connectivity may be relatively unimportant for variation in reproductive output compared to effects of habitat quality, population size and density.
Effects of plant abundance on reproductive success in the biennial Sabatia angularis (Gentianaceae): spatial scale matters
Authors: Spigler Rachel B. , Chang Shu‐Mei 
Published: February 2008

Summary

Small and low‐density populations often suffer significant reductions in reproduction, as exemplified by studies on rare and threatened species. While this phenomenon is less studied in common species, if general, it should not be restricted to those in peril. We addressed this assertion by examining the effects of plant abundance, measured at population‐level (population size, density) and local‐level (local neighbourhood size, LNS) spatial scales, on fruit set, seed set and subsequent reproductive success (RS) across 19 natural populations of the widespread biennial Sabatia angularis (Gentianaceae). We also examined stigmatic pollen loads across a subset of populations to address whether changes in reproduction were related to reduced pollination.
Effects of plant abundance on reproduction were evident at both spatial scales. At the population level, population size – but not density – affected fruit set significantly. This effect was non‐linear. Fruit set in populations larger than 15 individuals was relatively constant, but dropped abruptly in populations below that size. This relationship did not prevail between population size and RS. Instead, RS declined significantly with population density.
At the local level, increases in LNS between 1‐m and 4‐m radii from study plants increased fruit set significantly. In contrast, increases within 1 m significantly reduced seed set. Both of these effects prevailed at different spatial scales for RS; increases in 1‐m LNS reduced RS, but increases beyond that distance and within 4 m increased RS.
Although non‐significant, trends in the data are consistent with facilitative interactions for pollination influencing local‐level effects on fruit set. However, negative interactions, presumably because of competition for resources, are more important for determining seed set at local scales. Both interactions influence RS, but the effect of competition appears to dominate at the population level.
Synthesis. This study demonstrates that although significant reductions in fruit set in small S. angularis populations imply that common species are not impervious to reproductive disadvantages, small populations need not experience reduced RS. Furthermore, low‐density populations actually enjoy increased RS. As such, this study highlights the complexity of ecological interactions affecting reproduction and the importance of incorporating multiple spatial scales when examining population dynamics.
Differences in the degree of environmental control on large and small tropical plants: just a sampling effect?
Authors: Jones Mirkka M. , Tuomisto Hanna , Olivas Paulo C. 
Published: February 2008

Summary

Tropical rain forest tree species are commonly perceived to have more generalized habitat distributions than understorey species. However, the correspondence between floristic patterns in large trees and smaller understorey plants in relation to environmental differences has rarely been investigated. Comparative analyses are complicated by the fact that tree data are often much more noisy, with higher overall species richness and poorer spatial and temporal representation of species composition within sampling plots.
Using data on trees and pteridophytes collected in 1125 plots located within 6 km2 of lowland rain forest in Costa Rica, we asked: (i) Is there evidence that trees are more generalized in their edaphic and topographic distributions than pteridophytes, and (ii) How much might differences in sampling efficiency affect the results?
We ran community‐level analyses using Mantel tests, and for the five most frequent tree and pteridophyte species we ran logistic regression analyses of species occurrence. To investigate the influence of differing sampling efficiency, the analyses were repeated with four rarefied pteridophyte data sets approximating key structural features of the tree data set.
Differences in community composition in trees and in all pteridophyte data sets were most strongly correlated with environmental differences in the same five soil variables. The most frequent species in both plant groups had non‐random edaphic and topographic distributions.
Both Mantel correlations and the predictive performance of single species models (AUC values) were higher for the full pteridophyte data set than for trees, but these differences were much reduced after pteridophyte rarefaction.
The performance of the species occurrence models calibrated with rarefied pteridophyte data appeared poor when tested on rarefied data. However, their performance in predicting occurrences in the full data set was usually moderate (AUC > 0.70). This suggests that the tree species models may also predict species’ potential habitat distributions better than is apparent from their AUC values.
Synthesis. Our results indicate that rain forest trees and pteridophytes may respond to mesoscale environmental variation in qualitatively similar ways, but that trees will appear much more generalized in their response to the environment unless differences in sampling efficiency are taken into account.
Growth and wood density predict tree mortality in Amazon forests
Authors: Chao Kuo‐Jung , Phillips Oliver L. , Gloor Emanuel , Monteagudo Abel , Torres‐Lezama Armando , Martínez Rodolfo Vásquez 
Published: February 2008

SummaryTree mortality is an important process in forest ecology. We explored the extent to which tropical tree death is a predictable outcome of taxon and individual level properties by means of mixed‐species logistic regression, for trees ≥ 10 cm in diameter. We worked in two lowland forest regions with markedly different floristic composition and dynamic regimes – the high wood density, low‐mortality northeastern (NE) Amazon (in eastern Venezuela), and the low wood density, high‐mortality northwestern (NW) Amazon (in northern Peru).Among those genera that are shared between regions there were no detectable regional differences in mortality rates. This suggests that floristic compositional differences are a major driver of the twofold regional contrast in stand‐level mortality.In NE forests, mortality risk of individual trees is best predicted by low taxon‐level wood density, slow relative growth, and large size, reflecting phylogenetically determined life‐history strategy, physiological stress and senescence.In NW forests, trees with low wood density and slow relative growth are also at most risk, but probability of death is independent of tree size, indicating that senescence is unimportant in this region.Synthesis.This study shows that despite fundamental floristic and dynamic differences between the two Amazonian regions, mortality risk can be predicted with mixed‐species, individual‐based statistical models and that the predictors are remarkably similar, such that tree growth and wood density both play important roles.
The spatiotemporal dynamics of a primary succession
Authors: Cutler N. A. , Belyea L. R. , Dugmore A. J. 
Published: February 2008

