Active fiber composites for the generation of Lamb waves.

Active fiber composites (AFC) are thin and conformable transducer elements with orthotropic material properties, since they are made of one layer of piezoelectric ceramic fibers. They are suitable for applications in structural health monitoring systems (SHM) with acoustic non-destructive testing methods (NDT). In the presented work the transfer behavior of an AFC as an emitter of transient elastic waves in plate-like structures is investigated. The wave field emitted by an AFC surface bonded on an isotropic plate was simulated with the finite-difference method. The model includes the piezoelectric element and the plate and allows the simulation of the elastic wave propagation. For comparison with the model experiments using a laser interferometer for non-contact measurements of particle velocities at different points around the AFC on the surface of the plate were performed. Transfer functions defined as the ratio of the electric voltage excitation signal and the resulting surface velocity at a specific point are separately determined for the two fundamental Lamb wave modes. In order to take the orthotropic behavior of the AFC into account the transfer functions are determined for several points around the AFC. Results show that the AFC is capable to excite the fundamental symmetric and antisymmetric Lamb wave mode. The antisymmetric mode is mainly radiated in the direction of the piezoelectric fibers, while the symmetric mode is spread over a larger angle. The amplitudes of the emitted waves depend on the frequency of the excitation as well as on the geometric dimensions of the transducer.

Gender, cohort and geographical differences in 10-year mortality in elderly people living in 12 European towns.

BACKGROUND: In 1988/89, 2586 randomly selected elderly of both sexes born between 1913 and 1918 and living in 19 centres of 12 European countries participated in the SENECA Study on Nutrition and the Elderly in Europe. Differences in nutritional and health status as well in lifestyle factors, namely dietary habits, between the elderly living in the several centres were observed. OBJECTIVE: To study gender, cohort and geographical differences in 10-year mortality in elderly people from the SENECA Study. DESIGN: Longitudinal study. Information on vital status of the elderly people who participated in the baseline study performed in 1988/89 was obtained by standardized procedures in 1999, until 30 April. RESULTS: In all centres, men had higher mortality rates than women. A cohort effect in mortality is observed, particularly in men. A geographical pattern in mortality also more evident in men is shown. In fact, elderly men living in Eastern Europe, represented by the Polish centre, had the highest average hazard rate, 108, while those living in Southern Europe, including the French, the Swiss, the Italian, the Spanish and the Portuguese centres, had the lowest average hazard rates, ranging from 52 in Betanzos/Spain to 67 in the two French towns. Finally, those living in Northern Europe, represented by the Danish, the Dutch and the Belgian centres had intermediate values, from 68 in Roskilde/ Denmark to 85 in Culemborg/the Netherlands. Kaplan-Meier survival curves confirmed the gender, cohort and geographical differences in survival (log-rank test P 0.0001). CONCLUSION: The gender and geographical differences in mortality observed in elderly people living in different regions of Europe put in evidence the potential for increasing the life expectancy in Europe through intervention programs tackling the lifestyle and socio-economic factors behind those differences.

Simulation of elastic wave propagation in cylindrical structures including excitation by piezoelectric transducers.

The development and optimization of non-destructive testing procedures usually needs experimental data. As experiments are time-consuming and expensive to conduct, we would like to use numerical data instead. This is admissible, if the simulation describes the physical experiments accurately. A three-dimensional displacement-stress finite-difference model is presented for a piezoelectric transducer coupled to an anisotropic tube. The allocation of the displacement and stress components on a staggered grid leads to a stable scheme. A full piezoelectric model of the transducer is used, including transverse isotropy in the elastic, dielectric, and piezoelectric constants. Similar to an experiment, elastic waves are excited in the corresponding simulation by applying a voltage signal to the electrodes of the piezoelectric transducer. Predictions of the simulation model for a piezoelectric ring transducer coupled to a carbon-fibre-reinforced shell are compared to experimental results to test the validity of the numerical data.

Fruit and vegetable servings in ten SENECA towns and the impact of the midday meal.

