1,879 research outputs found

    Pseudoscalar Vertex, Goldstone Boson and Quark Masses on the Lattice

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    We analyse the Structure Function collaboration data on the quark pseudoscalar vertex and extract the Goldstone boson pole contribution, in 1/p2. The strength of the pole is found to be quite large at presently accessible scales. We draw the important consequences of this finding for the various definitions of quark masses, and point out potential problems with the operator product expansion.Comment: 13 pages, 6 eps figures, LaTeX. Minor modifications to the text, and corrections to Fig.

    Living with chronic kidney disease : Perceptions of illness and health-related quality of life

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    This thesis comprises two studies concerning illness perceptions and perceived health-related quality of life (HRQoL) in patients with chronic kidney disease (CKD). The overall aim was to evaluate psychometric properties of a Swedish translation of the Revised Illness Perception Questionnaire (IPQ-R) (study I), and furthermore to explore illness perceptions (study I) and HRQoL (study II) in adult patients in different stages of renal insufficiency (CKD stages 2-5). In study I, evidence for construct validity was gathered through cognitive interviews (N=7) and other psychometric assessments (n=54). The results supported construct validity of the IPQ-R in a CKD context. The most supported IPQ-R dimensions were identity, timeline cyclical, consequences and emotional representations. The illness coherence, timeline and controllability dimensions need to be further explored in this patient group. Most IPQ-R dimensions distinguished illness perceptions between groups of different CKD stages and symptom burden. The patients in earlier CKD stages (CKD stages 2-3) or with <8 symptoms did not hold as strong beliefs about their illness being as threatening as those in the advanced stages (CKD stages 4-5) or with ≥8 symptoms. The patients who experienced more symptoms or had more advanced CKD expressed less illness coherence than those experiencing fewer symptoms or in earlier CKD stages. Negative illness perceptions, i.e. experiencing more symptoms and perceiving the illness as more threatening was associated with an impaired HRQoL and also with mainly evasive, fatalistic, emotive and supportant coping styles. A substantial part of the patient responses referred to behavioural and psychological attributions as contributory causes to their CKD. Leg cramps, stiff/sore joints, dry skin and impaired sexual desire/ability were the most commonly reported symptoms in earlier CKD stages. Fatigue, lack of energy, leg cramps and thirst were the most common symptoms in the advanced disease stages. An uncertainty assessing symptoms attributed to CKD was indicated, especially in earlier CKD stages. Study II had a cross-sectional design with 535 patients across different stages of renal insufficiency (CKD stages 2–5) up to initiation of dialysis treatment, and 55 controls assessed for HRQoL through the SF-36 questionnaire together with biomarkers. All HRQoL dimensions deteriorated significantly with impaired kidney function, with the lowest scores in those with kidney failure (CKD 5). The largest differences between the patient groups were seen within physical health. The smallest disparities were seen in bodily pain and mental health. Patients in earlier CKD stages showed significantly decreased HRQoL compared to matched controls. Patients in CKD 5 demonstrated significantly deteriorated scores also in mental health compared to those in CKD 4. Glomerular filtration rate <45 ml/min/1.73 m², age ≥61 years, cardiovascular disease (CVD), diabetes, C-reactive protein (CRP) ≥5 mg/L, haemoglobin ≤110 g/L, p-albumin ≤35 g/L and overweight were associated with impaired HRQoL. CRP and CVD emerged as primary predictors of impaired HRQoL, followed by reduced GFR and diabetes. In renal care, increased understanding of illness perceptions and HRQoL are important assignments, since they interrelate and also have an impact on the patients’ coping and health behaviour. Skilled attention to the patients’ illness perceptions and HRQoL may enable health care providers to identify patients at risk for sub-optimal self-management and/or impaired HRQoL, identify and focus on relevant problems as well as supporting healthy behaviour, self-management and self-care. There is a need to further evaluate effective strategies to enhance illness perceptions and HRQoL in CKD patients such as educational interventions, programmes for improved physical activity and - especially in advanced CKD - proper psychosocial support. The findings also indicate that renal care may benefit from a more comprehensive approach, including increased attention to health promoting interventions regarding risk factors and comorbid conditions

