21 research outputs found

    Single photon double ionization of Helium at 800 eV - observation of the Quasi Free Mechanism

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    In a kinematically complete experiment we have measured the photo double ionization of Helium at aphoton energy of 800 eV and observed He2+ ions with 0 momentum, corresponding to a back-to-back-emissionof the two electrons. The results are in good agreement with theoretical calculations

    Ejection of quasi-free electron pairs from the helium atom ground state by single photon absorption

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    We investigate single photon double ionization (PDI) of helium at photon energies of 440 and 800 eV. We observe doubly charged ions with close to zero momentum corresponding to electrons emitted back-to-back with equal energy. These slow ions are the unique fingerprint of an elusive quasi-free PDI mechanism predicted by Amusia et al. nearly four decades years ago [J. Phys. B 8, 1248, (1975)] . It results from the non-dipole part of the electromagnetic interaction. Our experimental data are in excellent agreement with calculations performed using the convergent close coupling and time dependent close coupling methods

    Visual impairment is associated with physical and mental comorbidities in older adults:a cross-sectional study

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    Background<p></p> Visual impairment is common in older people and the presence of additional health conditions can compromise health and rehabilitation outcomes. A small number of studies have suggested that comorbities are common in visual impairment; however, those studies have relied on self-report and have assessed a relatively limited number of comorbid conditions.<p></p> Methods<p></p> We conducted a cross-sectional analysis of a dataset of 291,169 registered patients (65-years-old and over) within 314 primary care practices in Scotland, UK. Visual impairment was identified using Read Code ever recorded for blindness and/or low vision (within electronic medical records). Prevalence, odds ratios (from prevalence rates standardised by stratifying individuals by age groups (65 to 69 years; 70 to 74; 75 to 79; 80 to 84; and 85 and over), gender and deprivation quintiles) and 95% confidence intervals (95% CI) of 37 individual chronic physical/mental health conditions and total number of conditions were calculated and compared for those with visual impairment to those without.<p></p> Results<p></p> Twenty seven of the 29 physical health conditions and all eight mental health conditions were significantly more likely to be recorded for individuals with visual impairment compared to individuals without visual impairment, after standardising for age, gender and social deprivation. Individuals with visual impairment were also significantly more likely to have more comorbidities (for example, five or more conditions (odds ratio (OR) 2.05 95% CI 1.94 to 2.18)).<p></p> Conclusions<p></p> Patients aged 65 years and older with visual impairment have a broad range of physical and mental health comorbidities compared to those of the same age without visual impairment, and are more likely to have multiple comorbidities. This has important implications for clinical practice and for the future design of integrated services to meet the complex needs of patients with visual impairment, for example, embedding depression and hearing screening within eye care services

    Comprehensive Geriatric Assessment (CGA) in general practice: Results from a pilot study in Vorarlberg, Austria

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    <p>Abstract</p> <p>Background</p> <p>Most comprehensive geriatric assessment (CGA) programs refer to hospital-based settings. However the body of geriatric healthcare is provided by general practitioners in their office. Structured geriatric problem detection by means of assessment instruments is crucial for efficient geriatric care giving in the community.</p> <p>Methods</p> <p>We developed and pilot tested a German language geriatric assessment instrument adapted for general practice. Nine general practices in a rural region of Austria participated in this cross-sectional study and consecutively enrolled 115 persons aged over 75 years. The prevalence of specific geriatric problems was assessed, as well as the frequency of initiated procedures following positive and negative tests. Whether findings were new to the physician was studied exemplarily for the items visual and hearing impairment and depression. The acceptability was recorded by means of self-administered questionnaires.</p> <p>Results</p> <p>On average, each patient reported 6.4 of 14 possible geriatric problems and further consequences resulted in 43.7% (27.5% to 59.8%) of each problem.</p> <p>The items with either the highest prevalence and/or the highest number of initiated actions by the GPs were osteoporosis risk, urinary incontinence, decreased hearing acuity, missing pneumococcal vaccination and fall risk. Visual impairment was newly detected in only 18% whereas hearing impairment and depression was new to the physician in 74.1% and 76.5%, respectively.</p> <p>A substantial number of interventions were initiated not only following positive tests (43.7% per item; 95% CI 27.5% to 59.8%), but also as a consequence of negative test results (11.3% per item; 95% CI 1.7% to 20.9%).</p> <p>The mean time expenditure to accomplish the assessment was 31 minutes (SD 10 min). Patients (89%) and all physicians confirmed the CGA to provide new information in general on the patient's health status. All physicians judged the CGA to be feasible in everyday practice.</p> <p>Conclusion</p> <p>This adapted CGA was feasible and well accepted in the general practice sample. High frequencies of geriatric problems were detected prompting high numbers of problem-solving initiatives. But a substantial number of actions of the physicians following negative tests point to the risks of too aggressive treatment of elderly patients with possibly subsequent negative effects.</p
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