bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of customization of master gutta‐percha cone on apical control of root filling using different techniques: an ex vivo study
Authors: Van Zyl S. P. , Gulabivala K. , Ng Y.‐L. 
Published: August 2005

AbstractAims  (i) To compare the prevalence of extrusion of root filling material when placed using different root filling techniques, with or without customization of the master gutta‐percha (GP) cone; and (ii) to investigate the effects of some factors influencing root filling extrusion and presence of voids.Methodology  A total of 180 roots were selected, prepared and randomly allocated to three groups. Five general dental practitioners performed the root fillings; each filled one group of roots (n = 60) using each of three techniques; ‘cold lateral compaction’ (n = 20), ‘warm vertical compaction’ (n = 20) and ‘continuous‐wave’ (n = 20) techniques. For each obturation technique, the master GP cone was customized using chloroform in 10 samples. Two groups of the roots were recycled to allow all five operators to fulfill their remit. Two observers, blind to operator and obturation technique, examined the radiographs (master apical file, post‐obturation) to determine the presence of root filling extrusion and voids within the apical 5 mm, independently. Root filling extrusion was also confirmed by direct inspection of the root apex after obturation. The data were analysed using logistic regression models.Results  A total of 300 root fillings were performed; nine were excluded from the analysis. Most of the root fillings (80%, n = 233) were placed within 0.5 mm of the working length; only 20% (n = 58) were placed >0.5 mm beyond the working length. The odds of prevalence of extrusion (>0.5 mm) were significantly reduced by about 50% when cold lateral compaction or customization of GP were used. One operator produced 2.5 times more extruded root fillings than others. Curvature & length of root canal, apical size of prepared canal, as well as operator's preferred obturation technique had no significant influence on the prevalence of extrusion. Customization of GP was the sole factor to significantly reduce the prevalence of voids within the apical 5 mm of working length.Conclusions  Root filling extrusion was significantly influenced by ‘operator’ and was reduced by cold lateral compaction and customization of the master cone. Customization of master cone was the only factor that reduced voids apically.
Effect of E. faecalis on the release of serine proteases elastase and cathepsin G, and collagenase‐2 (MMP‐8) by human polymorphonuclear leukocytes (PMNs)
Authors: Reynaud af Geijersstam A. , Sorsa T. , Stackelberg S. , Tervahartiala T. , Haapasalo M. 
Published: August 2005

AbstractAim  To measure the release of hydrolytic enzymes [elastase, cathepsin G and collagenase‐2 (MMP‐8)] from human polymorphonuclear leukocytes (PMNs) during interaction with strains of Enterococcus faecalis isolated from endodontic infections.Methodology  Six E. faecalis strains isolated from treatment resistant cases of apical periodontitis were included in the study. Overnight cultures of the microbes were used for the experiments. PMNs were isolated using the Ficoll Paque technique, and their vitality was assessed throughout the experiments by the Trypan Blue exclusion test. A known amount of microbes and PMNs were mixed in PBS at +37 °C in air, and the release of elastase, cathepsin G and MMP‐8 was measured at 0, 20, 60 and 120 min after initiation of incubation. The activities of elastase and cathepsin G were analysed by spectrophotometer assays using specific synthetic peptide substrates, and MMP‐8 by western immunoblotting quantitated by computer densitometry. PMNs incubated in buffer without any added microbes served as negative controls, cells incubated with 5 ng mL−1 phorbol myristic acetate (PMA) served as a positive control. The 95% confidence interval was used to compare the relative amount of elastase and cathepsin G released from the samples.Results  One E. faecalis strain induced a similar or higher elastase, cathepsin G and MMP‐8 release than the positive control, whereas the other five strains induced only moderate or no release of the three enzymes examined as compared with the negative and positive controls. Western immunoblot revealed that released MMP‐8 had molecular sizes of 60 and 75 kDa representing active and latent forms of MMP‐8. In addition, >110 kDa high molecular size and a fragmented 20–30 kDa MMP‐8 species could be observed.Conclusions  The majority of the E. faecalis strains induced little or no release of hydrolytic enzymes from the PMN cells. The finding may partly explain the clinical observation that root canal infections dominated by E. faecalis are usually symptom free.
Response and adaptation of different methanotrophic bacteria to low methane mixing ratios
Authors: Knief Claudia , Dunfield Peter F. 
Published: August 2005

