bluuebunny/crossref_metadata_2025_split huggingface dataset:
Involvement of nurses in physician‐assisted dying
Authors: Bilsen Johan J.R. , Vander Stichele Robert H. , Mortier Freddy , Deliens Luc 
Published: August 2004

Background.  Death in modern societies is often preceded by medical end‐of‐life decisions. Empirical research on these end‐of‐life decisions focuses predominantly on the physicians’ role. Little is known about the role of other health care workers, especially that of nurses.Aim.  This paper reports the findings of a study that investigated how often nurses are consulted by physicians in the decision‐making process preceding end‐of‐life decisions and how often nurses participate in administering lethal drugs in end‐of‐life decisions.Method.  Data were collected within a nationwide cross‐sectional retrospective death certificate study in Flanders, the Dutch‐speaking part of Belgium. We selected 3999 deaths, a 20% random sample of all those occurring during the first 4 months of 1998. Anonymous questionnaires were mailed to the physicians who signed the death certificates. Several questions concerned the involvement of nurses in end‐of‐life decisions.Results.  We received 1925 valid questionnaires. For all reported end‐of‐life decisions (39·3% of all deaths in Flanders), physicians provided information about the involvement of nurses. Physicians consulted at least one nurse in 52% of end‐of‐life decisions cases occurring in institutions, compared with 21·4% of such cases at home. Nurses administered lethal drugs in 58·8% of euthanasia cases occurring in institutions and in 17·2% at home. For cases in which life was ended without the patient's explicit request because, predominantly, they were too ill to do so, these percentages were respectively 82·7% and 25·2%. In institutions, nurses mostly administered drugs without the attendance of a physician who had prescribed the drugs.Conclusions.  Nurses in Belgium are largely involved in administering lethal drugs in end‐of‐life decisions, while their participation in the decision‐making process is rather limited. To guarantee prudent practice in end‐of‐life decisions, we need clear guidelines, professionally supported and legally controlled, for the assignment of duties between physicians and nurses regarding the administration of lethal drugs to reflect current working practice. In addition, we need appropriate binding standards governing mutual communication about all end‐of‐life decisions.
Palliative care nurses’ views on euthanasia
Authors: Verpoort Charlotte , Gastmans Chris , Casterlé Bernadette Dierckx de 
Published: August 2004

Background.  In debates on euthanasia legalization in Belgium, the voices of nurses were scarcely heard. Yet studies have shown that nurses are involved in the caring process surrounding euthanasia. Consequently, they are in a position to offer valuable ideas about this problem. For this reason, the views of these nurses are important because of their palliative expertise and their daily confrontation with dying patients.Aim.  The aim of this paper is to report a study of the views of palliative care nurses about euthanasia.Methods.  A grounded theory approach was chosen, and interviews were carried out with a convenience sample of 12 palliative care nurses in Flanders (Belgium). The data were collected between December 2001 and April 2002.Findings.  The majority of the nurses were not a priori for or against euthanasia, and their views were largely dependent on the situation. What counted was the degree of suffering and available palliative options. Depending on the situation, we noted both resistance and acceptance towards euthanasia. The underlying arguments for resistance included respect for life and belief in the capabilities of palliative care; arguments underlying acceptance included the quality of life and respect for patient autonomy. The nurses commented that working in palliative care had a considerable influence on one's opinion about euthanasia.Conclusion.  In light of the worldwide debate on euthanasia, it is essential to know how nurses, who are confronted with terminally ill patients every day, think about it. Knowledge of these views can also contribute to a realistic and qualified view on euthanasia itself. This can be enlightening to the personal views of caregivers working in a diverse range of care settings.
Use of intuition by nursing students: instrument development and testing
Authors: Smith Anita J. , Thurkettle Mary Ann , Cruz Felicitas A. dela 
Published: August 2004

