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[en] Environmental radionuclides (40K, 137Cs, 210Pb, 226Ra) were determined in soils under semi-arid stands, a transition area from thorn to deciduous forest in El Angolo, and heath stands in the Alto Mayo in Northern Peru in order to elucidate their activity level in soil, and to trace underground environment in remote areas of little anthropogenic intervention. Anthropogenic 137Cs was only found in the uppermost portion of the soils in small amount, whereas the 210Pb activity was exceptionally high at the soil surfaces in a tropical stand of Alto Mayo. The results suggest a fallout nuclide, 210Pb, having been transported from local source(s) not to be specified yet. (author)
[en] Since the discovery of the Tyrolean Iceman in 1991 advanced imaging and post processing techniques were successfully applied in anthropology. Specific techniques include spiral computed tomography and 3-dimensional reconstructions including stereolithographic and fused deposition modeling of volume data sets. The Iceman's skull was the first to be reproduced using stereolithography, before this method was successfully applied in preoperative planning. With the advent of high-end graphics workstations and biomedical image processing software packages, 3-dimensional reconstructions were established as a routine tool for analyzing volume data sets. These techniques opened totally new insights in the field of physical anthropology. Computed tomography became the ideal research tool to access the internal structures of various precious fossils without damaging or even touching them. Many of the most precious specimens from the species Autralopithecus (1.8-3.5 Myears), Homo heidelbergensis (200-600 kyears) or Homo neanderthalensis (40-100 kyears) were scanned during the last 5 years. Often the fossils are filled with a stone matrix or other materials. During the postprocessing routines highly advanced algorithms were used to remove virtually these incrustations. Thus it was possible to visualize the morphological structures that lie beneath the matrix. Some specimens were partially destroyed, so the missing parts were reconstructed on computer screen in order to get estimations of the brain volume and endocranial morphology, both major fields of interest in physical anthropology. Moreover the computerized form of the data allows new descriptions of morphologic structures by the means of 'geometric morphometrics'. Some of the results may change aspects and interpretations in human evolution. The introduction of new imaging and post processing techniques created a new field of research: Virtual Anthropology
[en] Complete text of publication follows. Humans are polluting the atmosphere. Due to increasing atmospheric concentration of greenhouse gases and changing stratospheric ozone concentration, both of anthropogenic origin, various quantities in the middle atmosphere display long-term changes and trends. A possibility was indicated of change of such trends in the dynamics in the northern midlatitude middle atmosphere as a whole in the 1990s. To search for such change of trends we use data on winds in the mesopause region, on total columnar ozone, on ozone laminae, on winds in the middle and lower stratosphere, and on peak electron density in the E region of the ionosphere. One group of parameters changes their trends around 1990 (mesopause region winds, E region ionosphere, number of small laminae), the other in the mid-1990s (total columnar ozone, lower and middle stratospheric winds, the overall ozone content in large laminae per profile). Altogether they create a skeleton of scenario of the change of the middle atmosphere dynamics trends in the 1990s, which however needs to be completed by information on the behaviour of dynamics in the upper stratosphere and mesosphere. Drivers of these changes seem to be different for the first date (potential driver is hypothetical change of gravity wave activity) and for the second date (trends in NAO and behaviour of the Arctic winter stratospheric vortex might play some role).
