bluuebunny/crossref_metadata_2025_split huggingface dataset:
How do children's nurses make clinical decisions? Two preliminary studies
Authors: Twycross Alison , Powls Lucy 
Published: August 2006

Aims and objectives.  To gain an understanding of how children's nurses make clinical decisions.Background.  Several studies have explored how nurses make clinical decisions and the factors that may affect the decision‐making strategies used. However, the results of these studies are contradictory. Further, little is known about children's nurses’ decision‐making strategies.Design.  The think aloud technique.Methods.  Nurses (n = 12) from three surgical wards and nurses (n = 15) from three medical wards in a Scottish children's hospital were presented with clinical scenarios and asked to think aloud. The verbal protocols were analysed to provide an indication of how children's nurses made decisions. Whether there were any differences in decision‐making between experienced and less experienced nurses and between graduates and non‐graduates was also explored.Results.  Analysis of verbal protocols obtained using the think aloud technique suggested that all the nurses in the sample used a hypothetico‐deductive (analytical) model of decision‐making. Further, all participants appeared to use backward reasoning strategies regardless of their level of expertise. This is a characteristic of non‐expert decision‐making. Experienced and less experienced nurses collected similar additional information before planning nursing interventions, supporting the conjecture that they were functioning at a non‐expert level in relation to decision‐making. No differences were seen in the information collected by graduate and non‐graduate nurses.Conclusions.  The decision‐making strategies of children's nurses need exploring further and further research is needed to identify factors that may affect decision‐making strategies. Several strategies to support nurses’ clinical decision‐making have been proposed but need testing to ascertain their effectiveness.Relevance to clinical practice.  In clinical practice nurses make numerous decisions throughout the course of a shift. Sub‐optimal decision‐making strategies may adversely affect the quality of nursing care provided. It is imperative, therefore, to ascertain how nurses make clinical decisions and the factors that may influence the decision‐making strategies used.
The culture of a trauma team in relation to human factors
Authors: Cole Elaine , Crichton Nicola 
Published: August 2006

Aim.  The aim of this ethnographic study was to explore the culture of a trauma team in relation to human factors.Background.  Traumatic injury is the leading cause of death in the first four decades of life in the western world. Evidence suggests that the initial assessment and resuscitation of trauma victims is most successfully carried out by an organized trauma team. Most trauma teams use Advanced Trauma Life Support principles which focus on rapid assessment and management of the patient's injuries. Similarly, most trauma education focuses on Advanced Trauma Life Support principles, concentrating firmly on the patient's physical status. Nevertheless, contemporary literature about emergency teams suggests that human factors, such as communication and interprofessional relationships, can affect the team's performance regardless of how clinically skilled the team members are.Method.  Focused ethnography was used to explore the culture of a trauma team in one teaching hospital. Six periods of observation were undertaken followed by 11 semi‐structured interviews with purposively chosen key personnel. Data from transcripts of the observation field notes and interviews were analysed using open coding, followed by formation of categories resulting in the emergence of six central categories.Results.  Findings suggest that leadership, role competence, conflict, communication, the environment and the status of the patient all influence the culture of the trauma team. Interpretation of these categories suggests that trauma team education should include human factor considerations such as leadership skills, team management, interprofessional teamwork, conflict resolution and communication strategies.Relevance for clinical practice.  The findings suggest that support systems for role development of junior team leaders should be formalized. The proven airline industry techniques of Crew Resource Management, focusing on teamwork and effective communication, could be implemented into continuing professional development for trauma teams to engender collaboration and interprofessional practice.
The dispersal characteristics of the invasive plant Mimulus guttatus and the ecological significance of increased occurrence of high‐flow events
Authors: TRUSCOTT A‐M. , SOULSBY C. , PALMER S. C. F. , NEWELL L. , HULME P. E. 
Published: August 2006