Background.  Intuition has been described as an important type of nursing knowledge and has gained acceptance as a valid way of knowing in clinical nursing. Use of intuition has become one way of explaining professional expertise. Measures of the use of intuition have been developed primarily for experienced nurses, but few measures of intuition use among nursing students exist.Aim.  The aim of this paper is to describe the development and psychometric testing of an instrument to measure use of intuition by nursing students.Methods.  Instrument development consisted of concept clarification, item development, and psychometric testing. Intuition was defined as a non‐linear process of knowing perceived through physical awareness, emotional awareness, and/or through physical or spiritual connections. Initial measurement items were derived inductively from the literature and informal interviews with senior nursing students. Seven content experts established a content validity index of 0·86 for the initial 33‐item measure. It was pretested with a sample of 20 senior nursing students prior to its nationwide validation with a random sample of 1000 senior bachelor of science and associate degree nursing students.Results.  Postal mail data collection resulted in 349 responses (35% response rate). Principal component analysis with orthogonal varimax rotation resulted in seven factors accounting for 66·2% of the variance: physical sensations (28·4%); premonitions (9·7%); spiritual connections (7·7%); reading of cues (6.1%); sensing energy (5·7%); apprehension (4·3%); and reassuring feelings (4%). Eigenvalues ranged from 1 to 7·1 and factor loadings ranged from 0·534 to 0·858. The validation resulted in a revised 25‐item measure that demonstrated an overall Cronbach's alpha of 0·89 and a range of 0·69–0·84 for each factor. The study is limited by the use of a self‐report measure and the attrition in the randomized sample.Conclusions.  The intuition measure for use with students showed evidence of construct validity and reliability. With further testing, the measure could serve as a stimulus to foster students’ intuitive abilities.
Learning to nurse children: towards a model for nursing students
Authors: Coetzee Minette 
Published: August 2004

Background.  As undergraduate nursing students approach their paediatric placement, their anticipation ranges from keen expectation to anxious avoidance. This placement has been described as the most stressful in nursing programmes. While various nurse scholars have attempted to describe the practice and the theory of nursing, it has been the challenge of nurse teachers to weave the theory and practice of nursing together for their students. The nature of this learning is, however, still being explored.Aim.  This paper reports a study whose aim was to describe, and propose a theoretical understanding of, how nursing students learn to care for children.Method.  In this grounded theory study, participants were drawn from four consecutive student groups in their third year of a Bachelor of Nursing programme. Data included participant observation, focus groups and student descriptions, from both personal reflective journals and narratives. The qualitative research paradigm and the interlaced, often simultaneous, roles of researcher and teacher defined the design and implementation of the study.Findings.  Data analysis confirmed the complex nature of students’ learning to care. The relationships that they established with children and others (families, peers, clinical nurses and lecturers) whom they encountered emerged as key in their learning. The social process that was central to student learning was working out how to connect with a child in their care: puzzling out a connection. Each connection with a child contributed to the next and thus to the student's learning. Each connection also contributed to the student's resources, knowledge and experience base, adding to learning by further equipping the student for the next encounter with a child.Conclusion.  The resulting theory contributes towards understanding the complexity of learning to care for children. The relational nature of learning shown in this work can guide the structuring and evaluation of learning environments in child nursing programmes. The context of interpersonal relationships of students when learning to care for children provides evidence for re‐examining how nurse teachers facilitate and evaluate student learning in child nursing programmes.
Sugar maple (Acer saccharum Marsh.) establishment in boreal forest: results of a transplantation experiment
Authors: Kellman Martin 
Published: August 2004