    A new species of abyssal sea anemone and its symbiotic relationship with a scaphopod

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    M.A. University of Kansas, Systematics and Ecology 1996In this thesis I report the results of the first study of a symbiosis between an abyssal sea anemone and a scaphopod. I describe the sea anemone as Benthactis nomadas n. g., n. sp. The sea anemones and scaphopods were collected at a soft-sediment site at 4100 m depth in the northeastern Pacific Ocean. Sea anemones of this species were always attached to a scaphopod shell; thus, I infer that the symbiosis is obligate for the sea anemone. I conclude that the symbiosis is facultative for the scaphopod because 8% of the shells showed no evidence of recent sea anemone attachment. I infer from sea floor photographs and from the fact that these organisms are trawled that the scaphopods carrying these sea anemones live at or near the surface, an atypical habitat for a scaphopod. I hypothesize that this symbiosis is initiated when a planula larva of Benthactis nomadas, n. g., n. sp. lands on the exposed dorsal tip of a scaphopod shell. The results of a biomechanics experiment I conducted support my hypothesis that as the sea anemone grows, the scaphopod adjusts its position in the sediment because remaining near the surface requires less energy than dragging a sea anemone through the sediment. Typically, a scaphopod at the sediment surface would be exposed to pelagic and epibenthic predators; I infer that this scaphopod is protected from its predators by the sea anemone. Under the protective shelter of the anemone, the scaphopod can remain at the sediment surface and forage in upper layers of sediment that contain more energy than deeper layers. The sea anemone also benefits from the symbiosis. It receives an attachment site in an environment where hard substratum is limited, and it may gain increased access to food. Based on the results of experiments that I conducted and on inferences, I propose that the relationship between the sea anemone and the scaphopod is mutualistic

    Jew or Christian: Who Wrote the Book of Revelation?

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    Second Annual Lecture in Jewish-Christian Engagement…Dr. Elaine Pagels, Professor of Religion, Princeton University. Author of: Adam and Eve and the Serpent, Beyond Belief: The Secret Gospel of Thomas, The Gnostic Gospels, and Reading Judas: The Gospel of Judas and the Shaping of Christianity.https://digitalcommons.fairfield.edu/bennettcenter-posters/1265/thumbnail.jp

    Aviation Data Mining

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    We explore different methods of data mining in the field of aviation and their effectiveness. The field of aviation is always searching for new ways to improve safety. However, due to the large amounts of aviation data collected daily, parsing through it all by hand would be impossible. Because of this, problems are often found by investigating accidents. With the relatively new field of data mining we are able to parse through an otherwise unmanageable amount of data to find patterns and anomalies that indicate potential incidents before they happen. The data mining methods outlined in this paper include Multiple Kernel Learning algorithms, Hidden Markov Models, Hidden Semi-Markov Models, and Natural Language Processing

    A Nonperturbative Calculation of Basic Chiral QCD Parameters Within Zero Modes Enhancement Model of the QCD Vacuum. I

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    A new zero modes enhancement (ZME) model of the true QCD vacuum is breifly described. It makes possible to analytically investigate and calculate numerically low-energy QCD structure from first principles. Expressions of basic chiral QCD parameters (the pion decay constant, the quark and gluon condensates, the dynamically generated quark mass, etc) as well as the vacuum energy density (up to the sign, by definition, the bag constant), suitable for numerical calculations, have been derived. Solution to the Schwinger-Dyson (SD) equation for the quark propagator in the infrared (IR) domain on the basis of the ZME effect in QCD was used for this purpose. There are only two independent quantities (free parameters) by means of which calculations must be done within our approach. The first one is the integration constant of the above mentioned quark SD equation of motion. The second one is a scale at which nonperturbative effects begin to play a dominant role.Comment: 17 pages, two figures added, minor change
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