SummaryDescribed genera of methanotrophic bacteria are present in most upland soils, but it is not known whether these are sufficiently oligotrophic to oxidize methane at its trace atmospheric mixing ratio of 1.75 ppmv. Members of the genera Methylocystis, Methylosinus, Methylocaldum and Methylobacter were isolated from different upland soils and compared with type strains for growth and activity under low methane mixing ratios. The specific affinity (a0s) varied by about one order of magnitude among different methanotrophs. It was highest in some Methylocystis spp., suggesting that these were the most oligotrophic. In direct tests, the threshold mixing ratio of methane required by most methanotrophs for growth ranged from 100 to greater than 1000 ppmv. However, two Methylocystis strains grew at only 10–100 ppmv of methane and one oxidized atmospheric methane for >  3 months with little or no decline in the absolute rate. The results show that some cultivated methanotrophic bacteria are much more oligotrophic than others, and may contribute to atmospheric methane oxidation in soils. However, it is likely that these need additional energy sources for long‐term survival, and that uncultivated groups of methanotrophic bacteria are primarily responsible for the process in soils possessing high methane oxidation rates.
Evolutionary innovation: a bone‐eating marine symbiosis
Authors: Goffredi Shana K. , Orphan Victoria J. , Rouse Greg W. , Jahnke Linda , Embaye Tsegeria , Turk Kendra , Lee Ray , Vrijenhoek Robert C. 
Published: August 2005

SummarySymbiotic associations between microbes and invertebrates have resulted in some of the most unusual physiological and morphological adaptations that have evolved in the animal world. We document a new symbiosis between marine polychaetes of the genus Osedax and members of the bacterial group Oceanospirillales, known for heterotrophic degradation of complex organic compounds. These organisms were discovered living on the carcass of a grey whale at 2891 m depth in Monterey Canyon, off the coast of California. The mouthless and gutless worms are unique in their morphological specializations used to obtain nutrition from decomposing mammalian bones. Adult worms possess elaborate posterior root‐like extensions that invade whale bone and contain bacteriocytes that house intracellular symbionts. Stable isotopes and fatty acid analyses suggest that these unusual endosymbionts are likely responsible for the nutrition of this locally abundant and reproductively prolific deep‐sea worm.
The molecular diversity of freshwater picoeukaryotes from an oligotrophic lake reveals diverse, distinctive and globally dispersed lineages
Authors: Richards Thomas A. , Vepritskiy Alexey A. , Gouliamova Dilnora E. , Nierzwicki‐Bauer Sandra A. 
Published: August 2005

SummaryThe recent discovery of a diverse phylogenetic assemblage of picoeukaryotes from environments such as oceans, salt marshes and acidic habitats, has expanded the debates about the extent and origin of microbial eukaryotes. However, the diversity of these eukaryote microorganisms, that overlap bacteria in size, and their environmental and biogeographical ubiquity remains poorly understood. Here we survey picoeukaryotes (microbial eukaryotes of 0.2–5 µm in size) from an oligotrophic (nutrient deficient) freshwater habitat using ribosomal RNA gene sequences. Three taxonomic groups the Heterokonta, Cryptomonads and the Alveolata dominated the detected diversity. Most sequences represented previously unsampled species, with several being unassignable to known taxonomic groups and plausibly represent new or unsampled phyla. Many freshwater phylogenetic groups identified in this study appeared unrelated to picoeukaryotic sequences identified in marine ecosystems, suggesting that aspects of eukaryote microbial diversity are specific to certain aquatic environments. Conversely, at least five phylogenetic clusters comprised sequences from freshwater and globally dispersed and often contrasting environments, supporting the concept that a number of picoeukaryotic lineages are widely distributed.
Coupling 16S‐ITS rDNA clone libraries and automated ribosomal intergenic spacer analysis to show marine microbial diversity: development and application to a time series
Authors: Brown Mark V. , Schwalbach Michael S. , Hewson Ian , Fuhrman Jed A. 
Published: August 2005

SummaryWe outline an approach to simultaneously assess multilevel microbial diversity patterns utilizing 16S‐ITS rDNA clone libraries coupled with automated ribosomal intergenic spacer analysis (ARISA). Sequence data from 512 clones allowed estimation of ARISA fragment lengths associated with bacteria in a coastal marine environment. We matched 92% of ARISA peaks (each comprising > 1% total amplified product) with corresponding lengths from clone libraries. These peaks with putative identification accounted for an average of 83% of total amplified community DNA. At 16S rDNA similarities < 98%, most taxa displayed differences in ARISA fragment lengths > 10 bp, readily detectable and suggesting ARISA resolution is near the ‘species’ level. Prochlorococcus abundance profiles from ARISA were strongly correlated (r 2 = 0.86) to Prochlorococcus cell counts, indicating ARISA data are roughly proportional to actual cell abundance within a defined taxon. Analysis of ARISA profiles for 42 months elucidated patterns of microbial presence and abundance providing insights into community shifts and ecological niches for specific organisms, including a coupling of ecological patterns for taxa within the Prochlorococcus, the Gamma Proteobacteria and Actinobacteria. Clade‐specific ARISA protocols were developed for the SAR11 and marine cyanobacteria to resolve ambiguous identifications and to perform focused studies. 16S‐ITS data allowed high‐resolution identification of organisms by ITS sequence analysis, and examination of microdiversity.
Hindrance for patient participation in nursing care
Authors: Sahlsten Monika J.M. , Larsson Inga E. , Plos Kaety A.E. , Lindencrona Catharina S.C. 
Published: August 2005