Summary

Increased occurrence of high‐flow events as a result of climate change may affect the dispersal success of an invasive plant species Mimulus guttatus and may result in range expansion. Predicted changes in climate point to a continuation of the recent observed trends in increased precipitation and high‐flow events in Northern Europe.
The study focused on the dispersal characteristics of M. guttatus, and especially the roles of vegetative fragmentation with increasing water velocities, subsequent fragment survival, regeneration and colonization, as well as the buoyancy, survival and germination success of seeds.
M. guttatus was found to fragment readily under velocities typical of high flow conditions and even small fragments had high survival, regeneration and colonization capacity.
Large numbers of small (< 0.02 mg) seeds are produced; however, seeds have a short buoyancy period so the timing and magnitude of high‐flow events is crucial in determining potential dispersal distances. Seeds germinate readily both in water and on sand with an average 33% germination within 9 days.
The dual strategy of dispersal by vegetative fragments and seeds, together with the opportunity of dispersing the two types of propagules during different periods of the year, facilitates local dominance by M. guttatus as well as long‐distance colonization. As a result, the rate of spread of M. guttatus into inundation communities along rivers is likely to increase with more frequent high‐flow events, especially if these coincide with the growing season. Thus, predicting the response of riparian invasive species to environmental change requires not only an understanding of the role of climate in plant demography but also the impact of changes in hydrology on rates of spread.
An unexpected recent ancestor of unisexual Ambystoma
Authors: ROBERTSON ALEXANDER V. , RAMSDEN CADHLA , NIEDZWIECKI JOHN , FU JINZHONG , BOGART JAMES P. 
Published: August 2006

AbstractPrevious research has shown that members of the unisexual hybrid complex of the genus Ambystoma possess a mitochondrial genome that is unrelated to their nuclear parental species, but the origin of this mitochondrion has remained unclear. We used a 744‐bp fragment of the mitochondrial gene cytochrome b within a comparative phylogenetic framework to infer the maternal ancestor of this unisexual lineage. By examining a broader range of species than has previously been compared, we were able to uncover a recent maternal ancestor to this complex. Unexpectedly, Ambystoma barbouri, a species whose nuclear DNA has not been identified in the unisexuals, was found to be the recent maternal ancestor of the individuals examined through the discovery of a shared mtDNA haplotype between the unisexuals and A. barbouri. Based on a combination of sequence data and glacial patterning, we estimate that the unisexual lineage probably originated less than 25 000 years ago. In addition, all unisexuals examined showed extremely similar mtDNA sequences and the resultant phylogeny was consistent with a single origin for this lineage. These results confirm previous suggestions that the unisexual Ambystoma complex was formed from a hybridization event in which the nuclear DNA of the original maternal species was subsequently lost.
Worldwide phylogeography of the blacktip shark (Carcharhinus limbatus) inferred from mitochondrial DNA reveals isolation of western Atlantic populations coupled with recent Pacific dispersal
Authors: KEENEY D. B. , HEIST E. J. 
Published: August 2006

AbstractAlthough many coastal shark species have widespread distributions, the genetic relatedness of worldwide populations has been examined for few species. The blacktip shark, (Carcharhinus limbatus), inhabits tropical and subtropical coastal waters throughout the world. In this study, we examined the genetic relationships of blacktip shark populations (n = 364 sharks) throughout the majority of the species’ range using the entire mitochondrial control region (1067–1070 nucleotides). Two geographically distinct maternal lineages (western Atlantic, Gulf of Mexico, and Caribbean Sea clades, and eastern Atlantic, Indian, and Pacific Ocean clades) were identified and shallow population structure was detected throughout their geographic ranges. These findings indicate that a major population subdivision exists across the Atlantic Ocean, but not the Pacific Ocean. The historical dispersal of this widespread, coastal species may have been interrupted by the rise of the Isthmus of Panama. This scenario implies historical dispersal across the Pacific Ocean (supported by the recovery of the same common haplotype from the Philippines, Hawaii, and the Gulf of California reflecting recent/contemporary dispersal abilities) and an oceanic barrier to recent migration across the Atlantic. Genetic structure within the eastern Atlantic/Indo‐Pacific (ΦST = 0.612, P < 0.001) supports maternal philopatry throughout this area, expanding previous western Atlantic findings. Eastern Atlantic/Indo‐Pacific C. limbatus control region haplotypes were paraphyletic to Carcharhinus tilstoni haplotypes in our maximum‐parsimony analysis. The greater divergence of western Atlantic C. limbatus than C. tilstoni from eastern Atlantic/Indo‐Pacific C. limbatus reflects the taxonomic uncertainty of western Atlantic C. limbatus.
Blind population genetics survey of tropical rainforest trees
Authors: DUMINIL JÉRÔME , CARON HENRI , SCOTTI IVAN , CAZAL SAINT‐OMER , PETIT RÉMY J. 
Published: August 2006

