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Biomedical subjects

H Lieth

Publications and source records attributed to H Lieth.

7 recordsLinked to original sources
PubMed1996

The German heavy metal survey by means of mosses.

This is the first attempt to determine pollution with metals throughout the Federal Republic of Germany by analysing moss samples. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupessiforme and Hylocomium splendens were collected at 593 sites and analysed by ICP-AES and AAS for the elements As, Cd, Cr, Cu, Fe, Ni, Pb, V and Zn. Citrus leaves and pine needles were used as reference materials to ensure the quality of the results. In many cases it was possible to trace the areas affected by known sources of heavy-metal emissions in addition to isolated local increases in the values. The moss monitoring programme showed up the highly industrialized and urban locations such as the Ruhr, parts of the Saarland and Baden-Wurttemberg and large areas of eastern Germany. Lower levels of many elements were found in wide stretches of Lower Saxony and Bavaria. The results largely reflect the pollution patterns found in these areas. On the other hand, expected correlations between the effects of traffic (e.g. Pb) and concentrations in moss could not be demonstrated with certainty. The element data yielded by this project are Germany's contribution to the European project 'Atmospheric Heavy Metal Deposition in Europe -- Estimations based on Moss Analysis'.

Air Pollutants↗
PubMed1992

Correlation analysis between some blood properties and atmospheric environmental parameters.

S.W. Tromp made investigations of a weather effect on erythrocyte sedimentation rates (ESR) of human blood by routine checks of the blood of donor groups in Leiden from 1955 to 1985. A higher ESR was found for the summer season and lower ESR for winter and low values occurred soon after a strong cooling spell. In this report, we have continued his work using data for the years 1971-1985 from Leiden (The Netherlands). An influence of the weather on ESR was also found, but this seems to be more complicated than Tromp supposed. Some new aspects are described and elaborated, e.g. ESR already increases before warming is noticed at the ground layer. This is possibly caused by changes in the upper atmosphere, a suggestion that requires further studies. For periods of low ESR, there was a greater number of occlusion fronts passing the Netherlands. The long-term fluctuations of ESR that were found were correlated with sun spot relative numbers only in a few periods. The results of our study justify further research for a variety of other locations around the world.

Adult↗
PubMed1989

Normalization and calculation of lanthanide element concentrations in environmental samples.

A mathematical model for the prediction of lanthanide element concentrations in soil and plant samples is presented. A comparison between predicted and measured lanthanide values in soil and plant samples show, that the model produces good results for the elements in the soil samples and for most elements in plant material. The accuracy of prediction worsens with decreasing concentration of the heavier lanthanide elements. The mathematical model presented is not valid on other environmental samples like aerosols, because no data for these matrices are available yet to calibrate our normalized curves.

Mathematics↗
PubMed1976

[Biophysical questions in ecology and environmental research. Part 1: An analysis of intelligence vs biomass development in humans (author's transl)].

A first analysis of intelligence vs. biomass development in humans shows that the increase of speed to accept new inventions appears not to keep pace with exploding population size. It is suggested to assess more accurately the "collective intelligence" of the human race, an attempt probably useful for several purposes. An equation is presented and used to calculate an upper human population limit for the world suggested by the present intelligence level. The equation suggests 1.5--2.3 billion people educated to the level of industrialized nations. The equation predicts acceptance times for innovations during the early evolution of mankind in the order of 10(6) years. Such a time span seems to be in accordance with archaeological findings for the acceptance of fire as a common tool.

Forecasting↗
PubMed1976

Biophysical questions in ecology and environmental research. Part 2: The extremes of an ecosystem (author's transl).

Some basic differences and developmental aspects of ecosystems are demonstrated. Maximum "energy conductivity" and the pathways of energy flow through ecosystems are discussed as the force, potential, or principle to drive the evolution of the system. A working hypothesis is offered: Ecosystems maximize the total energy flow to optimize temperature stability. The paper stresses in general the need and search for new approaches to analyze the evolution of ecosystems. The hypothesis presented in this paper should be regarded as stimulation for further research.

Ecology↗