The prevalence of concern about weight loss and decline in food intake in people with advanced cancer

Aim: This paper reports findings of a survey of the prevalence of concern about weight loss and decline in food intake in patients with advanced cancer. It was part of a larger study with the purpose of exploring the potential for helping patients and their families live with the symptoms. Background: Weight loss and anorexia are commonly reported symptoms in people with advanced cancer. Little is known about patient experience of the symptoms, in particular whether they find them of concern. If patients are troubled by the symptoms, mitigating this distress may be important in enabling them to die at home. Methods: The research was a case study design. The cases were two community palliative home care teams serving a population of over 1 million people in the South of England in 2003. Multiple methods of data collection included a questionnaire survey and semi-structured conversational style interviews with a purposive sample of patients (n = 30), carers (n = 23) and nurse specialists (n = 14). The survey was of 233 patients with advanced cancer (response rate 85%). These people represented 67% of the total caseload across the two study sites over a two week period. Analyses of the survey data were conducted using SPSS (Statistical Package for Social Scientists version 12.0). Interview data were analysed thematically. Results: More than three-quarters of the 199 patients who returned questionnaires reported weight loss (78.8%) and/or to be eating less (75.9%). More than one third of the people reporting weight loss (35%) and nearly half (45%) of people who reported eating less considered the changes of concern. Patients who were within 6 months of death were found most likely to report concern about either weight loss and/or eating less. The interview data provide insights into the reasons why the symptoms can be experienced as distressing. Conclusion: Weight loss and eating related distress are commonly experienced and previously unresearched problems in people with advanced cancer. Further work is needed to establish if concerns are amenable to interventions that translate into meaningful outcomes for patients and their families

Two photon absorption in quantum dot-in-a-well infrared photodetectors

Two photon absorption processes in InAs/In01.5Ga0.85As/GaAs quantum dot-in-a-well photodetectors are studied using free electron laser excitation. Two photon induced, normal incidence photocurrent, observed in the range of 20-30 mu m, arises from sequential near-resonant two-step transitions involving electron ground to first excited states in the dot, to quantum well final states. We find a two photon absorption coefficient of beta similar to 1x10(7) cm/GW at 26.5 mu m (47 meV) and 0.8 V applied bias. Second-order autocorrelation measurements exhibit two characteristic time constants of similar to 3 and similar to 40 ps. The latter is associated with the intermediate state electron lifetime, whereas the short decay is explained by the involvement of acoustic phonon assisted transitions. (c) 2008 American Institute of Physics