AbstractRainforest tree species can be difficult to identify outside of their period of reproduction. Vascular tissues from Carapa spp. individuals were collected during a short field trip in French Guiana and analysed in the laboratory with nuclear and chloroplast markers. Using a Bayesian approach, > 90% of the samples could be assigned to one of two distinct clusters corresponding to previously described species, making it possible to estimate the genetic structure of each species and to identify cases of introgression. We argue that this blind procedure represents a first‐choice rather than a fallback option whenever related taxa are investigated.
Ménage à trois on Macquarie Island: hybridization among three species of fur seal (Arctocephalusspp.) following historical population extinction
Authors: LANCASTER M. L. , GEMMELL N. J. , NEGRO S. , GOLDSWORTHY S. , SUNNUCKS P. 
Published: August 2006

AbstractHuman‐induced changes to natural systems can cause major disturbances to fundamental ecological and population processes and result in local extinctions and secondary contacts between formerly isolated species. Extensive fur seal harvesting during the nineteenth century on Macquarie Island (subantarctic) resulted in extinction of the original population. Recolonization by three species has been slow and complex, characterized by the establishment of breeding groups of Antarctic and subantarctic fur seals (Arctocephalus gazellaandArctocephalus tropicalis) and presumed nonbreeding (itinerant) male New Zealand fur seals (Arctocephalus forsteri). One thousand and seven pups from eight annual cohorts (1992–2003) were analysed using mitochondrial control region data (RFLP) and 10 microsatellite loci to estimate species composition and hybridization. Antarctic fur seals predominated, but hybridization occurred between all three species (17–30% of all pups). Involvement of New Zealand fur seals was unexpected as females are absent and males are not observed to hold territories during the breeding season. The proportion of hybrids in the population has fallen over time, apparently owing to substantial influxes of pure Antarctic and subantarctic individuals and non‐random mating. Over 50% of New Zealand hybrids and 43% of Antarctic‐subantarctic hybrids were not F1, which indicates some degree of hybrid reproductive success, and this may be underestimated: simulations showed that hybrids become virtually undetectable by the third generation of backcrossing. While human impacts seem to have driven novel hybridization in this population, the present ‘time slices’ analysis suggests some biological resistance to complete homogenization.
Analysis of spatial genetic structure in an expandingPinus halepensispopulation reveals development of fine‐scale genetic clustering over time
Authors: TROUPIN D. , NATHAN R. , VENDRAMIN G. G. 
Published: August 2006

AbstractWe analysed the change of spatial genetic structure (SGS) of reproductive individuals over time in an expandingPinus halepensispopulation. To our knowledge, this is the first empirical study to analyse the temporal component of SGS by following the dynamics of successive cohorts of the same population over time, rather than analysing different age cohorts at a single time. SGS is influenced by various factors including restricted gene dispersal, microenvironmental selection, mating patterns and the spatial pattern of reproductive individuals. Several factors that affect SGS are expected to vary over time and as adult density increases. Using air photo analysis, tree‐ring dating and molecular marker analysis we reconstructed the spread of reproductive individuals over 30 years beginning from five initial individuals. In the early stages, genotypes were distributed randomly in space. Over time and with increasing density, fine‐scale (< 20 m) SGS developed and the magnitude of genetic clustering increased. The SGS was strongly affected by the initial spatial distribution and genetic variation of the founding individuals. The development of SGS may be explained by fine‐scale environmental heterogeneity and possibly microenvironmental selection. Inbreeding and variation in reproductive success may have enhanced SGS magnitude over time.
Effect of the stable thromboxane derivative, carbocyclic thromboxane A2, on membrane potential of rat myenteric neurones in culture
Authors: Rehn M. , Diener M. 
Published: August 2006