OBJECTIVE: Assessing fruit, vegetable and potato servings in relation to meal pattern. DESIGN: Longitudinal study including dietary assessment in 1988/9 and 1993. SETTING: 10 small European towns. SUBJECTS AND METHODS Counting the number of fruit, vegetable and potato servings in dietary records of 1275 men and women born 1913 to 1918. RESULTS: In the northern towns less than 12% of the subjects consumed 5 or more fruit and vegetable servings and up to 84% consumed only 2 or less servings per day. In the southern towns more than 30% consumed 5 or more servings and less than 20% had only 2 or less servings per day. In 9 of 10 towns a cooked meal at midday contained more fruit and vegetable servings than a cooked meal eaten in the evening. The weight of one serving as calculated from the regression line was 137 g for fruit, 145 g for vegetables and 196 g for potatoes. A significant relationship was found between antioxidant status and vegetables with regard to the number of servings but not to the intake in gram. CONCLUSIONS: RESULTS strengthen the hypothesis that a cooked meal at midday mediated a healthier diet than a cooked meal in the evening. Number of fruit and vegetable servings is a more accurate indication of diversity in vegetable consumption than intake in gram.

Life style characteristics associated with nutritional risk in elderly subjects aged 80-85 years.

A logistic regression model was applied to 627 elderly men and women, who participated in all three data collections of the SENECA study in 1989, 1993, and 1999, to test the hypothesis that nutritional status in 80-85 year old persons was related to functional and cognitive status, but not significantly affected by living arrangement. Additionally, the authors hypothesized that relationships between cognitive status and self-care ability, between self-care ability and living situation, and between cognitive status and living situation would be stronger with increasing age. Nutritional status was categorized as being well nourished (> or = 24) or at nutritional risk (<24) using the 18-item mini-nutritional assessment questionnaire (MNA). Diminished self-care ability was defined as inability to perform all 7 self-care items on the ADL instrument. Respondents were deemed to have possible cognitive impairment if they scored <24 on the MMSE test. Residence situation was categorized as either living alone, with spouse/partner, or with others. Nutritional risk was found to be associated with diminished cognitive status and diminished self-care ability, but not associated with living alone. Elderly people with diminished cognitive function and diminished self-care ability had a more than two times higher risk of being at nutritional risk. In addition, the strength of relationships between cognitive status and self-care ability, self-care ability and living situation, and cognitive ability and living situation all increased over time. In the oldest old lifestyle characteristics and functional ability appeared to be stronger predictors of risk for malnutrition than in younger adults.

Measurement of the dispersion relation of guided non-axisymmetric waves in filament-wound cylindrical structures

To determine the dispersion relation, guided waves are excited in specimens over a broad frequency range. The surface displacements are measured over time and space. The recorded data are analysed using a quasi-three-dimensional spectrum estimation algorithm. In the time domain a fast Fourier transform is used to extract the frequencies. To obtain the wave numbers, in space a two-dimensional matrix-pencil approach is applied to the data set. Using a suitable constitutive model (transversely isotropic or orthotropic) dispersion curves are calculated. Good agreement was found between the experimental and the numerically calculated dispersion relations after adjusting the material parameters. Since the dispersion relation of a structure depends on the mechanical material properties frequency-dependent material parameters can be extracted from the above-mentioned relation between frequency and wave number.

[Nutrition assessment of the elderly based on results of the SENECA Study "Nutrition and the elderly in Europe"]. / Nährstoffaufnahme bei gesunden Betagten aufgrund von Resultaten der SENECA Studie "Nutrition and the elderly in Europe".

The SENECA Study "Nutrition and the elderly in Europe" investigates men and women born 1913-1918 in 20 small traditional towns in Europe. At the age of 74-79 years subjective health was satisfactory or good in 95% of 399 men and 93% of 414 women in 6 study towns. In these subjects suboptimal nutritional blood values were virtually nonexistent. Food intake was low in energy and rich in protein and fat. Lowest European recommended dietary allowances were not reached by all subjects. The even higher values recommended as potentially protective factors were not met by a substantial part of subjects with energy intakes below 6.3 MJ/d. Regularity of food intake was high and had increased over 4 years. Living alone did not adversely affect food intake while low economic situation did.

