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101.
We conducted a study within the framework of the interdisciplinary European Mercury Emission from Chloralkali Plants (EMECAP) project to assess exposure to mercury (Hg) and the contribution of Hg emissions from a mercury cell chloralkali plant to urinary mercury (U-Hg) in adults living near the plant. We collected data from questionnaires and first morning urine samples from 75 subjects living near the Tarnow plant in Poland and 100 subjects living in a reference area. Median U-Hg was 0.32 mug/g creatinine (microg/gC) and 0.20 microg/gC, respectively. The median U-Hg was also higher in the amalgam-free subjects living near the plant (0.26 microg/gC) than in the reference group (0.18 microg/gC), but no such association was found in a multivariate analysis. There was a statistically significant positive association between U-Hg and number of teeth with amalgams, a negative association with age and a tendency towards higher U-Hg in female subjects. In the amalgam-free subjects there were statistically significant effects of female sex and fish consumption, and a negative association with age. The additional long-term average air Hg concentration from the plant, based on EMECAP environmental measurements and modelling, was estimated to be 1-3.5 ng/m(3) for the residential study area and should have a very small effect on U-Hg. The other Hg emission sources such as coal combustion facilities located nearby should be taken into account in assessing the overall impact of air Hg on U-Hg in this area.  相似文献   
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Lupine seeds are proposed as a source of valuable protein in human and animal nutrition. However, not only protein content but its bioavailability is important. Thus, the protein digestibility of twenty Lupinus angustifolius varieties seeds and the impact of some factors (protein and polyphenols content, trypsin inhibition and amino acids composition) on the protein digestion were discussed. Composition as well as the digestibility of these seeds was influenced by variety, weather conditions (precipitations) and place of cultivation (soil quality). The average digestibility of the seeds was 46%. The positive impact on the digestibility had the extractivity of the protein. Higher than it was expected activity of trypsin inhibitors (even up to ~32%) in some varieties influenced the protein availability, while the lysine and phenolic compounds content did not affect digestibility. The content of compounds influencing protein digestibility depends both on variety as well as on agronomical conditions.  相似文献   
104.
Motile cilia and homologous organelles, the flagella, are an early evolutionarily invention, enabling primitive eukaryotic cells to survive and reproduce. In animals, cilia have undergone functional and structural speciation giving raise to typical motile cilia, motile nodal cilia, and sensory immotile cilia. In contrast to other cilia types, typical motile cilia are able to beat in complex, two-phase movements. Moreover, they contain many additional structures, including central apparatus, composed of two single microtubules connected by a bridge-like structure and assembling numerous complexes called projections. A growing body of evidence supports the important role of the central apparatus in the generation and regulation of the motile cilia movement. Here we review data concerning the central apparatus structure, protein composition, and the significance of its components in ciliary beating regulation.  相似文献   
105.
Analysis and Automatic Classification of Breath Sounds   总被引:2,自引:0,他引:2  
Analysis of breath sounds (auscultation) is an important part of the diagnosis of pulmonary diseases. An automatic breathsounds classification scheme is suggested. Types of normal and abnormal breath sounds are classified, with the goal of providing the physician with a diagnostic assist device. The classification is performed in two levels. The first level is based on the linear prediction coefflcients, and the second level on energy envelope features. Seven types of breath sounds were classified. Out of 105 trials, the system exhibited only five errors The system can be implemented on a microprocessor and thus can be offered as a low-cost clinical instrument.  相似文献   
106.
Sodium aluminophosphate glasses were evaluated for their bone repair ability. The glasses belonging to the system 45Na2O–xAl2O3‐(55‐x)P2O5, with = (3, 5, 7, 10 mol%) were prepared by a melt‐quenching method. We assessed the effect of Al2O3 content on the properties of Na2O–Al2O3–P2O5 (NAP) glasses, which were characterized by density measurements, DSC analyses, solubility, bioactivity in simulated body fluid and cytocompatibility with MG‐63 cells. To the best of our knowledge, this is the first investigation of calcium‐free Na2O–Al2O3–P2O5 system glasses as bioactive materials for bone tissue engineering.  相似文献   
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ABSTRACT

This study shows the results of the research into the relationships between attitudes toward globalization (accepting, critical, fearful) and psychological factors: identity styles, attitudes toward the Internet, and the quality of friendship. The survey conducted among Polish adolescents and young adults revealed that attitudes toward globalization had a stronger influence on psychological functioning for young adults than for adolescents. The results may help to understand social acceptance factors or disapproval of technological and globalizational changes.  相似文献   
110.
ABSTRACT

Recovery of heavy metals and other useful materials from industrial waste is crucial because it reduces the environmental impact of the production facilities. The selective separation of uranium from such waste might be very important in the context of future energy production and the still essential role of nuclear power in the energy mix. The copper ores, waste from the copper industry, phosphate rocks and phosphogypsum were considered as sources of uranium in these studies. Apart from uranium, these materials also contain other valuable metals, e.g. rare earth elements. In the present work the procedures of extraction of uranium and accompanying metals designed for specific materials – the potential sources of metals, were reported.  相似文献   
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