Abstract  The effects of carbocyclic thromboxane A2 (cTXA2; 10−6 mol L−1) on membrane potential and cytosolic Ca2+ concentration were measured with the whole‐cell patch‐clamp or the fura‐2 method, respectively, at rat myenteric ganglia. cTXA2 caused a hyperpolarization of myenteric neurones from −19.3 ± 2.5 to −29.3 ± 2.3 mV. In addition, the eicosanoid potentiated the carbachol‐induced depolarization from 4.2 ± 1.0 mV under control conditions to 11.1 ± 1.1 mV in the presence of the cTXA2 (n = 9). The hyperpolarization was abolished by internal application of CsCl (140 mmol L−1), a non‐selective blocker of K+ channels, or EGTA (11 mmol L−1in the pipette solution), a chelator of intracellular Ca2+. A similar inhibition was observed in the presence of charybdotoxin (10−7 mol L−1).Fura‐2 imaging experiments revealed a cTXA2‐evoked increase in the intracellular Ca2+ concentration as indicated by a rise in the fura‐2 ratio signal. This response was mediated by a release of Ca2+ from intracellular stores as sarcoplasmic‐endoplasmic reticulum Ca2+‐ATPase blockade with cyclopiazonic acid (5 × 10−5 mol L−1) completely abolished the response to cTXA2. A similar inhibition was observed after blockade of phospholipase C with U‐73122 (10−5 mol L−1). These results suggest an activation of Ca2+‐activated K+ channels by cTXA2 after stimulation of phospholipase C.
Phospholipase‐dependent signalling during the AvrRpm1‐ and AvrRpt2‐induced disease resistance responses in Arabidopsis thaliana
Authors: Andersson Mats X. , Kourtchenko Olga , Dangl Jeffery L. , Mackey David , Ellerström Mats 
Published: August 2006

SummaryBacterial pathogens deliver type III effector proteins into plant cells during infection. On susceptible host plants, type III effectors contribute to virulence, but on resistant hosts they betray the pathogen to the plant's immune system and are functionally termed avirulence (Avr) proteins. Recognition induces a complex suite of cellular and molecular events comprising the plant's inducible defence response. As recognition of type III effector proteins occurs inside host cells, defence responses can be elicited by in planta expression of bacterial type III effectors. We demonstrate that recognition of either of two type III effectors, AvrRpm1 or AvrRpt2 from Pseudomonas syringae, induced biphasic accumulation of phosphatidic acid (PA). The first wave of PA accumulation correlated with disappearance of monophosphatidylinosotol (PIP) and is thus tentatively attributed to activation of a PIP specific phospholipase C (PLC) in concert with diacylglycerol kinase (DAGK) activity. Subsequent activation of phospholipase D (PLD) produced large amounts of PA from structural phospholipids. This later wave of PA accumulation was several orders of magnitude higher than the PLC‐dependent first wave. Inhibition of phospholipases blocked the response, and feeding PA directly to leaf tissue caused cell death and defence‐gene activation. Inhibitor studies ordered these events relative to other known signalling events during the plant defence response. Influx of extracellular Ca2+ occurred downstream of PIP‐degradation, but upstream of PLD activation. Production of reactive oxygen species occurred downstream of the phospholipases. The data presented indicate that PA is a positive regulator of RPM1‐ or RPS2‐mediated disease resistance signalling, and that the biphasic PA production may be a conserved feature of signalling induced by the coiled‐coil nucleotide binding domain leucine‐rich repeat class of resistance proteins.
A Bsister MADS‐box gene involved in ovule and seed development in petunia and Arabidopsis
Authors: De Folter Stefan , Shchennikova Anna V. , Franken John , Busscher Marco , Baskar Ramamurthy , Grossniklaus Ueli , Angenent Gerco C. , Immink Richard G.H. 
Published: August 2006

SummaryMADS‐domain transcription factors are essential for proper flower and seed development in angiosperms and their role in determination of floral organ identity can be described by the ‘ABC model’ of flower development. Recently, close relatives of the B‐type genes were identified by phylogenetic studies, which are referred to as Bsister (Bs) genes. Here, we report the isolation and characterization of a MADS‐box Bs member from petunia, designated FBP24. An fbp24 knock‐down line appeared to closely resemble the Arabidopsis Bs mutant abs and a detailed and comparative analysis led to the conclusion that both FBP24 and ABS are necessary to determine the identity of the endothelial layer within the ovule. Protein interaction studies revealed the formation of higher‐order complexes between Bs–C–E and Bs–D–E type MADS‐box proteins, suggesting involvement of these specific complexes in determination of endothelium identity. However, although there are many similarities between the two genes and their products and functions, interestingly FBP24 cannot replace ABS in Arabidopsis. The results presented here demonstrate the importance of the comparative analysis of key regulatory genes in various model systems to fully understand all aspects of plant development.
The maize transfer cell‐specific type‐A response regulator ZmTCRR‐1 appears to be involved in intercellular signalling
Authors: Muñiz Luis M. , Royo Joaquín , Gómez Elisa , Barrero Cristina , Bergareche Diego , Hueros Gregorio 
Published: August 2006