Assessing eating patterns-an emerging research topic in nutritional sciences: introduction to the symposium.

In order to stimulate food habit research in nutritional sciences, in 1994 the International Union of Nutritional Sciences (IUNS) established Committee II/2 on Nutrition and Food Habits, which has the charge "to review the impact of changing food choice and habits on nutritional status". Within this broad task, priority has been given to methodological aspects of studies on the spatio-temporal structure of food and drink intake. Some principles of the study of eating patterns and the status of this research topic nutrition are described as an introduction to selected papers of a workshop on "Methodology to Identify and to Assess Eating Patterns" organized by the IUNS committee and held during the 16th International Congress of Nutrition in Montreal (Canada) on 28 July 1997.

Meal patterns in the SENECA study of nutrition and the elderly in Europe: assessment method and preliminary results on the role of the midday meal.

The paper discusses the assessment method for meal patterns in the course of the SENECA follow-up survey in 1993 in eight study towns across Europe and relates the percentage of energy intake at the midday meal to geographical latitude, total energy intake, energy intake as snacks, number of cooked meals, time spent at the main meal and intake of milk products, fat and leafy vegetables. A questionnaire for the assessment of meal patterns in western Europe has to include the possibility to assess more than three meals per day as well as a variety of meals at any time of the day. Meal structures vary between cooked meals, bread- or soup-based meals, but may also consist of spoon food, salads or fruit. Positive correlations were found between the percentage of energy intake at the midday meal and the number of cooked meals consumed per day, negative relations were found between the percentage of energy intake at the midday meal and the geographical latitude as well as total energy intake, energy intake in form of snacks and consumption of milk products.

[Swiss Survey in Europe on Nutrition and the Elderly: nutritional status of a Yverdon population aged 74 to 79 years old over a period of four years]. / SENECA Suisse: état nutritionnel d'une population yverdonnoise âgée de 74 à 79 ans, et son évolution sur une période de quatre ans.

In Switzerland the longitudinal SENECA study (Survey in Europe on Nutrition and the Elderly, a Concerted Action of the 3rd European Framework Programme) was implemented in the city of Yverdon-les-Bains. The study investigated the nutritional and health status of 70 to 75-year old elderly living at home, in relation with their food habits, life style, social network and physical activity with a follow-up study 4 years later. Results of the follow-up study, with the subjects aged 74 to 79 years, and changes observed over the 4 years are presented here. The participants reported a rather good self-assessed health and were quite independent in their daily activities. Food and nutrient intakes decreased over the 4-year follow-up, as did physical activity, independence in daily activities and height. However, biological markers (haemoglobin, haematocrit, albumin, lipids and vitamins) of nutritional status showed little change and remained mostly in the normal range. Low energy intake was measured in 21% of the men (< 1500 kcal/d) and in 24% of the women (< 1200 kcal). This is a source of concern since such low energy intakes make it difficult to cover micronutrient requirements. It is therefore important to find ways to maintain or increase the quality of the diet and adequate nutrient intakes.

Living alone does not adversely affect nutrient intake and nutritional status of 70- to 75-year-old men and women in small towns across Europe.

This study determined the relationships between living alone and a variety of sociodemographic variables and dietary intake and nutritional status of 70- to 75-year-old men and women across Europe. Data from nine centers, collected as part of the SENECA study, were selected for analysis. Respondents were categorized as either living alone, living with a spouse/partner only, or living with a spouse/partner and/or other person(s). Analyses included chi-square statistics, t-tests, and analysis of variance, measures of relationships and differences between residential-status groups. The sample included 512 subjects who lived alone, 1017 who lived with a spouse/partner only, and 380 who lived with a spouse/partner and/or other person(s). Variables which differed significantly by living arrangement included higher vitamin A, calcium, riboflavin and water intake by both males and females living alone as compared to either those living with a spouse, those living with others, or both groups. Females who lived alone had lower energy intake than those who lived with other than a spouse/partner, and women who lived alone or as couples versus those who lived with others had lower protein and carbohydrate intakes. Males who lived alone had significantly lower intakes of vitamin C than those who lived with person(s) other than a spouse, but still they were considerably above recommended levels. Respondents who lived with a spouse/partner only were less likely to have an unfavorable BMI status than people in the other two groups. Thus, nutrient intakes of 70- to 75-year-olds across Europe are generally not adversely impacted by living alone, and relative to some nutrients, namely vitamin A, calcium, and riboflavin, their diets are better than those living in one or both of the other residential categories.

