Biomedical subjects

G Karg

Publications and source records attributed to G Karg.

6 recordsLinked to original sources

PubMed1999

How optimal are computer-calculated optimal diets?

OBJECTIVE: This paper aims at clarifying the meaning of 'optimal diets'. DESIGN: Two different optimization approaches are considered. Both depart from people's actual diets which in general do not meet all their nutrient requirements. In the first case (non fuzzy approach) the actual diets are modified such that all nutrient intake recommendations are met and the resulting changes in the persons' food habits are as little as possible. In the second case (fuzzy approach) the actual diets are modified such that the persons' food habits undergo little change and the nutrient intake recommendations are met as well as possible. Both approaches are evaluated using data on the actual diets of three randomly chosen participants of the Bavarian Food Intake Survey. RESULTS: With both approaches feasible solutions can be found. The optimal diets computed with the non fuzzy approach satisfy all the persons' nutrient requirements, but make it necessary to change the persons' food habits considerably. When compared to the subjects' actual diets, the optimal diets computed with the fuzzy approach yield improvements for the intake of many nutrients, but in some cases deteriorations also occur (for example, concerning folate, calcium and iodine). So, the process and the results of the fuzzy approach are not 'Pareto efficient'. But it has the advantage that the corresponding optimal diets deviate from the actual diets by no more than about 3-5 kitchen units per day. CONCLUSIONS: The term 'optimal' does not have a general meaning. An 'optimal diet' does not necessarily meet all the nutrient requirements of a person. Optimality only depends on the respective conditions any optimization is based on.

Adult↗

PubMed1998

Sucrose intake in Germany.

The present investigation reevaluated the German National Food Consumption Survey in order to obtain data on sucrose intake and food sources of sucrose intake in Germany. Moreover, it focused on the effect of sucrose intake on nutrient intake. By means of the food composition data base Bundeslebensmittelschlüssel, version II.2, 7-days dietary records of a representative sample of 15,838 persons aged 4 years and older were analyzed. The relation between sucrose and nutrients intake was investigated by variance and regression analyses. Low, moderate, and high sucrose intake categories were defined by means of sucrose density quartiles and comparisons were made for the percentages of persons meeting the German nutrient intake recommendations. Mean daily sucrose intake ranges between 43.2 g/d (f, 51-64 years) and 82.3 g/d (m, 13-14 years). The mean contribution of sucrose to total energy intake is highest with 14% in young age (4-6 years) and decreases to 9% and 7% in 51-64 year old women and men, respectively. The food groups "table sugar", "confectionery and ice cream", "biscuits, cake and pastries", "preserves", "dairy products", and "non-alcoholic beverages" are the main sucrose sources with varying importance in different age groups. The average amount of naturally occurring sucrose in the Germans' diet is estimated to 15-25% of total sucrose intake. Sucrose contributes 80-90% to total disaccharides intake in Germany. With each gram of sucrose the intake of energy rises on the average by 12.5 kcal (52.4 kJ), of protein by 0.3 g (9% of the energy increase), of fat by 0.5 g (34%), and of carbohydrates by 1.8 g (57%). Consequently, the higher the sucrose content of a diet, the lower is the contribution of fat to total energy intake. In contrast, the energy-adjusted effect of sucrose was found to be negative for energy-providing nutrients (except mono- and disaccharides) as well as for all the selected micronutrients, except calcium, vitamin E, vitamin C, and dietary fiber. Accordingly, the comparison between moderate and high sucrose consumers revealed a lower percentage of persons meeting nutrient intake recommendations in the high sucrose category under the condition of a comparable energy intake. This unfavorable effect of high sucrose intake is most prominent in 4-6 year old boys and girls as the groups with the highest sucrose intake. Since from the present data no exact figure for a sucrose or sugars intake recommendation can be deduced, it is suggested to keep on the WHO recommendation for a moderate sugar intake of 10% of energy intake.

Adolescent↗

PubMed1995

[Comparison of dietary surveys in Germany and Great Britain regarding objectives, methodology and results].

Referring to the data of the National Food Consumption Study in Germany and the Dietary and Nutritional Survey of British Adults, this article compares the food intake of German and British adults. Such a comparison is possible because both studies have mainly the same methodology. The comparison of the food intake of German and British adults points out food groups which Germans consume in higher amounts than British people do. To this category belong meat products and sausages, eggs, cheese and cottage cheese, butter, fat for cooking and salad oil, bread and pastries, vegetables, fruit, preserves and soft drinks. The Germans consume less meat, fish and fish products, milk and milk products, pasta, rice and miscellaneous cereals, potatoes, sugar, sweets and tea than the British people do. The consumption of fruit products, alcoholic beverages and coffee is nearly the same in Germany and Great Britain.

Adolescent↗

PubMed1995

[An approach for planning hospital menus using a knowledge-based system].

Menu planning in hospitals is a complex decision problem. Patients expect the menu plan to be healthful and in accordance with their nutritional habits. Furthermore, the menu plan must conform to capacity limits of the kitchen. In this paper we present an approach to computerized food selection and menu composition. The model is based on nutritional knowledge, which is represented in the computer and used for problem solving.

Artificial Intelligence↗

PubMed1990

An improved system for single unit isolation from multiunit nerve recordings by velocity analysis.

A system for recording and decomposition of complex extracellular spike trains by analog computing is presented. Unlike other systems, it is not necessary to establish templates for the analysis. Rather by adjustments of a single knob, the velocity band can be adjusted. The velocity measurement can be made to a precision of better than 1%, where the velocity jitter in individual spikes of a unit becomes apparent. Spike trains on the connective of a stick insect are analyzed which occur during an intersegmental reflex, the CLP reflex.

Action Potentials↗

PubMed1980

[Subchronic toxicity of gamma-Falisan-Universal dry dressing agent to rats].

Doses of 50 mg/kg, 100 mg/kg, and 400 mg/kg of Gamma-Falisan-Universal dry dressing agent (active ingredients including 20 per cent of Lindan and 2.5 per cent of phenyl-mercury acetate) were administered in agar suspension by stomach intubation to rats over 13 weeks, with five applications weekly. The following changes were produced: retardation in body weight, lymphopenia and leucopenia, rise of segment-nuclear neutrophils in peripheral blood, decrease of haematocrit and haemoglobin, as well as rise in activities of leucine aminopeptidase and serum glutamate oxalo-acetate transaminase. The males proved to be more sensitive in the context of their haematological parameters, while the females displayed higher sensitivity in terms of clinico-chemical values. Absolute weight increases were recorded from kidneys and liver of both males and females and from the adrenal gland of females, while weight loss was recorded from the pituitary gland of males. Changes of the same kind were expressed even more strongly, in the context of relative weights of organs. Histopathological changes were recorded from liver, kidneys, and adrenal gland of either sex, and they were histometrically confirmed. Retardation in body weight, rise in activity of leucine aminopeptidase, and weight changes of various organs were significant up to first dosage group. Analogous findings were obtained with regard to microscopic changes in kidneys. Hence, no-effect levels did not occur at all throughout the experiment.

Adrenal Cortex↗