399 research outputs found
Confining potential in momentum space
A method is presented for the solution in momentum space of the bound state problem with a linear potential in r space. The potential is unbounded at large r leading to a singularity at small q. The singularity is integrable, when regulated by exponentially screening the r-space potential, and is removed by a subtraction technique. The limit of zero screening is taken analytically, and the numerical solution of the subtracted integral equation gives eigenvalues and wave functions in good agreement with position space calculations
Solution of two-body relativistic bound state equations with confining plus Coulomb interactions
Studies of meson spectroscopy have often employed a nonrelativistic Coulomb plus Linear Confining potential in position space. However, because the quarks in mesons move at an appreciable fraction of the speed of light, it is necessary to use a relativistic treatment of the bound state problem. Such a treatment is most easily carried out in momentum space. However, the position space Linear and Coulomb potentials lead to singular kernels in momentum space. Using a subtraction procedure we show how to remove these singularities exactly and thereby solve the Schroedinger equation in momentum space for all partial waves. Furthermore, we generalize the Linear and Coulomb potentials to relativistic kernels in four dimensional momentum space. Again we use a subtraction procedure to remove the relativistic singularities exactly for all partial waves. This enables us to solve three dimensional reductions of the Bethe-Salpeter equation. We solve six such equations for Coulomb plus Confining interactions for all partial waves
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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
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
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
Stochastic Variational Search for H
A four-body calculation of the bound state, $^{\
4}_{\Lambda\Lambda}NN\Lambda N\Lambda\Lambda\Lambda\Lambda_\Lambda^3{H}+\Lambda\Lambda\LambdaB_{\Lambda\Lambda}(^{6}_{\Lambda\Lambda}{He})d\Lambda\Lambda$ model in the Letter.Comment: Corrected typos, added addtional calculations regarding a truncated
to l=0 interaction model, 4 pages, 3 figure
Control Management and Business Performances: the Malaysian Family SMEs Perspectives
This study examined the relationship between control management and family business performance in the Malaysian context. It has two objectives, the first being to determine the relationship of organizational credit control policy and procedures, employee development and motivation, and intelligence collection systems to subsequent collection reports in Malaysian family SMEs. The second objective is to investigate the moderating effect of participation in decision-making and work effort towards innovation and business performance. This is a descriptive study involving 90 senior executives employed in 90 Malaysian family SMEs/firms. A correlation analysis from this study confirmed previous researchers’ observations that high-level organizational commitment to credit control management is linked to improvements in business performance. The results suggest that three components – credit policy, employee development, and intelligence collection systems – are the most important predictors for the efficiency and effectiveness of credit control management.  
A woman with cystic fibrosis, severe hypoxaemia, an atrial thrombus and a patent foramen ovale: a case report
<p>Abstract</p> <p>Introduction</p> <p>Cystic fibrosis is usually associated with chronic pulmonary sepsis and frequent infective exacerbations. We report a very unusual cause of severe hypoxaemia in a woman with cystic fibrosis caused by thrombus formation in the right atrium.</p> <p>Case presentation</p> <p>A 21-year-old Caucasian woman with cystic fibrosis and a totally implantable venous access device presented with severe hypoxaemia. This was initially treated with antibiotics but her oxygen levels did not improve significantly. Subsequently, a transient ischaemic attack occurred. Further investigations, including a contrast echocardiogram and a cardiac magnetic resonance scan, revealed the presence of a large right atrial thrombus and right-to-left intracardiac shunt through a patent foramen ovale.</p> <p>Conclusion</p> <p>This case highlights the need to consider a right-to-left shunt in chronic respiratory diseases when hypoxaemia is out of proportion to the degree of lung function impairment. Totally implantable venous access devices should always be considered as a source of thrombus formation.</p
Osteopontin as potential biomarker and therapeutic target in gastric and liver cancers
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