747 research outputs found
Kaon-nucleus scattering
Two kinds of number density distributions of the nucleus, harmonic well and Woods-Saxon models, are used with the t-matrix that is taken from the scattering experiments to find a simple optical potential. The parameterized two body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to imaginary part of the forward elastic scattering amplitude, are shown. The eikonal approximation was chosen as the solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering
Elastic Differential Cross Sections for Space Radiation Applications
The eikonal, partial wave (PW) Lippmann-Schwinger, and three-dimensional
Lippmann- Schwinger (LS3D) methods are compared for nuclear reactions that are
relevant for space radiation applications. Numerical convergence of the eikonal
method is readily achieved when exact formulas of the optical potential are
used for light nuclei (A 16), and the momentum-space representation of
the optical potential is used for heavier nuclei. The PW solution method is
known to be numerically unstable for systems that require a large number of
partial waves, and, as a result, the LS3D method is employed. The effect of
relativistic kinematics is studied with the PW and LS3D methods and is compared
to eikonal results. It is recommended that the LS3D method be used for high
energy nucleon-nucleus reactions and nucleus-nucleus reactions at all energies
because of its rapid numerical convergence and stability
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Communication and cognitive impairments and healthcare decision-making in MND: A narrative review
Rationale: Motor neurone disease (MND) is a neurodegenerative disease presenting with progressive weakness of voluntary muscles. For any condition, person-centred healthcare relies on the sharing of information and a mutual understanding of the person’s needs and preferences. Decision-making in MND becomes more complex as there is no cure and a high prevalence of co-morbid communication and/or cognitive difficulties.
Objective: To identify the reported impact of communication and/or cognitive impairment on patient and carer involvement in healthcare decision-making in MND.
Methods: A review and synthesis of studies addressing issues of communication impairment and/or cognitive impairment in relation to decision-making focussed on MND was conducted. Articles were excluded if they were reviews, case studies, conference papers or commentaries. To be included studies needed to address issues of communication impairment or cognitive impairment specifically in relation to decision-making. Relevant data was extracted verbatim and subjected to content analysis to support the narrative summary.
Results: Seventy-six articles were identified and 35 articles screened. Six articles met inclusion criteria each describing examples of decision-making in MND. There was limited data related to communication and/or cognitive impairment and the impact these impairments may have on decision-making despite recognition that many people with MND may lose verbal communication or develop subtle cognitive impairments. The literature is primarily from the perspective of others.
Conclusion: This review highlights that the current body of literature exploring decision-making within the MND population presents us with extremely limited insights into the impact of communication and/or cognitive impairments on healthcare decision-making. Extant literature focuses on interventions (namely ventilation and gastrostomy), the broad process of decision-making, or cognitive assessment of decision-making ability. Whilst most studies acknowledge that deficits in communication or cognition impact the decision-making process, this issue is not the focus of any study
Eikonal solutions to optical model coupled-channel equations
Methods of solution are presented for the Eikonal form of the nucleus-nucleus coupled-channel scattering amplitudes. Analytic solutions are obtained for the second-order optical potential for elastic scattering. A numerical comparison is made between the first and second order optical model solutions for elastic and inelastic scattering of H-1 and He-4 on C-12. The effects of bound-state excitations on total and reaction cross sections are also estimated
Scattering calculations and confining interactions
Most of the research work performed under this grant were concerned with strong interaction processes ranging from kaon-nucleon interaction to proton-nucleus scattering calculations. Research performed under this grant can be categorized into three groups: (1) parametrization of fundamental interactions, (2) development of formal theory, and (3) calculations based upon the first two. Parametrizations of certain fundamental interactions, such as kaon-nucleon interaction, for example, were necessary because kaon-nucleon scattering amplitude was needed to perform kaon-nucleus scattering calculations. It was possible to calculate kaon-nucleon amplitudes from the first principle, but it was unnecessary for the purpose of the project. Similar work was also done for example for anti-protons and anti-nuclei. Formal developments to some extent were also pursued so that consistent calculations can be done
Temocillin in the treatment of Burkholderia cepacia infection in cystic fibrosis