AbstractAim  To evaluate whether seedlings of sugar maple (Acer saccharum Marsh.) can establish beyond the species northern range limit in adjacent boreal forest.Location  The hardwood–boreal forest transition zone on the north‐east shore of Lake Superior, Ontario, Canada.Methods  Seed fall of sugar maple was monitored for 5 years in a stand of this species at its northern range limit, and seed from this stand was transplanted to five micro‐habitat types in an adjacent boreal forest. The establishment and survival of sugar maple seedlings there, and in the seed‐source stand, was monitored for the following 7–11 years. Soil‐surface light levels were measured in both forest types.Results  Most seed fell in the final year of monitoring, when c. 250 seeds m−2 were recorded. First‐year seedling establishment rates in the maple stand, deriving from this mast seed year, was approximately double that deriving from seed transplanted to the boreal forest sites; this is tentatively attributed to seed predator satiation in the maple stand. However, subsequent seedling survivorship in the boreal forest was greater than that in the maple stand, resulting in comparable seedling densities by the end of 6 years. This difference is tentatively attributed to better illumination in the boreal forest sites, and canopy‐opening disturbances appear to be especially facilitative of seedling survival.Main conclusions  There is no fundamental impediment to sugar maple seedlings establishing in boreal forest communities if climate warming occurs and seed is available. If management intervention is needed to accelerate seed availability in a rapidly warming boreal forest, then diffuse seed application to disturbed boreal forest sites during mast years of local boreal tree species is recommended as the most effective way of avoiding seed predation and increasing seedling survival.
ExoU is a potent intracellular phospholipase
Authors: Sato Hiromi , Frank Dara W. 
Published: August 2004

SummaryThe combination of a large genome encoding metabolic versatility and conserved secreted virulence determinants makes Pseudomonas aeruginosa a model pathogen that can be used to study host–parasite interactions in many eukaryotic hosts. One of the virulence regulons that likely plays a role in the ability of P. aeruginosa to avoid innate immune clearance in mammals is a type III secretion system (TTSS). Upon cellular contact, the P. aeruginosa TTSS is capable of delivering a combination of at least four different effector proteins, exoenzyme S (ExoS), ExoT, ExoU, and ExoY. Two of the four translocated proteins, ExoS and ExoU, are cytotoxic to cells during infection and transfection. The mechanism of cytotoxicity of ExoS is unclear. ExoU, however, has recently been characterized as a member of the phospholipase A family of enzymes, possessing at least phospholipase A2 activity. Similar to ExoS, ExoT and ExoY, ExoU requires either a eukaryotic‐specific modification or cofactor for its activity in vitro. The biologic effects of minimal expression of ExoU in yeast can be visualized by membrane damage to different organelles and fragmentation of the vacuole. In mammalian cells, the direct injection of ExoU causes irreversible damage to cellular membranes and rapid necrotic death. ExoU likely represents a unique enzyme and is the first identified phopholipase virulence factor that is translocated into the cytosol by TTSS.
Respiration metabolism reduces oxidative and acid stress to improve long‐term survival of Lactococcus lactis
Authors: Rezaïki Lahcen , Cesselin Bénédicte , Yamamoto Yuji , Vido Karin , Van West Evelien , Gaudu Philippe , Gruss Alexandra 
Published: August 2004

SummaryThe impact of oxygen on a cell is strongly dependent on its metabolic state: survival in oxygen of free‐living Lactococcus lactis, best known as a fermenting, acidifying bacterium, is generally poor. In contrast, if haem is present, L. lactis uses oxygen to switch from fermentation to respiration metabolism late in growth, resulting in spectacularly improved long‐term survival. Oxygen is thus beneficial rather than detrimental for survival if haem is provided. We examined the effects of respiration on oxygen toxicity by comparing integrity of stationary phase cells after aerated growth without and with added haem. Aeration (no haem) growth caused considerable cellular protein and chromosomal DNA damage, increased spontaneous mutation frequencies and poor survival of recA mutants. These phenotypes were greatly diminished when haem was present, indicating that respiration constitutes an efficient barrier against oxidative stress. Using the green fluorescent protein as an indicator of intracellular oxidation state, we showed that aeration growth provokes significantly greater oxidation than respiration growth. Iron was identified as a main contributor to mortality and DNA degradation in aeration growth. Our results point to two features of respiration growth in lactococci that are responsible for maintaining low oxidative damage: One is a more reduced intracellular state, which is because of efficient oxygen elimination by respiration. The other is a higher pH resulting from the shift from acid‐forming fermentation to respiration metabolism. These results have relevance to other bacteria whose respiration capacity depends on addition of exogenous haem.
Functional domains of the IS1 transposase: analysis in vivo and in vitro
Authors: Ton‐Hoang Bao , Turlan Catherine , Chandler Michael 
Published: August 2004

