Observer-Based Adaptive Control

The work present in this master thesis relates to output feedback adaptive control and observer design of nonlinear systems, and in particular of robot manipulators. A continuous-time velocity observer and a discrete-time adaptive velocity observer for robots are shown, and an observer backstepping controller is also proposed, which can be used together with both the observers. The resulting closed-loop system is proven to be semiglobally asymptotically stable with respect to both the velocity observation error and the tracking error, and stable with respect to the parameter estimation error. Furthermore an on-line parameter estimation method for a class of nonlinear system is presented, which can be easily extended for the robot equation. Unfortunately the way to use it in combination with the previous observer-controller has not been found and it has not been used in the experiments. In the Appendix A some technical details about the al-gorithm implementation are included, and in the Appendix B a paper already submitted to the 2002 Conference in Decision and Control is included, in which the adaptive output-feedback control scheme is extended for ship control. All the work has been conducted in the Department of Automatic Control, Lund Institute of Technology, Lund University

Output Feedback Adaptive Control of Robot Manipulators Using Observer Backstepping

In this paper we present an observer-based adaptive control scheme for robot manipulators, for which we have both unmeasured velocity and uncertain parameters. Using the observer back-stepping method, a reduced-order adaptive velocity observer can be designed independently from the state-feedback controller, which uses damping terms to compensate the presence of the estimation error in the tracking error dynamics. The resulting closed-loop system is semiglobally asymptot-ically stable with respect to the estimation error and tracking errors. Furthermore a simulated example shows the performance of the control scheme applied to a two-link manipulator

Combination of negative pressure wound therapy and systemic steroid therapy in postsurgical pyoderma gangrenosum after reduction mammoplasty; a case of proven efficacy and safety

Pyoderma gangrenosum (PG) is a rare non-infective inflammatory disease of unknown etiology characterized by cutaneous papulo-pustoles that rapidly evolve into painful ulcerative lesions. Postoperative PG (PPG) is a clinical variant of PG in which pathergic response occurs at surgical sites. It is important to include PG in the differential diagnosis of breast ulceration. An incorrect diagnosis and treatment can potentially worsen the patient state, causing disfigurement with extensive scarring, an unpleasant aesthetic result and produce consequent psychological trauma. We report a case of PPG after bilateral breast reduction mammoplasty treated with negative pressure wound therapy (NPWT) as local treatment for wound dehiscence in combination with systemic steroid therapy. This synergism led to a good aesthetic result. NPWT improved wound perfusion, it decreased the exudate, and promoted adherence of the mammary gland to the pectoral muscle. After 31 days deep sutures were placed to directly close the wound and the patient was discharged. PPG is a rare, devastating occurrence after surgery. Surgeons must know that PPG is an evenience that can occur in otherwise healthy patients and must be considered in the differential diagnosis in case of necrotic ulcers and apparent infection status. NPWT resulted to have benefits in the treatment of PPG, with a role in limiting the size of the defect, avoiding pathergic self-reaction and allowing a faster recovery with higher chances of achieving a better result

Intensive Outpatient Cognitive Behaviour Therapy for Eating Disorder

The aim of this paper is to describe a novel model of intensive outpatient cognitive-behaviour therapy (CBT) indicated for eating disorder patients who are having difficulty modifying their eating habits in response to conventional outpatient CBT. Intensive outpatient CBT is a manual based treatment derived by the CBT-Enhanced (CBT-E) for eating disorders. The treatment has four features that distinguish it from the conventional outpatient CBT-E: (1) it is designed to be suitable for both adult and adolescent patients, (2) it is delivered by a multidisciplinary non-eclectic team trained in CBT, (3) there is assistance with eating, (4) there is a family therapy module for patients under the age of 18 years. Preliminary outcome of intensive outpatient CBT-E are encouraging. The treatment has been applied to 20 consecutive underweight eating disorder patients (age 18.2 ± 6.5 years; BMI 14.6 ± 1.5 kg/m2). Thirteen patients (65%) concluded the treatment, five (25%) were admitted at an eating disorder inpatient unit, and two (10%) prematurely interrupted the treatment. Completers obtained significant weight regain and improvement of eating disorder and general psychopathology. Most of the improvements were maintained at six-month follow-up

Validity and reliability of the Structured Clinical Interview for Depersonalization-Derealization Spectrum (SCI-DER).

This study evaluates the validity and reliability of a new instrument developed to assess symptoms of depresonalization: the Structured Clinical Interview for the Depersonalization-Derealization Spectrum (SCI-DER). The instrument is based on a spectrum model that emphasizes soft-signs, sub-threshold syndromes as well as clinical and subsyndromal manifestations. Items of the interview include, in addition to DSM-IV criteria for depersonalization, a number of features derived from clinical experience and from a review of phenomenological descriptions. Study participants included 258 consecutive patients with mood and anxiety disorders, 16.7% bipolar I disorder, 18.6% bipolar II disorder, 32.9% major depression, 22.1% panic disorder, 4.7% obsessive compulsive disorder, and 1.5% generalized anxiety disorder; 2.7% patients were also diagnosed with depersonalization disorder. A comparison group of 42 unselected controls was enrolled at the same site. The SCI-DER showed excellent reliability and good concurrent validity with the Dissociative Experiences Scale. It significantly discriminated subjects with any diagnosis of mood and anxiety disorders from controls and subjects with depersonalization disorder from controls. The hypothesized structure of the instrument was confirmed empirically

Adapted Physical Activity in post-acute stroke rehabilitation: a 12-month follow-up.