SummaryResponse regulators are signal‐transduction molecules present in bacteria, yeast and plants, acting as relays for environmental challenges. This paper reports the characterization of a Zea mays gene, ZmTCRR‐1, that codes for a member of the type‐A response regulator class of proteins. The gene was found to be expressed exclusively in the endosperm transfer‐cell layer 8–14 days after pollination, when transfer‐cell differentiation is most active. The promoter of ZmTCRR‐1 was strongly transactivated in heterologous systems by the transfer cell‐specific transcription factor ZmMRP‐1. The ZmTCRR‐1 protein was detected not only in the transfer‐cell layer, but also in the conductive tissue deep inside the endosperm, where there is no transcription of the gene. This suggests that two‐component systems might be involved in intercellular signal transmission, in contrast to the generally held belief that these systems are involved only in cell‐autonomous pathways.
Distinct patterns of control and expression amongst members of the PEP carboxylase kinase gene family in C4 plants
Authors: Shenton Matt , Fontaine Véronique , Hartwell James , Marsh Justin T. , Jenkins Gareth I. , Nimmo Hugh G. 
Published: August 2006

SummaryWe have examined the complexity of the phosphoenolpyruvate carboxylase kinase (PPCK) gene family in the C4 monocots maize and sorghum. Maize contains at least four PPCK genes. The encoded proteins are similar to other phosphoenolpyruvate carboxylase (PEPC) kinases, in that they comprise a protein kinase domain with minimal extensions, except that two of the proteins contain unusual acidic insertions. The spatial and temporal expression patterns of the genes provide information about their presumed functions. Expression of ZmPPCK1 in leaves is mesophyll cell‐specific and light‐induced, indicating that it encodes the PEPC kinase that is responsible for the phosphorylation of leaf PEPC during C4 photosynthesis. Surprisingly, ZmPPCK2 is expressed in leaf bundle sheath cells, preferentially in the dark. This suggests that a main function of the ZmPPCK2 gene product is to allow PEPC to function anaplerotically in bundle sheath cells in the dark without interfering with the C4 cycle. ZmPPCK2, ZmPPCK3 and ZmPPCK4 are all induced by exposure of tissue to cycloheximide, whereas ZmPPCK1 is not. This suggests that the ZmPPCK2, ZmPPCK3 and ZmPPCK4 genes share the property that their expression is controlled by a rapidly turning over repressor. Sequence and expression data show that sorghum contains orthologues of ZmPPCK1 and ZmPPCK2.
A suite of tools and application notes for in vivo protein interaction assays using bioluminescence resonance energy transfer (BRET)
Authors: Subramanian Chitra , Woo Jongchan , Cai Xue , Xu Xiaodong , Servick Stein , Johnson Carl H. , Nebenführ Andreas , Von Arnim Albrecht G. 
Published: August 2006

SummaryBioluminescence resonance energy transfer (BRET) is a natural biophysical phenomenon that underlies an emerging technique to monitor protein–protein interactions in living cells in real time. Here, we present a series of technical advances to enhance the utility of the BRET assay in plants. A series of recombination cloning vectors was generated to accelerate the expression of proteins tagged with Renilla luciferase or yellow fluorescent protein under transient assay conditions and in stable transgenic plants. Working in stably transformed Arabidopsis or tobacco, we then detected BRET between three pairs of candidate interaction partners: dimerization of the E3 ubiquitin ligase COP1, interaction between COP1 and the B‐box protein STH, and interaction between the light regulatory bZip transcription factors HY5 and HYH. A codon‐optimized version of the Renilla luciferase gene resulted in improved expression in Arabidopsis. Renilla luciferase was active in a variety of subcellular organelles, including plastids, mitochondria, peroxisomes and Golgi stacks. In a survey of the Arabidopsis light signaling machinery as a model system, we estimated the likelihood that a known protein–protein interaction can be documented using BRET. Finally, we show that Renilla luciferase may serve as a reporter of protein stability in a cycloheximide chase assay.