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Gama Nuno Godinho Bruno Barros-Timmons Ana Ferreira Artur 《Journal of Polymers and the Environment》2022,30(1):194-205
Journal of Polymers and the Environment - Lignocellulosic composites are biodegradable, have low cost, neutrality to CO2 emission, easily processed, easily available and pause no health risks,... 相似文献
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Four apparent triploid/diploid mosaic cases were studied. Three of the cases were detected at prenatal diagnosis and the other was of an intellectually handicapped, dysmorphic boy. Karyotypes were performed in multiple tissues if possible, and the inheritance of microsatellites was studied with DNA from fetal tissues and parental blood. Non-mosaic triploids have a different origin from these mosaics with simple digyny or diandry documented in many cases. Three different mechanisms of origin for these apparent mosaics were detected: (1) chimaerism with karyotypes from two separate zygotes developing into a single individual, (2) delayed digyny, by incorporation of a pronucleus from a second polar body into one embryonic blastomere, and (3) delayed dispermy, similarly, by incorporation of a second sperm pronucleus into one embryonic blastomere. In three of the four cases, there was segregation within the embryos of triploid and diploid cell lines into different tissues from which DNA could be isolated. In case 2 originating by digyny, the same sperm allele at each locus could be detected in both triploid and diploid tissues, which is supportive evidence for the involvement of a single sperm and for true mosaicism rather than chimaerism. Similarly, in case 4 originating by dispermy, the same single ovum allele at each locus could be detected in diploid and triploid tissues, confirming mosaicism. In the chimaeric case (case 3), the diploid line had the karyotype 47,XY,+16 while the triploid line was 69,XXY. This suggests a chimaera, since, in a true mosaic, the triploid line should also contain the additional chromosome 16. Supporting the interpretation of a chimaeric origin for this case, the DNA data showed that the triploidy was consistent with MII non-disjunction (i.e. involving a diploid ovum). In the mosaic cases (1, 2, 4), there was no evidence of the involvement of a diploid sperm or a diploid ova, and in triploid/diploid mosaicism, an origin from a diploid gamete is excluded, since all such conceptuses would be simple triploids. In one of these triploid/diploid mosaics detected at prenatal diagnosis by CVS, the triploid line seemed to be sequestered into the extra-fetal tissues (confined placental mosaicism). This fetus developed normally and a normal infant was born with no evidence of triploidy in newborn blood or cord blood at three months of age. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Stuczynski T Siebielec G Korzeniowska-Puculek R Koza P Pudelko R Lopatka A Kowalik M 《Environmental monitoring and assessment》2009,151(1-4):77-91
Primary objectives of our work were to spatially delineate post industrial areas of the EU-27 and indicate key environmental, social and economic sensitivity issues for these regions. The density of industrial sites within NUTS-x regions for EU-27 countries was assessed by using CORINE 2000 land cover layer. A development of postindustrial society in Europe represents a strong geographic diversity. There are distinct historical and current differences between regions which form major groups, comprising similar internal characteristics and definable trends in environmental and socioeconomic sense. Regions grouped into postindustrial clusters are fundamentally different from the European average, and are facing specific problems related to global market and political changes. Eastern postindustrial regions can be characterized as socially and economically weak, exhibiting high unemployment rate, low GDP, negative population growth and a strong environmental pressure, represented by a high density of dump sites. Most of the western EU postindustrial areas have been successfully recovered and moved into new economy as shown by most of the indicators. In urban postindustrial zones, however, emission sources of pollutants seem to continually be a major problem--not necessarily in terms of exceeding thresholds, but through a remarkable difference in the amount of pollutants produced relative to other regions. 相似文献
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Anne Pinton Julia Boubnova François Becmeur Pierre Kuhn Marie-Victoire Senat Julien Stirnemann Marianne Capelle Jonathan Rosenblatt Jérôme Massardier Pascal Vaast Gwenaelle Le Bouar Amélie Desrumaux Laure Connant Laetitia Begue Benoit Parmentier Franck Perrotin Alain Diguet Guillaume Benoist Charles Muszynski Aurélien Scalabre Norbert Winer Jean-Luc Michel Florence Casagrandre-Magne Jean-Marie Jouannic Denis Gallot Perrine Coste Mazeau Emmanuel Sapin Alexis Maatouk Anne-Hélène Saliou Loïc Sentilhes Florence Biquard Nicolas Mottet Romain Favre Alexandra Benachi Nicolas Sananès 《黑龙江环境通报》2020,40(8):949-957
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Biochar, as a soil amendment, can increase concentrations of soil organic matter, especially water-extractable organic carbon (WEOC). This can affect the adsorption-desorption equilibrium between the dissolved solid phases in soil organic matter. Dissolved organic carbon (DOC) represents a small proportion of soil organic matter, but is of significant importance in the soil ecosystem due to its mobility and reactivity. Here, water extracts obtained from twelve non-herbaceous biochars (before, and after, chemical treatment with either H(3)PO(4) or KOH), were tested by Liquid Chromatography - Organic Carbon Detection (LC-OCD) to identify the effects of both pyrolysis conditions and chemical treatments on WEOC content. LC-OCD has the capacity to provide a fingerprint of WEOC, which allows analysis of the various fractions present. WEOC content was affected by both the pyrolysis temperature and the feedstock used. High mineral ash contents deriving from the feedstock can prompt thermochemical reactions of lignocelluloses to produce a relatively high WEOC content, which includes low molecular weight neutrals and humic acids as dominant components. A significant change in WEOC occurred during pyrolysis due to secondary reactions which resulted in a much lower WEOC in the high temperature biochars where fractions of low molecular weight acids and neutrals are dominant. Chemical treatments with H(3)PO(4) or KOH increased WEOC concentration, possibly by promoting hydrolysis reactions on biochar surfaces. These observations assist in assessing the contribution of biochar additions to the soil ecosystem and demonstrate the utility of LC-OCD in providing an understanding of how biochar additions to soil can alter DOC. 相似文献
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The adaptive significance of multiple matings for females is a matter of much controversy. In insects, supplying the female’s
sperm reserves with portions of fresh spermatozoa may be the main function of multiple matings. This simple explanation may
also be applied to other animals which produce large numbers of eggs over prolonged periods of time. We tested the fertility
insurance hypothesis in Montandon’s newt (Triturus montandoni, Amphibia, Salamandridae). T. montandoni females are inseminated internally by spermatophores they have picked up, and subsequently lay eggs fertilized by spermatozoa
released from the spermatheca. We compared the reproductive success of singly and multiply inseminated females of Montandon’s
newt in the laboratory. Multiply inseminated females laid more eggs and had a lower percentage of non-developing eggs than
females who mated only once. Our data suggest that remating increases the reproductive success of multiply inseminated females
by replenishing sperm reserves in the spermatheca or by supplying females with fresh portions of spermatozoa with high fertilizing
capacity.
Received: 7 January 2000 / Revised: 13 September 2000 / Accepted: 7 October 2000 相似文献
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Agnieszka Jdruch Lucyna Falkowska Dominika Saniewska Maciej Durkalec Agnieszka Nawrocka Elbieta Kalisiska Artur Kowalski Jzef M. Pacyna 《Ambio》2021,50(9):1698
The goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment are still elevated. However, the THg level in terrestrial organisms is relatively low, which is because a large proportion of Hg deposited on land is accumulated in organic-rich soils. Regarding the THg concentration, consumption of wildlife and livestock from Poland is safe for humans. Nevertheless, the authors indicate the need for effective environmental monitoring, based on selected bioindicators, which is crucial considering the slowing reduction of Hg emission combined with the consequences of the changing climate.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01505-1. 相似文献