3,367 research outputs found
Nurses\u27 Narratives of unforgettable patient care events
Purpose: To explore the experience of registered nurses (RNs) caring for patients in contemporary hospitals. Design: The descriptive phenomenological study was based in the philosophical perspectives of Husserl and Merleau-Ponty. Methods: A purposive sample of 46 RNs employed in acute care hospitals in the southeastern United States (US) were recruited by network sampling. Data from unstructured interviews were analyzed in an interpretive group and themes were identified. Findings: Four themes were identified: (a) extraordinary caregiving events, (b) incomprehensibility, (c) questioning whether anything else could have been done, and (d) “alone or together,” indicating the isolation nurses often experience while giving care as well as profound moments of connection, especially with patients. Conclusions: Caregiving experiences resulted in an accumulating residue of moral distress which in turn became ground for future experiences in the everyday work life of RNs. Sometimes years later, participants were still trying to justify and understand the outcomes and perhaps to absolve themselves from blame. Participants were confronted with the limits of science and skill and plunged into the realm of existential questions for which they had no ready answers
Common aetiology for diverse language skills in 41/2-year-old twins
Multivariate genetic analysis was used to examine the genetic and environmental aetiology of the interrelationships of diverse linguistic skills. This study used data from a large sample of 4 1/2 year-old twins who were tested on measures assessing articulation, phonology, grammar, vocabulary, and verbal memory. Phenotypic analysis suggested two latent factors: articulation (2 measures) and general language (the remaining 7), and a genetic model incorporating these factors provided a good fit to the data. Almost all genetic and shared environmental influences on the 9 measures acted through the two latent factors. There was also substantial aetiological overlap between the two latent factors, with a genetic correlation of 0·64 and shared environment correlation of 1·00. We conclude that to a large extent, the same genetic and environmental factors underlie the development of individual differences in a wide range of linguistic skills
Tripartite ATP-Independent Periplasmic (TRAP) Transporters and Tripartite Tricarboxylate Transporters (TTT): From Uptake to Pathogenicity
The ability to efficiently scavenge nutrients in the host is essential for the viability of any pathogen. All catabolic pathways must begin with the transport of substrate from the environment through the cytoplasmic membrane, a role executed by membrane transporters. Although several classes of cytoplasmic membrane transporters are described, high-affinity uptake of substrates occurs through Solute Binding-Protein (SBP) dependent systems. Three families of SBP dependant transporters are known; the primary ATP-binding cassette (ABC) transporters, and the secondary Tripartite ATP-independent periplasmic (TRAP) transporters and Tripartite Tricarboxylate Transporters (TTT). Far less well understood than the ABC family, the TRAP transporters are found to be abundant among bacteria from marine environments, and the TTT transporters are the most abundant family of proteins in many species of β-proteobacteria. In this review, recent knowledge about these families is covered, with emphasis on their physiological and structural mechanisms, relating to several examples of relevant uptake systems in pathogenicity and colonization, using the SiaPQM sialic acid uptake system from Haemophilus influenzae and the TctCBA citrate uptake system of Salmonella typhimurium as the prototypes for the TRAP and TTT transporters, respectively. High-throughput analysis of SBPs has recently expanded considerably the range of putative substrates known for TRAP transporters, while the repertoire for the TTT family has yet to be fully explored but both types of systems most commonly transport carboxylates. Specialized spectroscopic techniques and site-directed mutagenesis have enriched our knowledge of the way TRAP binding proteins capture their substrate, while structural comparisons show conserved regions for substrate coordination in both families. Genomic and protein sequence analyses show TTT SBP genes are strikingly overrepresented in some bacteria, especially in the β-proteobacteria and some α-proteobacteria. The reasons for this are not clear but might be related to a role for these proteins in signaling rather than transport
Massive over-representation of solute-binding proteins (SBPs) from the tripartite tricarboxylate transporter (TTT) family in the genome of the α-proteobacterium Rhodoplanes sp. Z2-YC6860.