[en] The Argentine development in the nuclear field is analyzed from an anthropological and sociological standpoint. The author has made his 'field work' at the Reactor and Power Plants sector of the National Atomic Energy Commission. She examines the perception that the scientists and other workers of the nuclear field have of the role of its discipline and consequently of its own role in the society. The analysis is carried out into the framework of the situation of nuclear energy in the world and in Argentina in particular
[en] Purpose: The purpose of this study was to review the social scientific literature associated with medical imaging technology. Methods: An extensive search of published studies in nursing, psychology and anthropology was undertaken to support the radiography specific literature. Results: Following a broad definition of technology and its profound influence on society, an analysis of imaging literature revealed a complex relationship between technology and human interactions. Examples are cited for CT, MRI and ultrasound. Conclusion: It is suggested that any attempt to understand imaging technology must place at its centre the perspectives of patients and radiographers. Scientific descriptors must be balanced with equal deliberation given to 'soft technology'
[en] The aim of this paper was to determine the extent of contamination by anthropogeneous radionuclides 137Cs and 90Sr in the bottom sediments from the Barents Sea based on the radioactive activity of the samples taken up in August 1991, among others, from the area close to New Land Island and Francis Joseph Archipelago. The results are based on the phenomenon of vertical migration, in the bottom sediments which is of significant importance from the natural environment point of view. (author)
[en] This study deals with the views and motives of environmental ethics in the articles of Austrian nature and environmental protection associations. There are different ways of arguing: In an anthropocentric point of view nature is seen as a resource for man; human life needs protection an cultivation of nature. The non-anthropocentric point of view is more popular. Nature is not only seen as a resource for human needs and interests. It follows its own aims and purposes, seems to be a valuable being and has to be protected for itself. The study presents the two parent organizations 'Umweltdachverband - OeGNU' and 'Oeko-Buero' and their 45 members. The associations mainly argue from an anthropocentric point of view for the protection of nature and environment. Their motives are the care for human health and quality of life, the ensuring of resources, the leisure-time in nature and patriotism. The anthropocentric arguments perfectly fit into the other articles of these organizations: many of them are dealing with economical, scientifical, recreational and pedagogical affairs. And often they represent interests of agriculture, forestry ore trade. Non-anthropocentric statements are of minor importance and seem to be a way to present the seriousness of their demand for protection of nature and environment. (author)
[en] Complete text of publication follows. Platinum group elements (PGEs) can be naturally found only at very low concentration in the earth crust. However, the uses of PGEs in vehicle exhaust catalysts (VECs), in addition to some other applications cause their anthropogenic emission and spread in the environment. PGE contamination initially occurs in airborne particulate matter (PM), roadside dust, soil, sludge and water, etc.; which finally results in bioaccumulation of these elements in the living organisms. The metallic form of these elements is generally considered to be inert as regards biological reactions. On the contrary, some of their compounds are very toxic and allergenic. The accurate determination of PGEs has been one of the difficult tasks in analytical chemistry because of their ultra-trace concentration in most geological, environmental and biological samples (typically 1-100 ng g-1). Methods like ETAAS and ICP-OES do not provide sufficient sensitivity and detection limits for the direct determination of these elements in such samples. ICP-MS is one of the most sensitive analytical techniques presently available for PGEs determination at trace levels generally having detection limits in the order of ng g-1. However, determination by ICP-MS is hampered by spectral interferences from monoatomic and polyatomic ions produced in the plasma from matrix constituents. Selected PGEs (Pt, Pd and Rh) were determined in the environmental samples (soils and airborne particulate matter) collected from areas strongly affected by automobile traffic and reference samples from unaffected sites. Several spectral overlap interferences (HfO+ in 195Pt determination, ArCu+, ArGa+ and YO+ on 105Pd determination and ArCu+, RbO+, SrO+ and Pb2+ on 103Rh determination) were corrected by means of the mathematical corrections. The samples were digested in aqua regia. Reference material SARM-7 was analysed as well. The results show a significant increase of PGE concentration in samples from sites with heavy automobile traffic in comparison with 'clean' sites. The work was supported by Science and Technology Assistance Agency under the contract No. LPP-0188-06, LPP-0038-06, SK-CZ-0044-07, MEB 080813 and VEGA Nos. 1/4463/07, 1/4464/07 and 1/0272/08.
[en] This study deals with the characterization of a marine sediments profile from the Gulf of Tehuantepec, Mexico. Ten sediment samples obtained from a core of 18.3 m of length were analysed. Although there have been numerous marine sediments studies carried out in Mexico, more are needed to better understand the sea floor formation. Crystallographic, morphologic, physical, chemical and gamma ray activity analysis were carried out on the samples. The analysis results showed a decrease in organic matter content as a function of sea depth; this value is related to the specific surface area. Some hazardous materials as Cr, Mn, Ni, Sr and Hg were also identified by PIXE in some samples, probably due to anthropogenic activity. The presence of uranium a naturally occurring element was found in all the samples, suggesting a migration through all materials of strata, radioactive elements such as 226Ra, 235U, 212Pb, 214Pb, 228Ac, 208Ti, 214Bi, 228Ac and 40K were detected. (author)