The study's rationale: Patients’ influence in health care through participation, freedom of choice and information, is laid down in laws, national and local directives. In nursing care situations, the degree to which a patient participates depends on the nursing staff. Accordingly, hindrances for patient's participation during nursing care is an important question for the nursing profession.Aims and objectives: The aim was to focus on Swedish Registered Nurses opinion of hindrances for patient participation in nursing care and to uncover the informants’ perspectives in depth.Methodological design and justification: The study was limited to inpatient somatic care and has a qualitative approach. Data were collected through seven focus group interviews with 31 Registered Nurses from five hospitals. An analysis of the tape‐recorded interview material was made, combining elements of content analysis with aspects of the Grounded Theory approach.Ethical issues and approval: The ethics of scientific work was followed. The participants gave informed consent. Verbal and written information was given as a guarantee that all information would be treated confidentially outside the focus group. Formal approval by ethical committee was not required according to national and local directives.Results: Hindrance for patient participation in nursing care comprised three themes: Competence, Influence of significant others and Organization and work environment, and their seven underlying subthemes.Conclusions: The study clarified factors, which individually or combined may be hindrance for patient participation in nursing practice. Professional nurses must be able to find a balance for their patients’ participation in nursing care activities through identification and coping with the hindrances. The three themes and seven subthemes here identified, can be used in patient care and its’ evaluation, like also quality assurance of care and work organization and in nursing education. For further development replication studies are needed, like additional studies of patients and significant others.
Swedish child health care in a changing society
Authors: Hallberg Ann‐Christine , Lindbladh Eva , Petersson Kerstin , Råstam Lennart , Håkansson Anders 
Published: August 2005

Background:  Staff in Swedish child health care today feel a gap between policy and practice. By revealing the main lines in the development of child health care, we hoped to achieve a better understanding of the current trends and problems in today's Swedish child health care.Methods:  A selection of official documents about the development of child health care during the period 1930–2000 was studied with the aid of discourse analysis.Results:  Four discourses were identified, which serve as a foundation for a periodization of the development of child health care. In the first period the main task of child health care, alongside checking on the development of the child, was to inform and educate the mothers. During the second period health supervision became the crucial task, to identify risks and discover abnormalities and disabilities. The third period focused on the discussion concerning the identification of health‐related and social ‘risk groups’, and the work of child health care was increasingly geared to supervision of the parents’ care of their children. Parents were to be given support so that they could cope with their difficulties by themselves. During the current period child health care is increasingly expected to direct its work towards the child's surroundings and the family as a whole and is now explicitly defined as an institution that should strengthen parents’ self‐esteem and competence. The level of responsibility for the child's health changed gradually during the different periods, from public responsibility to parental responsibility. The focus of efforts in child health care was changed from being general in the first and second periods to general and selective in period three, and then gradually becoming selective again in period four. While control of the child's physical health was central during the first two periods, psychosocial health came into focus in the last two, along with the importance of supporting the parents to enable them to handle their difficulties by themselves.Concluding remarks:  We noted that it was difficult to translate policy recommendations into practice. One reason was the shifting focus in child health care from the child's physical health to psychosocial problems which in itself meant a shift from descriptions of concrete and well‐defined duties to more abstract and general descriptions of tasks which are by definition open to interpretation. Another reason for the noted difficulty was the transition from unambiguously described measures in terms of paternalistic regulation to more participatory and at the same time more expansive definitions of roles and responsibilities.
Agricultural reforms in Central and Eastern Europe and the former Soviet Union Status and perspectives⋆
Authors: Csaki C. 
Published: August 2005

AbstractThe current status of the agricultural sector in Central and Eastern Europe and the former Soviet Union is described, in the context of reforms undertaken during the transition from a centrally planned economy to a market‐based one. Sectoral performance is analyzed, focussing especially on general trends in production, and emerging trading patterns. Five critical basic elements of reform are described, and a table is presented rating each country in the study on progress in completing each type of reform. Overall conclusions are presented, indicating that in each basic element of reform, the CEE countries have achieved considerably more success than those of the CIS. The paper concludes with a discussion of prospects for development in the region.
The external costs of pasture weed spread: an economic assessment of serrated tussock control
Authors: Jones R. E. , Vere D.T. , Campbell M.H. 
Published: August 2005