Lineage-specific expansion (LSE) of protein families is a widespread phenomenon in many eukaryotic genomes, but is generally more limited in bacterial genomes. Here, we report the presence of 434 genes encoding solute-binding proteins (SBPs) from the tripartite tricarboxylate transporter (TTT) family, within the 8.2 Mb genome of the α-proteobacterium Rhodoplanes sp. Z2-YC6860, a gene family over-representation of unprecedented abundance in prokaryotes. Representing over 6 % of the total number of coding sequences, the SBP genes are distributed across the whole genome but are found rarely in low-GC islands, where the gene density for this family is much lower. This observation, and the much higher sequence identity between the 434 Rhodoplanes TTT SBPs compared with the average identity between homologues from different species, is indicative of a key role for LSE in the expansion. The TTT SBP genes were found in the vicinity of genes encoding membrane components of transport systems from different families, as well as regulatory proteins such as histidine-kinases and transcription factors, indicating a broad range of functions around the sensing, response and transport of organic compounds. A smaller expansion of TTT SBPs is known in some species of the β-proteobacteria Bordetella and we observed similar expansions in other β-proteobacterial lineages, including members of the genus Comamonas and the industrial biotechnology organism Cupriavidus necator, indicating that strong environmental selection can drive SBP duplication and specialisation from multiple evolutionary starting points
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Scale-invariant moving finite elements for nonlinear partial differential equations in two dimensions
A scale-invariant moving finite element method is proposed for the adaptive solution of nonlinear partial differential equations. The mesh movement is based on a finite element discretisation of a scale-invariant conservation principle incorporating a monitor function, while the time discretisation of the resulting system of ordinary differential equations is carried out using a scale-invariant time-stepping which yields uniform local accuracy in time.
The accuracy and reliability of the algorithm are successfully tested against exact self-similar solutions where available, and otherwise against a state-of-the-art h-refinement scheme for solutions of a two-dimensional porous medium equation problem with a moving boundary. The monitor functions used are the dependent variable and a monitor related to the surface area of the solution manifold
Asymptotics of the Farey Fraction Spin Chain Free Energy at the Critical Point
We consider the Farey fraction spin chain in an external field . Using
ideas from dynamical systems and functional analysis, we show that the free
energy in the vicinity of the second-order phase transition is given,
exactly, by
Here is a reduced
temperature, so that the deviation from the critical point is scaled by the
Lyapunov exponent of the Gauss map, . It follows that
determines the amplitude of both the specific heat and susceptibility
singularities. To our knowledge, there is only one other microscopically
defined interacting model for which the free energy near a phase transition is
known as a function of two variables.
Our results confirm what was found previously with a cluster approximation,
and show that a clustering mechanism is in fact responsible for the transition.
However, the results disagree in part with a renormalisation group treatment
A mixed methods study of knee confidence and self-efficacy: perceptions of knee osteoarthritis patients from the good life with osteoarthritis in Denmark initiative
Purpose: The Good Life with osteoArthritis in Denmark (GLA:D) Initiative is an evidence-based treatment programme for patients with knee and hip osteoarthritis (OA). It incorporates training physiotherapists to deliver care in accordance with the clinical guidelines by educating patients on their condition and by delivering supervised neuromuscular exercises to relieve pain and improve function. The importance of self-efficacy, and confidence in exercise, to exercise adherence has not been reported for the GLA:D population. In addition, worse knee confidence in people with knee OA is associated with higher pain and greater perceived knee instability. The aims of this study were to investigate the association between knee confidence and self-efficacy in patients with knee OA in the GLA:D registry; and to explore patients’ perception of their experiences with the GLA:D programme, and whether confidence and self-efficacy has a role to play in continuing with the GLA:D exercises in the long-term.
Methods: This study used a mixed methods design. Patients with knee OA who were offered at least two educational sessions and six weeks of GLA:D exercise programme between January–March 2015 were identified from the GLA:D registry (n = 484) and sent an online survey. Ordinal regression analyses were performed. Knee confidence, assessed using the Knee injury and Osteoarthritis Outcomes Score (KOOS; quality of life subscale, question 3), was the dependent variable and self-reported measures for exercise self-efficacy; arthritis self-efficacy; multidimensional outcomes expectations for exercise; and KOOS pain and activities of daily living (ADL) were the independent variables. Knee confidence score ranged from 0–4 with 0 indicating higher knee confidence. The independent variables ranged from 0–10 or 0–100 with 0 indicating worse symptoms or confidence. Subsequently, semi-structured interviews (n = 4) were used to explore patients’ perceived confidence and adherence to the GLA:D exercises. Interviews were transcribed verbatim, and analysed using interpretative phenomenological analysis.