Cross-cultural variations and changes in food-group intake among elderly women in Europe: results from the Survey in Europe on Nutrition and the Elderly a Concerted Action (SENECA).

To study cross-cultural variations and changes in intake of food groups in elderly Europeans, longitudinal data on food-group intake from Danish (n = 55), Dutch (n = 65), Swiss (n = 79), and Spanish (n = 46) female participants in the Survey in Europe on Nutrition and the Elderly a Concerted Action (SENECA) were compared. Participants were born between 1913 and 1918. Information on food intake was obtained with use of the same diet-history method at all sites and in both 1988-1989 and 1993. Actual food intake was coded according to the Eurocode system, the applicability of which for European multicenter studies was evaluated in this study. All participants, regardless of site, reported consumption of milk, grain products, and vegetables, and almost all ate meat, fats, and fruit. Fewer women ate eggs, fish, and sugar. The variations between the sites were in the food groups consumed and the types of foods within the groups. Spanish women appeared to have the most healthy food-intake pattern. They also had more changes in their dietary pattern than did women in the other countries. The Eurocode was adequate for describing the actual food intake of elderly women in four European towns. The coding for meat, however, was ambiguous and should be revised.

Nutrition and the quality of life: a measure for the outcome of nutritional intervention.?

The quality of life in old age is dependent on many resources and not just on health. Quality of life cannot be a measure for the outcome of nutritional interventions in old age. Risk patterns shift with advancing age and the outcome of a nutritional intervention may have to be evaluated under different circumstances. Although the impact of nutrition as a preventive measure decreases with age, the value of food intake for social structure, self-esteem, enjoyment, and situation awareness gradually increases.

Life-style: marital status, education, living situation, social contacts, personal habits (smoking, drinking). Euronut SENECA investigators.

Data on marital status, living conditions and social contacts of 2586 elderly persons living in 19 towns from 12 European countries, who were born between 1913 and 1918, and who participated in the Euronut SENECA study on Nutrition of the Elderly in Europe, reflect on the whole a high quality of life in the elderly population of these small traditional European towns. Housing offers adequate comfort in general and many elderly people have access to gardens. In most survey towns the majority of men and women of this age group have at least one child within the town or nearer. In some of the southern and eastern towns 40% or more live with their children. In most survey towns 30-50% of the women live alone (more than 50% in the Danish and Norwegian towns Roskilde and Elverum) but in general social nets are strong enough to prevent the danger of acute isolation. But in four towns (Roskilde/Denmark, Chateau Renault-Amboise/France, Elverum/Norway and Padua/Italy) 10-13% of all women lived alone and did not know a neighbour well enough to call on for help. In three towns (Monor/Hungary, Vila Franca de Xira/Portugal and Marki/Poland) social contacts were distinctly less frequent than in all other towns and participation in community activities virtually non-existent. These were the same towns in which substantial groups reported food budgeting problems. Danger of isolation, however, seemed to be rather low. A high intensity of social contacts and no danger of acute isolation in spite of relatively few available children was noted in the German-speaking town of Switzerland (Burgdorf). Further analyses will have to test whether food consumption or nutritional status is related to any of the studied life-style factors.

Dietary habits and attitudes. Euronut SENECA investigators.

This chapter describes data on dietary behaviour collected from 2586 elderly persons, born between 1913 and 1918 and living in 19 towns from 12 European countries, who participated in the Euronut SENECA Study on Nutrition of the Elderly in Europe. Groups of elderly subjects with particular dietary habits were identified. They included those persons having low or high meal frequencies, those not having regular cooked meals, those consuming home-produced foods, those having special interest or awareness in nutrition, those eating alone and those with food-budgeting problems. In future analyses, we shall endeavour to determine whether the dietary intake, nutritional status and health of these groups are related to their dietary habits.