AbstractThe external cost associated with the spread of pasture weeds such as serrated tussock (Nassella trichotoma) is an important economic problem. This problem is complicated in many parts of south‐eastern Australia where low rainfall and low soil fertility prevent the economic viability of control of this weed through pasture improvement. A consequence of serrated tussock spread in this region has been calls for increased public intervention in its control. However, because there have been no attempts to measure the external costs of serrated tussock spread, one of the major economic grounds on which this activity might be justified has not been quantified. The purpose of this paper is to provide this information. A stochastic simulation model is developed to determine the size of the external cost associated with the spread of serrated tussock and to evaluate the economic benefits of a range of control scenarios. It is concluded that on low rainfall‐low soil fertility country the socially optimal control option for serrated tussock is to retire land from agriculture and re‐vegetate it with trees.
Allocation of time for meal preparation in a transition economy
Authors: Florkowski Wojciech J. , Moon Wanki , Resurrection Anna V.A. , Jordanov Jordan , Paraskova Pavlina , Beuchat Larry R. , Murgov Kolyo , Chinnan Manjeet S. 
Published: August 2005

AbstractThe decision of how much time to allocate to meal preparation is an endogenous variable to be determined by the opportunity cost of time, preference between market and nonmarket goods and leisure, and household production technology. Using consumer survey data collected in Bulgaria in 1997, this study measured the effect of household income on the amount of time allocated to meal preparation after controlling the effects of demographic, socio‐economic and other characteristics of households. We used the first‐hurdle dominance model to distinguish non‐meal preparers from meal preparers. Since the overall pattern of allocating time between market work, household activity and leisure in a particular country is likely to be conditional on the stage of its economic development, this study presents a unique opportunity to assess the rationality of the time allocation behavior of consumers in an economy in transition from a centrally‐planned to a market‐oriented system. Results showed that household income did not influence the decision of how much time to allocate to meal preparation. While the insignificant linkage between income and time allocation to meal preparation could be due to the differences in preference and household production technology. It can be also attributed to the legacy of four decades of a central‐planning system and underdeveloped food manufacturing and service industries. ©2000 Elsevier Science B.V. All rights reserved.
Impacts of WTO restrictions on subsidized EU sugar exports
Authors: Poonyth Daneswar , Westhoff Patrick , Womack Abner , Adams Gary 
Published: August 2005

AbstractThe study evaluates the impact of World Trade Organization (WTO) restrictions on the European Union (EU) sugar sector and the world sugar market. A small reduction in production quotas would be sufficient to satisfy the export subsidy limitations of the Uruguay Round agreement. Complete elimination of export subsidies by 2005 would require either a 10% reduction in production quotas or the combination of an 8% reduction in quotas and an 11% reduction in intervention prices. Higher world prices resulting from reduced EU exports would result in increased production of unsubsidized C‐sugar, with different impacts across EU member countries explained by differences in institutional pricing arrangements and marginal production costs.
Animal disease incidence and indemnity eradication programs⋆
Authors: Kuchler Fred , Hamm Shannon 
Published: August 2005

AbstractThere are many options for controlling the spread of animal diseases. Some diseases have been treated as public sector problems and many nations have tried to control disease spread by purchasing sick animals from farmers. Government agencies have purchased breeding stock that might transmit diseases. Government agencies have purchased animals that might otherwise have gone to the slaughterhouse, thereby keeping pathogens out of the food supply. Our hypothesis is that when it is not immediately obvious to farmers or private sector buyers which animals carry or transmit diseases, a government indemnity program's success is not assured. Instead, disease control depends on farmers' ability to respond to the relative prices they face. We examine the incentives created by prices (indemnity payment levels) government agencies choose. The scrapie indemnity eradication program in the United States (1952–1992) provides a natural laboratory for measuring the responsiveness to government‐set prices. We show that government‐set prices played a major role in determining the program's outcome: the supply of infected animals was price elastic. We argue that short‐run movements in relative prices and the number of infected animals offer a practical method for assessing program effectiveness.
Estimating labor supply of farm households under nonseparability: empirical evidence from Nepal
Authors: Abdulai Awudu , Regmi Punya Prasad 
Published: August 2005

AbstractThis paper examines the labor supply of farm households in Nepal using a recently developed methodology that accounts for the simultaneity between production and consumption decisions of the households. Estimates of marginal products of male and female labor or shadow wages are obtained from an agricultural production function. An instrumental variable approach is then used to recover the household's structural labor supply from variations in the shadow wages and income, as well as other household characteristics. The findings reveal that both male and female total labor supply are sensitive to changes in shadow wages and income. Human capital embodied in education is found to exert a significant positive effect on output, but has no statistically significant impact on total labor supply of individuals. The results also rejects the existence of efficient labor markets in rural Nepal.