AbstractBackgroundInfections due to Burkholderia cepacia complex (Bcc) strains increase morbidity and mortality in cystic fibrosis (CF). Some transplant centres reject Bcc infected patients. We reviewed the results in patients treated with i.v temocillin.MethodsTwenty-three patients who received 38 courses of temocillin (1988–1998) were identified from the CF database at Royal Brompton Hospital. In three patients' data were inadequate; therefore analysis was done in 20. Outcome was measured as improvement, deterioration or no change (compared to admission) in the following categories: clinical (temperature, dyspnoea, sputum volume, chest pain), physiological (FEV1, FVC, oxygen saturation) and inflammatory markers (WBC, ESR, CRP). Patients who improved in two categories were classified as having improved. Antibiotic sensitivities and outcome were recorded.ResultsIn 18 of 32 courses (56.25%) improvement occurred. The organism (Bcc) in eight patients' sputum became resistant (three died). The antibiotics was changed in five patients with Bcc strains sensitive to temocillin because of no improvement and one patient due to allergy (rash). The average time to the next i.v antibiotic was 41 days. Eight patients died (in three the Bcc strain was resistant to temocillin). Fourteen patients with Bcc were transplanted and eight patients survived. Another patient who developed Bcc infection post-operatively, failing to respond to temocillin.ConclusionsThese results suggest the potential benefit of i.v temocillin in CF patients with Bcc for exacerbations and at the time of transplantation
Relativistic Three-Dimensional Lippman-Schwinger Cross Sections for Space Radiation Applications
Radiation transport codes require accurate nuclear cross sections to compute particle fluences inside shielding materials. The Tripathi semi-empirical reaction cross section, which includes over 60 parameters tuned to nucleon-nucleus (NA) and nucleus-nucleus (AA) data, has been used in many of the world’s best-known transport codes. Although this parameterization fits well to reaction cross section data, the predictive capability of any parameterization is questionable when it is used beyond the range of the data to which it was tuned. Using uncertainty analysis, it is shown that a relativistic three-dimensional Lippmann-Schwinger (LS3D) equation model based on Multiple Scattering Theory (MST) that uses 5 parameterizations—3 fundamental parameterizations to nucleon-nucleon (NN) data and 2 nuclear charge density parameterizations—predicts NA and AA reaction cross sections as well as the Tripathi cross section parameterization for reactions in which the kinetic energy of the projectile in the laboratory frame (TLab) is greater than 220 MeV/n. The relativistic LS3D model has the additional advantage of being able to predict highly accurate total and elastic cross sections. Consequently, it is recommended that the relativistic LS3D model be used for space radiation applications in which TLab \u3e 220MeV/n
Clinical importance of cystic fibrosis-related diabetes
AbstractThe prevalence of cystic fibrosis-related diabetes (CFRD) and glucose intolerance (IGT) has risen dramatically over the past 20 years as survival has increased for people with cystic fibrosis (CF). Diabetes is primarily caused by pancreatic damage, which reduces insulin secretion, but glucose tolerance is also modified by factors that alter insulin resistance, such as intercurrent illness and infection. CFRD not only causes the symptoms and micro and macrovascular complications seen in type 1 and type 2 diabetes in the general population, but also is associated with accelerated pulmonary decline and increased mortality. Pulmonary effects are seen some years before the diagnosis of CFRD, implying that impaired glucose tolerance may be detrimental.Current practice is to screen for changes in glucose tolerance by regular measurement of fasting blood glucose, by oral glucose tolerance test or a combination of these approaches with symptom review and measurement of HbA1C. Treatment is clearly indicated for those with CFRD and fasting hyperglycaemia to control symptoms and reduce complications. As nutrition is critical in people with CF to maintain body mass and lung function, blood glucose should be controlled in CFRD by adjusting insulin doses to the requirements of adequate food intake and not by calorie restriction. It is less clear whether blood glucose control will have clinical benefits in the management of patients with CFRD without fasting hyperglycaemia or with impaired glucose tolerance and further studies are required to establish the best treatment for this patient group
Hyperonic mixing in five-baryon double-strangeness hypernuclei in a two-channel treatment
Properties of hypernuclei H and He are studied in a two-channel approach with explicit treatment of
coupling of channels ^3\text{Z}+\Lambda+\Lambda and \alpha+\Xi. Diagonal
\Lambda\Lambda and coupling \Lambda\Lambda-\Xi N interactions are derived
within G-matrix procedure from Nijmegen meson-exchange models. Bond energy
\Delta B_{\Lambda\Lambda} in He exceeds significantly
that in H due to the channel coupling. Diagonal \Xi\alpha
attraction amplifies the effect, which is sensitive also to \Lambda-core
interaction. The difference of the \Delta B_{\Lambda\Lambda} values can be an
unambiguous signature of the \Lambda\Lambda-\Xi N coupling in \Lambda\Lambda
hypernuclei. However, improved knowledge of the hyperon-nucleus potentials is
needed for quantitative extraction of the coupling strength from future data on
the \Lambda\Lambda hypernuclear binding energies.Comment: 11 pages with 3 figures; Phys. Rev. C, accepte
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