The family and the help needs of disabled elderly in two Swiss cities.

The purpose of the present article is to describe the situation in which informal help is no longer sufficient, and thus to contribute to the understanding needed for the planning of organized services. Interviews were conducted with a stratified random sample of 480 over 65-year-olds in two urban areas of Switzerland representing a 80.4% response rate. The married elderly receive most of their daily help from their spouse; daily nursing assistance to the widowed elderly comes from a family member (60-70%) or from organized services, whereas neighbours may provide occasional help in household activities. Unmarried old people in need of daily help live almost always in stationary institutions. Under the conditions examined, domiciliary services for the disabled elderly serve to complement informal help rather than to replace it. Supporting and motivating informal caregivers would seem to be a promising strategy toward more efficient domiciliary services.

[Handicaps and needs of the elderly. A multifactor epidemiologic study under urban conditions]. / Behinderungen und Bedürfnisse Betagter. Eine multifaktorielle epidemiologische Studie unter städtischen Bedingungen.

As the number of old people increases, the need for a reliable statistical basis for socio-medical planning becomes more and more evident. Results of a representative survey in two cities of German-speaking Switzerland are presented, including correlations between the extent of need for assistance and predisposing factors. About half of the elderly are not disabled in everyday life, but 9.3% of the 66- to 75-year-olds and 46.1% of the over 85-year-olds are in need of regular daily assistance. In addition to age, male sex and being unmarried turned out to be independent predisposing factors for an increased need for help. Women were in the majority in some particular disturbances, but as a whole their need for assistance was less than among men. Socio-economic status was the most important risk factor for need for assistance. In comparison to those from higher social classes, elderly from the lowest class are round five times as often in nursing homes and ten times as often in residential homes. Their need for all forms of assistance is increased, and, in particular, they need much more daily household help than those in higher socio-economic groups. The number of admissions to institutions could be considerably reduced if more of these elderly persons could be offered ambulatory household assistance services. Furthermore, elderly of low socio-economic status tend to live more in unsuitable dwellings, eat food of lower quality, get less physical exercise, are less often of normal body weight, and have functional disturbances more often. Among the predominant factors associated with the need for nursing care are disturbances of orientation, incontinence and visual disturbances, whereas cardiovascular diseases and malignant tumors are of little importance in this context. The situation is different with respect to the need for household help, which is particularly frequent among persons with disturbances of the extremities. These in turn are about twice as frequent among elderly of lower social class than among those who are better-off. In the population under study about 40% of the elderly requiring daily nursing assistance are cared for in their homes, with their own family members providing most of the assistance. This is less often the case in the lower socio-economic groups. Our analyses make it possible, for the first time in Switzerland at least, to demonstrate clearly the important role social status, family situation and gender play in determining the level of disability and need for assistance among the elderly.(ABSTRACT TRUNCATED AT 400 WORDS)

[The care of elderly patients by their relatives]. / Pflege von betagten Patienten durch ihre Angehörigen.

New concepts are needed for the still increasing number of geriatric patients who require long term institutional care and for the often difficult situation of caregiving relatives. We investigated the possibility to integrate relatives of institutionalized patients in the nursing care. 323 geriatric patients were randomly selected and the relatives contacted. Only four (1%) had no relatives or friends. Of 86% of the patients it was possible to interview 343 relatives or close friends. Of those 147 (43%) were favorably disposed towards a cooperation in the care with the ward staff. Persons willing to cooperate were characterized by female sex, middle class status, good health, not too demanding jobs, and close contacts prior to institutionalization of their next of kin. In a second part 29 of 196 relatives were willing to take part in a pilot project. Unfortunately, for technical reasons only five patients could be hospitalized on the experimental ward in the given time. The practical experience demonstrated that relatives can cooperate on a part time basis with the nursing staff in the care of institutionalized geriatric patients. It is estimated that probably 12% of the geriatric patients in institutions have relatives willing and capable to take part in the nursing or other activities on the ward. Smaller nursing facilities appear more suitable than large geriatric clinics for this type of cooperation.