Summary

Conceptual models of ecosystem development commonly predict a phase of initial colonization characterized by the nucleation, growth and coalescence of discrete patches of pioneer plants. Spatiotemporal dynamics during subsequent development may follow one of three different models: the classical model, in which initially discrete patches of competitive dominant (secondary) colonists coalesce to form a homogeneous cover; the patch dynamics model, in which renewal mechanisms such as disturbance create a shifting mosaic of patches at different stages; and the geoecological model, in which the vegetation gradually differentiates along edaphic gradients related to the underlying physical template.
These models of spatiotemporal dynamics were tested using vegetation and soil data from an 850‐year chronosequence, comprised of seven lava flows on Mt Hekla, Iceland. The scale and intensity of spatial pattern were quantified on each flow using spatial analyses (mean‐variance ratios, quadrat variance techniques and indices of autocorrelation). Changes in spatial pattern with increasing terrain age were compared with predicted trajectories, in order to identify which of the models of spatiotemporal dynamics was most consistent with the observations.
The early stages of ecosystem development were characterized by colonization of the pioneer species, especially Racomitrium mosses, in discrete patches (‘Pioneer colonization stage’, < 20 years), which then grew laterally and coalesced to form a continuous, homogeneous carpet (‘Pioneer expansion stage’, 20–100 years). Later in the sequence, higher plants established in discrete patches within this pioneer matrix (‘Higher plant colonization stage’, 100–600 years). Over time, heterogeneity re‐emerged at a larger spatial scale as the vegetation differentiated according to topographic variations in the underlying substrate (‘Differentiation stage’, > 600 years).
Synthesis. The spatiotemporal dynamics observed in the early stages of this succession were consistent with a model of pioneer nucleation in micro‐scale safe sites, followed by growth, coalescence and eventual fragmentation of pioneer patches. The spatial patterns which emerged later in development support the geoecological model, with spatial differentiation of vegetation related to meso‐scale substrate topography. The findings provide insight on how vegetation patterns emerge at different stages of ecosystem development in response to differing scales of heterogeneity in the underlying physical environment.
Regulation of Vibrio alginolyticus virulence by the LuxS quorum‐sensing system
Authors: Ye J , Ma Y , Liu Q , Zhao D L , Wang Q Y , Zhang Y X 
Published: February 2008

AbstractQuorum sensing (QS) is a bacterial intercommunication system that controls the expression of multiple genes in response to population density. The LuxS QS system regulates the expression of several virulence factors in a wide variety of pathogenic bacteria. LuxS has been characterized to be responsible for producing a type of autoinducer, AI‐2, which stimulates the expression of the luciferase operon in Vibrio harveyi. Vibrio alginolyticus is established as an opportunistic pathogen of several marine animals, and its LuxS QS system remains undefined. To investigate the pathogenic role of luxS in V. alginolyticus, the luxS mutants of both the standard strain ATCC 33787 and a fish‐clinical isolate MVP01, named MYJS and MYJM, respectively, were constructed. The mutation resulted in reduced lethality to Pagrus major. Intraperitoneal LD50 of MYJS and MYJM increased by 15‐ and 93‐fold, respectively. The two luxS mutants exhibited a lower growth rate and defective flagellar biosynthesis. They also showed a significant decrease in protease production and an increase in both extracellular polysaccharide production and biofilm development. The results suggest that the LuxS QS system plays an important role in regulating the expression of virulence factors in V. alginolyticus.
Effect of temperature on pharmacokinetics of enrofloxacin in mud crab, Scylla serrata (Forsskål), following oral administration
Authors: Fang W H , Hu L L , Yang X L , Hu K , Liang S C , Zhou S 
Published: February 2008

AbstractThe study was conducted to evaluate the pharmacokinetics of enrofloxacin following a single oral gavage (10 mg kg−1) in mud crab, Scylla serrata, at water temperatures of 19 and 26 °C. Enrofloxacin concentration in haemolymph was determined using high‐performance liquid chromatography (HPLC). A multiple and repeated haemolymph sampling from the articular cavity of crab periopods was developed. The haemolymph of an individual crab was successfully sampled up to 11 times from the articular cavity. The profile of haemolymph enrofloxacin concentration of an individual crab versus time was thus achieved. The mean haemolymph enrofloxacin concentration versus time was described by a two‐compartment model with first‐order absorption at two water temperatures. The peak concentrations of haemolymph enrofloxacin at 19 and 26 °C were 7.26 and 11.03 μg mL−1, at 6 and 2 h, respectively. The absorption and distribution half‐life time ( and t1/2α) at 19 °C were 3.7 and 4.5 h, respectively, which were markedly larger than the corresponding values (1.1 and 1.5 h) at 26 °C; the elimination half‐life time (t1/2β) was 79.1 and 56.5 h at 19 and 26 °C, respectively. The area under curve (AUC), total body clearance (Cl) and mean residence time (MRT0–∞) at 19 °C were 636.0 mg L−1 h, 0.016 L h−1 kg−1 and 102.5 h, respectively; the corresponding values at 26 °C were 583.4 mg L−1 h, 0.018 L h−1 kg−1and 63.7 h. These results indicate that enrofloxacin is absorbed and eliminated more rapidly in mud crab at 26 °C than at 19 °C.