Results: 200 patients (41.3%) responded to the survey. At 7–10 months following treatment initiation, 9.5% of patients were not at all troubled by lack of knee confidence; 39.5% were mildly troubled; 31.5% were moderately troubled; 15.5% were severely troubled; and 4% were extremely troubled. Patients with higher arthritis self-efficacy score were more likely to have higher knee confidence (odds ratio [OR] = 0.76; 95% confidence interval [CI] 0.63, 0.93; P = 0.007). Patients with higher KOOS ADL score were more likely to have higher knee confidence, although this association was small (OR = 0.96; 95% CI 0.93, 0.99; P = 0.006). No association was found between knee confidence and exercise self-efficacy (OR = 1.00; 95% CI 0.99, 1.01; P = 0.90). Patients reflected on seeing great improvements in their confidence, pain and mobility with the programme. They felt their symptoms got worse if they did not keep up with the exercises. Patients reflected on the importance of continued contact with their physiotherapist after the 6-week programme for further motivation and reassurance. One of the barriers that discouraged patients from continuing with the exercises in the long-term was the cost for additional GLA:D exercise classes with their physiotherapist.
Conclusions: Patients are troubled by the lack of knee confidence after the GLA:D exercise programme; they reflected this was due to their negative experiences prior to entering the GLA:D programme. Arthritis self-efficacy and KOOS ADL were significantly associated with knee confidence, but no association was found with exercise self-efficacy. Patients from the interview reflected that maintaining contact with their physiotherapist was an important factor to motivate them to continue exercising
Environmental control on the structure of echinoid assemblages in the Bellingshausen Sea (Antarctica)
The Bellingshausen Sea is one of the most remote and least surveyed seas of the Southern Ocean, so that little was known about benthic communities and those factors that determine community structuring until recently. The present work aims at characterizing the structure and spatial distribution of echinoid assemblages in the Bellingshausen Sea, as well as identifying the environmental factors that determine assemblage structuring. Echinoids were collected at 32 stations using an Agassiz trawl, at depths of 86–3,304 m, during BENTART oceanographic expeditions led in 2003 and 2006. Sediment and bottom water properties were analysed using an USNEL-type box corer and a Neil Brown Instrument System Mark III CTD, respectively. Echinoids were found at all stations, except Peter I Island. Seventeen species were identified, representing 22 % of the echinoid species present in the Southern Ocean and increasing twofold the number of species recorded in the Bellingshausen Sea so far. The echinoid fauna is dominated by the very abundant species Sterechinus antarcticus. Depth is the key factor that determines the nature of echinoid assemblages, which are mainly divided into the continental shelf, the slope and the deep-sea basin. In addition, sediment properties, namely redox values, organic matter and mud content, best match species dispersion on the shelf. Sediment properties affect echinoid distribution depending on species food range and feeding strategy. As it might be expected, sediment properties more strongly influence specialist feeders (Schizasteridae and Cidaridae) than generalists (Echinidae).Versión del edito
Prospectus, January 22, 2003
https://spark.parkland.edu/prospectus_2003/1000/thumbnail.jp
Universal Extra Dimensions and the Higgs Boson Mass
We study the combined constraints on the compactification scale 1/R and the
Higgs mass m_H in the standard model with one or two universal extra
dimensions. Focusing on precision measurements and employing the
Peskin-Takeuchi S and T parameters, we analyze the allowed region in the (m_H,
1/R) parameter space consistent with current experiments. For this purpose, we
calculate complete one-loop KK mode contributions to S, T, and U, and also
estimate the contributions from physics above the cutoff of the
higher-dimensional standard model. A compactification scale 1/R as low as 250
GeV and significantly extended regions of m_H are found to be consistent with
current precision data.Comment: 21 pages, Latex, 6 eps figures, an error in calculations was
corrected and results of analysis changed accordingly, references adde
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