SummaryThe IS1 bacterial insertion sequence family, considered to be restricted to Enterobacteria, has now been extended to other Eubacteria and to Archaebacteria, reviving interest in its study. To analyse the functional domains of the InsAB′ transposase of IS1A, a representative of this family, we used an in vivo system which measures IS1‐promoted rescue of a temperature‐sensitive pSC101 plasmid by fusion with a pBR322::IS1 derivative. We also describe the partial purification of the IS1 transposase and the development of several in vitro assays for transposase activity. These included a DNA band shift assay, a transposase‐mediated cleavage assay and an integration assay.  Alignments  of  IS  family  members  (http://www‐is.biotoul.fr) not only confirmed the presence of an N‐terminal helix–turn–helix and a C‐terminal DDE motif in InsAB′, but also revealed a putative N‐terminal zinc finger. We have combined the in vitro and in vivo tests to carry out a functional analysis of InsAB′ using a series of site‐directed InsAB′ mutants based on these alignments. The results demonstrate that appropriate mutations in the zinc finger and helix–turn–helix motifs result in loss of binding activity to the ends of IS1 whereas mutations in the DDE domain are affected in subsequent transposition steps but not in end binding.
Redox and antioxidant systems of the malaria parasite Plasmodium falciparum
Authors: Müller Sylke 
Published: August 2004

SummaryThe malaria parasite Plasmodium falciparum is highly adapted to cope with the oxidative stress to which it is exposed during the erythrocytic stages of its life cycle. This includes the defence against oxidative insults arising from the parasite's metabolism of haemoglobin which results in the formation of reactive oxygen species and the release of toxic ferriprotoporphyrin IX. Central to the parasite's defences are superoxide dismutases and thioredoxin‐dependent peroxidases; however, they lack catalase and glutathione peroxidases. The vital importance of the thioredoxin redox cycle (comprising NADPH, thioredoxin reductase and thioredoxin) is emphasized by the confirmation that thioredoxin reductase is essential for the survival of intraerythrocytic P. falciparum. The parasites also contain a fully functional glutathione redox system and the low‐molecular‐weight thiol glutathione is not only an important intracellular thiol redox buffer but also a cofactor for several redox active enzymes such as glutathione S‐transferase and glutaredoxin. Recent findings have shown that in addition to these cytosolic redox systems the parasite also has an important mitochondrial antioxidant defence system and it is suggested that lipoic acid plays a pivotal part in defending the organelle from oxidative damage.
Environmental conditions influencing Sclerotinia sclerotiorum infection and disease development in lettuce
Authors: Young C. S. , Clarkson J. P. , Smith J. A. , Watling M. , Phelps K. , Whipps J. M. 
Published: August 2004

The environmental factors that influence infection of lettuce by ascospores of Sclerotinia sclerotiorum, and subsequent disease development, were investigated in controlled environment and field conditions. When lettuce plants were inoculated with a suspension of ascospores in water or with dry ascospores and exposed to a range of wetness durations or relative humidities at different temperatures, all plants developed disease but there was no relationship between leaf wetness duration or humidity and percentage of diseased plants. Ascospores started to germinate on lettuce leaves after 2–4 h of continuous leaf wetness at optimum temperatures of 15–25°C. The rate of development of sclerotinia disease and the final percentage of plants affected after 50 days were greatest at 16–27°C, with disease symptoms first observed 7–9 days after inoculation, and maximum final disease levels of 96%. At lower temperatures, 8–11°C, disease was first observed 20–26 days after inoculation, with maximum final disease levels of 10%. Disease symptoms were always observed first at the stem base. In field‐grown lettuce in Norfolk, 2000 and 2001, inoculated with ascospore suspensions, disease occurred only in lettuce planted in May and June, with a range of 20–49% of plants with disease by 8 weeks after inoculation. In naturally infected field‐grown lettuce in Cheshire, 2000, disease occurred mainly in lettuce planted throughout May, with a maximum of 31% lettuce diseased within one planting, but subsequent plantings had little (≤ 4%) or no disease. Lack of disease in the later plantings in both Norfolk and Cheshire could not be attributed to differences in weather factors.
Genetic variation and covariation for aggressiveness, deoxynivalenol production and fungal colonization among progeny of Gibberella zeae in wheat
Authors: Cumagun C. J. R. , Rabenstein F. , Miedaner T. 
Published: August 2004