L’ictus è un importante problema di salute pubblica, è causa di morte e disabilità nella popolazione anziana. La necessità di strategie di prevenzione secondaria e terziaria per migliorare il funzionamento post-ictus e prevenire o ritardare altre condizioni disabilitanti, ha portato l’Italia a sviluppare un intervento di Attività Fisica Adattata (AFA) per l’ictus, che permettesse di migliorare gli esiti della riabilitazione. Obiettivo dello studio è di valutare se l’AFA unita all’Educazione Terapeutica (ET), rispetto al trattamento riabilitativo standard, migliora il funzionamento e la qualità di vita in pazienti con ictus. Studio clinico non randomizzato, in cui sono stati valutati 229 pazienti in riabilitazione post-ictus, 126 nel gruppo sperimentale (AFA+ET) e 103 nel gruppo di controllo. I pazienti sono stati valutati al baseline, a 4 e a 12 mesi di follow-up. Le misure di esito sono il cambiamento a 4 mesi di follow-up (che corrisponde a 2 mesi post-intervento nel gruppo sperimentale) di: distanza percorsa, Berg Balance Scale, Short Physical Performance Battery, e Motricity Index. Le variabili misurate a 4 e a 12 mesi di follow-up sono: Barthel Index, Geriatric Depression Scale, SF-12 e Caregiver Strain Index. La distanza percorsa, la performance fisica, l’equilibrio e il punteggio della componente fisica della qualità di vita sono migliorate a 4 mesi nel gruppo AFA+ET e rimasti stabili nel gruppo di controllo. A 12 mesi di follow-up, il gruppo AFA+ET ottiene un cambiamento maggiore, rispetto al gruppo di controllo, nell’abilità di svolgimento delle attività giornaliere e nella qualità di vita. Infine il gruppo AFA+ET riporta, nell’ultimo anno, un minor numero di fratture e minor ricorso a visite riabilitative rispetto al gruppo di controllo. I risultati confermano che l’AFA+ET è efficace nel migliorare le condizioni cliniche di pazienti con ictus e che gli effetti, soprattutto sulla riabilitazione fisica, sono mantenuti anche a lungo termine.Stroke is one of the main public health concerns, because it is a leading cause of death and long-term disability in elderly people. Responding to the need for secondary and tertiary prevention strategies to improve function post stroke and prevent or delay subsequent strokes as well as other disabling conditions, Italy has pioneered development of Adaptive Physical Activity (APA) for stroke. The aim of this study is to assess whether the combination of Adapted Physical Activity (APA) and Therapeutic Patient Education (TPE) improves function and quality of life in stroke survivors. This non-randomized controlled study enrolled 229 patients with mild to moderate hemiparesis, 126 in the experimental group and 103 in the control group. Data were assessed in baseline and at 4 and 12 month follow-up. The outcome measures were 4-month change (that corresponds to 2 months post-intervention in the experimental group) in gait velocity endurance, Short Physical Performance Battery (SPPB), Berg Balance Scale, Barthel Index, Geriatric Depression Scale, the SF-12 and Caregiver Strain Index. Gait endurance, physical performance, balance and the physical component of quality of life score increased significantly at 4 months in the APA group and remained stable in the control group. At 12 month follow-up, the experimental group had a significantly higher improvement on physical performance, quality of life and a lower number of fractures and readmissions compared to the control group. Our results confirm that it is feasible and potentially effective to implement APA programs for elderly patients after stroke and suggest that, when combined with TPE, the effects of a post-rehabilitation APA program are enduring

Anorexia nervosa and body fat distribution: A systematic review

The aim of this paper was to conduct a systematic review of body fat distribution before and after partial and complete weight restoration in individuals with anorexia nervosa. Literature searches, study selection, method development and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Twenty studies met the inclusion criteria and were consequently analyzed. The review had five main findings. First, during anorexia nervosa adolescent females lose more central body fat, while adult females more peripheral fat. Second, partial weight restoration leads to greater fat mass deposition in the trunk region than other body regions in adolescent females. Third, after short-term weight restoration, whether partial or complete, adults show a central adiposity phenotype with respect to healthy age-matched controls. Fourth, central fat distribution is associated with increased insulin resistance, but does not adversely affect eating disorder psychopathology or cause psychological distress in female adults. Fifth, the abnormal central fat distribution seems to normalize after long-term maintenance of complete weight restoration, indicating that preferential central distribution of body fat is a transitory phenomenon. However, a discrepancy in the findings has been noted, especially between adolescents and adults; besides age and gender, these appear to be related to differences in the methodology and time of body composition assessments. The PROSPERO Registry—Anorexia Nervosa and Body Fat Distribution: A Systematic Review (CRD42014008738)

Resting Energy Expenditure in Anorexia Nervosa: Measured versus Estimated

Introduction. Aim of this study was to compare the resting energy expenditure (REE) measured by the Douglas bag method with the REE estimated with the FitMate method, the Harris-Benedict equation, and the Müller et al. equation for individuals with BMI < 18.5 kg/m2 in a severe group of underweight patients with anorexia nervosa (AN). Methods. 15 subjects with AN participated in the study. The Douglas bag method and the FitMate method were used to measure REE and the dual energy X-ray absorptiometry to assess body composition after one day of refeeding. Results. FitMate method and the Müller et al. equation gave an accurate REE estimation, while the Harris-Benedict equation overestimated the REE when compared with the Douglas bag method. Conclusion. The data support the use of the FitMate method and the Müller et al. equation, but not the Harris-Benedict equation, to estimate REE in AN patients after short-term refeeding