138 Blood samples and 12 hair samples from the district of Angmagssalik, East Greenland, have been analysed for selenium and mercury. It was found that selenium like mercury, was absorbed in accordance with the amount of marine food eaten. The mean blood concentration in the group eating most marine food was 173 and 186 μg Hg/1 for men and women, respectively, while in the group eating the lowest quantity of marine food, the mean values were 86 and 118 μg Hg/1. In blood, the selenium and mercury did not correlate in individuals, but only in groups according to eating habits. On a molar basis, selenium is present in blood in excess as compared to mercury, while the opposite is the case for hair. It is concluded that only part of the selenium interacts with mercury, and that blood, but not hair, reflects present dietary intake. The rich supply of selenium in relation to mercury exposure through the traditional arctic food is probably able to alleviate the hazards from dietary mercury exposure. 相似文献
Listeriosis concerns have led to increased antimicrobial use; reformulation may affect quality. The objective was to determine the effects of potential antimicrobials on quality of natural casing frankfurters. Eleven treatments were used: no antimicrobials (control); 3.0% sodium lactate and sodium diacetate blend (SL+SD); 1.0%, 2.5%, and 3.5% buffered sodium citrate (SC); 1.0%, 2.5%, and 3.5% buffered sodium citrate and sodium diacetate blend (SC+SD); and 1.0%, 2.5%, and 5.0% whey protein peptides (WP). Trained and consumer panelists analyzed sensory characteristics. Cooking yield was unaffected by treatment (P>0.05). Addition of SC and SC+SD decreased pH (P<0.05). Texture profile analysis was conducted. Hunter color values and growth of aerobic bacteria and lactic acid bacteria were monitored over 15 weeks of storage. No samples reached spoilage. SL+SD 3% caused few changes; WP caused changes perceived as negative; and SC and SC+SD caused changes often perceived as positive. 相似文献
Zusammenfassung Zur Verringerung der Knappheit an Organen wird die Einführung eines Marktes für menschliche Organe vorgeschlagen. Personen, die ihre Organe verkaufen, und Personen, die ihre Organe lebend spenden, sind medizinisch den gleichen Gefahren ausgesetzt. Der Verkaufserlös bietet für den Abgebenden eine Einkommenssteigerung, die vielfältig genutzt werden kann. Die auf Schwarzmärkten beobachteten negativen Effekte sollen durch eine strikte Überwachung und Regulierung verhindert werden. Der Markt für Organe kann von zwei getrennten Ankaufsorganisationen geprägt werden. Eine Organisation zahlt die Weiterverkaufserlöse der Organe direkt an die Geber aus, eine andere Organisation investiert sie stattdessen in wohltätige Zwecke und gibt so den Gebern die Möglichkeit, ihr Organ aus rein altruistischen Motiven zu spenden. Die Finanzierung des Systems soll durch das öffentliche Gesundheitssystem bzw. die privaten Krankenversicherungen erfolgen.
Handling of the geothermal fluid, which is typically a complex mixture of salt solution and dissolved gases, is one of the main challenges for designing and operating reliable and efficient geothermal power plants. In the geothermal fluid loop, undesired mineral precipitation and fluid‐material interactions must be prevented and the design and dimensioning of all components must be adapted according to the characteristics of the geothermal fluid. This paper outlines geochemical and process engineering aspects as well as research activities in these fields and introduces the Groß Schönebeck site, which is a central site for geothermal research. 相似文献
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor “daylight PDT” and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed. 相似文献
A mutation and enrichment strategy is described that allows the iso-lation of Acetobacter xylinum mutant strains which are restricted in (keto)gluconate synthesis and produce cellulose more efficiently, even under oxidative conditions. Acetobacter xylinum mutant strains obtained in this way may be very useful in the study of cellulose (over)synthesis and (keto)gluconate metabolism in Acetobacter xylinum, as well as in the improvement of bacterial cellulose fermentation processes. 相似文献
To strengthen the economic pillar in sustainability assessment, the indicator ‘domestic value added’ is introduced. It aims at comparing established and less developed technologies regarding their prospective value added in a country. This is done by classifying a technology’s value added to the developed categories: domestic, potential domestic and non-domestic. Within this paper, two methods for assessing this indicator are introduced focussing on their applicability in a sustainability assessment context. Both methods are tested on a case study comparing two alternative drivetrain technologies for the passenger car sector (battery and fuel cell electric vehicle) to the conventionally used internal combustion engine. The first method is life cycle cost-based whereas the second is based on Input Output analysis. If a life cycle cost assessment is already available for the technology under assessment, the easier to implement life cycle cost-based approach is recommended, as the results are similar to the more complex Input Output-based approach. From the ‘domestic value added’ perspective, the battery electric vehicle is already more advantageous than the conventional internal combustion engine over the lifecycle. Fuel cell electric vehicles have the highest potential to increase their ‘domestic value added’ share in the future. This paper broadens the economic pillar in sustainability assessment by introducing a new indicator ‘domestic value added’ and giving practical information on how to prospectively assess it for existing and less developed technologies or innovations.
We have investigated the magnetic ordering of the frustrated fcc – antiferromagnet HoB12. Below TN= 7.4 K antiferromagnetic order and a complex phase diagram is observed. Above TN neutron scattering experiments show strong diffuse scattering. The diffuse signal indicates strong correlations between rare
earth moments along the [111] direction well above TN. The behavior of this component resembles low dimensional magnets which are known to show long range order only at T = 0.
Close to TN correlations perpendicular to the [111] direction get relevant, they diverge toward TN. Thus we observe a complex ordering process where the frustration is lifted in steps. The experimental data and their interpretation
are presented, some of the possible microscopic origins are discussed.
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