Gibberella zeae (anamorph Fusarium graminearum) causes head blight of cereals and contaminates grains with mycotoxins such as deoxynivalenol (DON). To determine the correlations among aggressiveness traits, fungal colonization and DON production, 50 progeny from a segregating population of G. zeae were inoculated onto a susceptible winter wheat cultivar in three field environments (year–location combinations). Aggressiveness traits were measured as head‐blight rating and plot yield relative to noninoculated plots. Fungal colonization, measured as Fusarium exoantigen (ExAg) content, and DON production were analysed with two ELISA formats. Disease severity was moderate to high based on head‐blight rating and relative plot yield. Fusarium ExAg content and DON production ranged from 0·26–1·41 units and from 4·18–43·70 mg kg−1, respectively. Significant (P = 0·01) genotypic variation was found for all traits. Heritability for Fusarium ExAg content was rather low because of high progeny–environment interaction and error. DON/Fusarium ExAg ratio did not vary significantly (P > 0·1) among progeny. Correlation between DON production and Fusarium ExAg content across environments was high (r = 0·8, P = 0·01), but no covariation existed between aggressiveness traits and DON/Fusarium ExAg content ratio.
Linkage of Vfa4 in Malus × domestica and Malus floribunda with Vf resistance to the apple scab pathogen Venturia inaequalis
Authors: Afunian M. R. , Goodwin P. H. , Hunter D. M. 
Published: August 2004

The Vf locus from Malus floribunda clone 821 is an important source of resistance to apple scab disease caused by Venturia inaequalis, and has been introduced into numerous cultivars of domesticated apple, Malus × domestica. Cloning of the putative Vf locus has revealed that it contains several receptor‐like Vf candidate genes. In order to determine which of these genes is most closely linked to Vf resistance, primers were designed based on conserved regions in the Vf candidate genes adjacent to a variable portion of the leucine‐rich repeat (LRR) domain, to yield PCR product length polymorphisms. PCR products were obtained from 31 cultivars of M. × domestica, of which 19 are known to contain Vf resistance, and from 10 selections of M. floribunda. PCR products corresponding in size to Vfa1 and Vfa2 were found in all the plants tested. However, a PCR product with 100% predicted amino acid identity to Vfa4 was found only in M. ×domestica cultivars known to have Vf scab resistance. This PCR product was also found in most, but not all, selections of M. floribunda tested, including the original source of Vf resistance, M. floribunda 821. The PCR product matching Vfa4 appears to be the most closely linked to Vf resistance and should be a valuable tool for monitoring Vf inheritance in apple.
Relationship of genetic structure of Pseudomonas savastanoi pv. savastanoi populations from Italian olive trees and patterns of host genetic diversity
Authors: Scortichini M. , Rossi M. P. , Salerno M. 
Published: August 2004

A total of 360 Pseudomonas savastanoi pv. savastanoi isolates obtained from 11 Italian olive (Olea europaea) cultivars grown in different provinces were assessed with repetitive PCR using short interspersed elements of the bacterial genome as primers (ERIC, BOX and REP primer sets). The population structure of the isolates was determined by using three different hierarchical clustering algorithms: UPGMA, single‐link and complete‐link methods. REP primers were the most discriminatory. The various fingerprints obtained from the same cultivar and locality persisted over 2 years of knot sampling. Repetitive PCR and UPGMA analysis, using the three data sets combined, revealed 20 patterns with an overall similarity of 81%, with no grouping of the isolates. The resulting dendrogram shows a bush‐like topology. Similar results were obtained with the other two clustering methods. In contrast, data obtained from the literature showed that the genetic structure of olive is characterized by bifurcated dendrograms and clear grouping of cultivars. Therefore it appears that the host plant and its pathogen did not cospeciate. The strict adaptation of the bacterium to olive would represent a case of association by colonization.