Blind extraction algorithm with direct desired signal selection.

In many practical applications we are interested in the extraction of only one desired signal out of a mixture of signals. A disadvantage of most blind extraction approaches proposed in the literature is that they are inefficient in the sense that they also separate or extract undesired signals. To deal with this inefficiency we exploit an a priori guess of direction of arrival related parameters of the desired signal, which serves as a mold. Based on this mold we create linear combinations of noise-free correlation matrices that are used to construct a single matrix with a specific eigenstructure. The eigenvector that corresponds to the smallest eigenvalue of this matrix is the desired extraction filter. Finally it is shown that this approach paves the way to make the algorithm flexible in the utilization of additional a priori information

Patient education and disease activity: A study among rheumatoid arthritis patients

Objective: To determine whether patients experiencing high disease activity derive more benefit from patient education than those experiencing low disease activity. - \ud Methods: Data from a randomized study on the effects of a program of patient education were analyzed retrospectively. Four subgroups were studied: the high disease activity subgroup of patients who had participated in the educational program, the complementary low disease activity subgroup, the high disease activity subgroup of controls, and its low disease activity complement. Patients with erythrocyte sedimentation rate >28 mm/first hour were classified as having high disease activity. Effects on frequency of physical exercises, endurance exercises, and relaxation exercises and effects on health status (Modified Health Assessment Questionnaire, Dutch Arthritis Impact Measurement Scales [AIMS]) were measured. - \ud Results: There were no significant differences between the adherence parameters of the various pairs of groups. Four months after the educational program began, anxiety and depression scores on the Dutch-AIMS had increased among participating patients who were experiencing high disease activity and decreased among those who were experiencing low disease activity. - \ud Conclusions: Patients experiencing high disease activity did not derive more benefit from patient education than those experiencing low disease activity. On the contrary, an increase of anxiety and depression is found in these patients. Further study is needed to confirm our findings

Limited results of group self-management education for rheumatoid arthritis patients and their partners: explanations from the patient perspective

This study aimed to identify the reasons for limited results of group self-management for RA patients and their partners from the patient perspective. Semi-structured interviews with ten male and ten female patients who had participated in group self-management with or without their partner were content analyzed with respect to motivation to participate and the effects of the program on them. The limited effects of the self-management program appear to be linked with low motivation to participate and to change health behavior. The data show that a decline in health and also stressful life events might be associated with the disappointing effects of the program. Three strategies were proposed for improving the program’s effects: (a) provide information about the program in advance to ensure that patients have appropriate expectations. (b) Enhance intrinsic motivation to change health behavior by counseling techniques. (c) Tailoring with respect to motivation and current concerns could help to form more homogeneous groups or could be the basis for a tailored online intervention

Health-related quality of life in sarcoidosis

Purpose of review: The review presents an overview of the scientific publications in the field of health-related quality of life (HRQL) in sarcoidosis. Recent findings: Literature on HRQL in sarcoidosis is limited. HRQL was mainly used as a primary or secondary endpoint in intervention studies. Moreover, most studies have measured HRQL in sarcoidosis by means of the generic questionnaire 36-Item Short-Form Health Survey. Sarcoidosis-specific questionnaires and computer-adapted testing are innovative approaches to the field. Summary: HRQL as a primary or secondary outcome in sarcoidosis studies is still scarce. In addition to the proper definition of the concept, the mode of measurement of HRQL remains a matter of debate. Because health-economical evaluations require data on gained quality of life, future studies on sarcoidosis should include HRQL as the study endpoin

A branch-point approximant for the equation of state of hard spheres

Using the first seven known virial coefficients and forcing it to possess two branch-point singularities, a new equation of state for the hard-sphere fluid is proposed. This equation of state predicts accurate values of the higher virial coefficients, a radius of convergence smaller than the close-packing value, and it is as accurate as the rescaled virial expansion and better than the Pad\'e [3/3] equations of state. Consequences regarding the convergence properties of the virial series and the use of similar equations of state for hard-core fluids in $d$ dimensions are also pointed out.Comment: 6 pages, 4 tables, 3 figures; v2: enlarged version, extension to other dimensionalities; v3: typos in references correcte

A goal management intervention for polyarthritis patients: rationale and design of a randomized controlled trial

Background A health promotion intervention was developed for inflammatory arthritis patients, based on goal management. Elevated levels of depression and anxiety symptoms, which indicate maladjustment, are found in such patients. Other indicators of adaptation to chronic disease are positive affect, purpose in life and social participation. The new intervention focuses on to improving adaptation by increasing psychological and social well-being and decreasing symptoms of affective disorders. Content includes how patients can cope with activities and life goals that are threatened or have become impossible to attain due to arthritis. The four goal management strategies used are: goal maintenance, goal adjustment, goal disengagement and reengagement. Ability to use various goal management strategies, coping versatility and self-efficacy are hypothesized to mediate the intervention’s effect on primary and secondary outcomes. The primary outcome is depressive symptoms. Secondary outcomes are anxiety symptoms, positive affect, purpose in life, social participation, pain, fatigue and physical functioning. A cost-effectiveness analysis and stakeholders’ analysis are planned. Methods/design The protocol-based psycho-educational program consists of six group-based meetings and homework assignments, led by a trained nurse. Participants are introduced to goal management strategies and learn to use these strategies to cope with threatened personal goals. Four general hospitals participate in a randomized controlled trial with one intervention group and a waiting list control condition. Discussion The purpose of this study is to evaluate the effectiveness of a goal management intervention. The study has a holistic focus as both the absence of psychological distress and presence of well-being are assessed. In the intervention, applicable goal management competencies are learned that assist people in their choice of behaviors to sustain and enhance their quality of lif

Goal management strategies and successful adaptation to arthritis

Objective: Persons with polyarthritis often experience difficulties in attaining personal goals due to disease symptoms such as pain, fatigue and reduced mobility. This study examines the relationship of goal management strategies – goal maintenance, goal adjustment, goal disengagement, goal reengagement – with indicators of adaptation to polyarthritis, namely, depression, anxiety, purpose in life, positive affect, participation, and work participation. Methods: 305 patients diagnosed with polyarthritis participated in a questionnaire study (62% female, 29% employed, mean age: 62 years). Hierarchical multiple-regression-analyses were conducted to examine the relative importance of the goal management strategies for adaptation. Self-efficacy in relation to goal management was also studied. Results: For all adaptation indicators, the goal management strategies added substantial explained variance to the models (R2: .07–.27). Goal maintenance and goal adjustment were significant predictors of adaptation to polyarthritis. Self-efficacy partly mediated the influence of goal management strategies. Conclusion: Goal management strategies were found to be important predictors of successful adaptation to polyarthritis. Overall, adjusting goals to personal ability and circumstances and striving for goals proved to be the most beneficial strategies. Practice implications: Designing interventions that focus on the effective management of goals may help people to adapt to polyarthritis