Refined myoelectric control in below-elbow amputees using artificial neural networks and a data glove

PURPOSE: To develop a system for refined motor control of artificial hands based on multiple electromyographic (EMG) recordings, allowing multiple patterns of hand movements. METHODS: Five subjects with traumatic below-elbow amputations and 1 subject with a congenital below- elbow failure of formation performed 10 imaginary movements with their phantom hand while surface electrodes recorded the EMG data. In a training phase a data glove with 18 degrees of freedom was used for positional recording of movements in the contralateral healthy hand. These movements were performed at the same time as the imaginary movements in the phantom hand. An artificial neural network (ANN) then could be trained to associate the specific EMG patterns recorded from the amputation stump with the analogous specific hand movements synchronously performed in the healthy hand. The ability of the ANN to predict the 10 imaginary movements offline, when they were reflected in a virtual computer hand, was assessed and calculated. RESULTS: After the ANN was trained the subjects were able to perform and control 10 hand movements in the virtual computer hand. The subjects showed a median performance of 5 types of movement with a high correlation with the movement pattern of the data glove. The subjects seemed to relearn to execute motor commands rapidly that had been learned before the accident, independent of how old the injury was. The subject with congenital below-elbow failure of formation was able to perform and control several hand movements in the computer hand that cannot be performed in a myoelectric prosthesis (eg, opposition of the thumb). CONCLUSIONS: With the combined use of an ANN and a data glove, acting in concert in a training phase, amputees rapidly can learn to execute several imaginary movements in a virtual computerized hand, this opens promising possibilities for motor control of future hand prostheses.     

The use of risk estimation models for the induction of secondary cancers following radiotherapy

Theoretical predictions of cancer risk from radiotherapy may be used as a complementary criterion for the selection of successful treatment plans together with the classical approach of estimating the possible deterministic effects. However, any such attempts must take into consideration the specific features of radiation treatment. This paper explores several possible methods for estimating the risk of cancer following radiotherapy in order to investigate the influences of the fractionation and the non-uniformity of the dose to the irradiated organ. The results indicate that dose inhomogeneity plays an important role in predicting the risk for secondary cancer and therefore for predictive purposes it must be taken into account through the use of the dose volume histograms. They also suggest that the competition between cell killing and the induction of carcinogenic mutations has to be taken into consideration for more realistic risk estimations. Furthermore, more realistic parameters could be obtained if this competition is also included in analyses of epidemiological data from radiotherapy applications.     

Morale in the oldest old: the Umeå 85+ study

OBJECTIVE: to describe morale among the oldest old, and to investigate which social, functional and medical factors are associated with morale in this population. DESIGN: a cross-sectional study. SETTING: a population-based study in the municipality of Ume?, a city in Northern Sweden. SUBJECTS: half of the 85-year-old population, and the total population of 90-year-olds and > or = 95-year-olds (95-103) were asked to participate (n = 319) and 238 were interviewed. METHODS: structured interviews and assessments during home visits, interviews with relatives and caregivers and review of medical charts. The 17-item Philadelphia Geriatric Center Morale Scale (PGCMS) was used to measure morale. Participants were assessed with the Barthel Activities of Daily Living (ADL) Index, Geriatric Depression Scale (GDS-15), Mini-Mental State Examination (MMSE), Mini Nutritional Assessment (MNA), and a symptom questionnaire. Multiple regression analyses were conducted to find independent factors to explain the variation in the PGCMS score. RESULTS: eighty-four per cent (n = 199) of those interviewed answered the PGCMS. Three-quarters had middle range or high morale. GDS score, type of housing, previous stroke, loneliness and number of symptoms, adjusted for age group and sex, explained 49.3% of the variance of total PGCMS score. CONCLUSIONS: a large proportion of the oldest old had high morale. The most important factors for high morale were the absence of depressive symptoms, living in ordinary housing, having previously had a stroke and yet still living in ordinary housing, not feeling lonely and low number of symptoms. The PGCMS seems applicable in the evaluation of morale among the oldest old.     

Opening up: psychiatric nurses' experiences of participating in reflection groups focusing on the use of coercion

Psychiatric staff report that the use of coercion towards patients in psychiatric care engenders feelings of discomfort and conflicts. The aim of this study was to describe psychiatric nurses' experiences of participating in reflection groups focused on the use of coercion, in relation to their views regarding systematic clinical supervision and staff support. Twenty-one nurses who had participated in reflection groups were interviewed retrospectively. The structured interview focused on: (i) their views of clinical supervision and support in general; (ii) their views of clinical supervision and support specifically concerning the use of coercion; and (iii) their experiences of participating in groups reflecting the use of coercion. Nurses were largely positive about participating in reflection groups, as expressed in the subthemes: having time for reflection; being confirmed; gaining new perspectives; sharing fellowship with colleagues; and relating more effectively to patients. Complications concerning participation in the reflection groups and other forms of clinical supervision as reported by nurses were: providing time for participation; having a common aim; being vulnerable in difficult situations; and assuming that the need for supervision and support could indicate that they were not coping with their job.     

Non-word repetition and non-word discrimination in Swedish preschool children

By looking at data on expressive phonology, non-word repetition, non-word discrimination and phonological sensitivity in two groups of Swedish children, the common basis for tasks tapping into different levels of phonological processing is discussed. Two studies were performed, one including children with language impairment (LI) and one including children with normal language development (NL). A discrimination task consisting of non-word pairs differing in one phoneme was developed. In both groups there was a significant correlation between non-word repetition and phoneme identification. In children with LI phoneme identification was significantly correlated with expressive phonology. In children with NL non-word repetition correlated significantly with non-word discrimination, which was linked both to rhyme recognition and phoneme identification. Non-word discrimination might be equally useful as non-word repetition as an early screening tool and would circumvent the confounding factor of an expressive phonological impairment as well as decrease the amount of complicating factors involved in scoring procedures.