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Dan Cog?lniceanu Laurentiu Rozylowicz Paul Székely Ciprian Samoil? Florina St?nescu Marian Tudor Diana Székely Ruben Iosif 《ZooKeys》2013,(341):49-76
The reptile fauna of Romania comprises 23 species, out of which 12 species reach here the limit of their geographic range. We compiled and updated a national database of the reptile species occurrences from a variety of sources including our own field surveys, personal communication from specialists, museum collections and the scientific literature. The occurrence records were georeferenced and stored in a geodatabase for additional analysis of their spatial patterns. The spatial analysis revealed a biased sampling effort concentrated in various protected areas, and deficient in the vast agricultural areas of the southern part of Romania. The patterns of species richness showed a higher number of species in the warmer and drier regions, and a relatively low number of species in the rest of the country. Our database provides a starting point for further analyses, and represents a reliable tool for drafting conservation plans. 相似文献
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Acetamide degradation was investigated in a bench-scale upflow anaerobic sludge-blanket (UASB) reactor, successively fed with acetamide, acetate and acetamide, over a period of 343 days, at different hydraulic retention times (t
HR). The reactor was seeded with the sludge previously described [Guyot et al. (1994) Appl Microbiol Biotechnol, 42:452-456], in which methanogenesis from acetamide was performed through a synergistic relationship between an acetamide-degrading, aerobic rod and methanogens. When the reactor was fed acetamide, the chemical oxygen demand (COD) removal efficiency was 86% at volumetric loads less than 1.18 kg COD m–3 day –1. At higher volumetric loads, the efficiency decreased markedly, e.g. 50.9% at a volumetric organic load of 3.39 kg COD m–3 day–1 (1 day t
HR) with an accumulation of both acetamide and acetate. The same reactor, when fed with acetate at t
HR 1 day, reached a high COD removal (99%). Evidence of the inhibition of acetate degradation by acetamide is presented. After a long period (135 days) without feeding the reactor with acetamide, the sludge reactor was still capable of degrading acetamide when this substrate was supplied again. It seems that the synergistic degradation of acetamide by aerobes and methanogens present in the UASB reactor sludge is stable over a long period (343 days), in spite of limiting concentrations of dissolved oxygen in the feed. 相似文献
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Anne Durand Fabien Chauveau Tae-Hee Cho Radu Bolbos Jean-Baptiste Langlois Laure Hermitte Marlène Wiart Yves Berthezène Norbert Nighoghossian 《PloS one》2012,7(11)
Injection of thrombin into the middle cerebral artery (MCA) of mice has been proposed as a new model of thromboembolic stroke. The present study used sequential multiparametric Magnetic Resonance Imaging (MRI), including Magnetic Resonance Angiography (MRA), Diffusion-Weighted Imaging (DWI) and Perfusion-Weighted Imaging (PWI), to document MCA occlusion, PWI-DWI mismatch, and lesion development. In the first experiment, complete MCA occlusion and reproducible hypoperfusion were obtained in 85% of animals during the first hour after stroke onset. In the second experiment, 80% of animals showed partial to complete reperfusion during a three-hour follow-up. Spontaneous reperfusion thus contributed to the variability in ischemic volume in this model. The study confirmed the value of the model for evaluating new thrombolytic treatments, but calls for extended MRI follow-up at the acute stage in therapeutic studies. 相似文献
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The precipitation of iron sulfides potentially offers enough energy and reducing power to sustain life but organisms harnessing this reaction have not to our knowledge been previously described. We isolated a bacterial strain, capable of forming the iron sulfide minerals troilite (FeS), greigite (Fe3S4), and pyrite (FeS2), from subsurface, microbial mats in Mangalia, Romania. This strain, most closely related to strains of Thiomonas sp., forms pyrite only if the redox conditions remain negative (< ?60 mV), sulfides are provided continually (≈1 mM), and the concentration of iron remains low (≤ 0.08 mM) but constant. Pyrite formation by this microbial strain is proposed as an example of biologically controlled mineralization because it is controlled by uncouplers of oxidative phosphorylation, it is larger in living than in dead cells, it is additive (controlled less by the amount of cell surfaces and more by reagents), and it results in the formation of ATP. This study indicates that precipitation and crystal formation can represent an energy resource for life and provides support for the “iron-sulfide world hypothesis” regarding the early evolution of life on Earth. 相似文献
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Alexander Varzari Vladimir Kharkov Alexey G. Nikitin Florina Raicu Kseniya Simonova Wolfgang Stephan Elisabeth H. Weiss Vadim Stepanov 《PloS one》2013,8(1)
Moldova has a rich historical and cultural heritage, which may be reflected in the current genetic makeup of its population. To date, no comprehensive studies exist about the population genetic structure of modern Moldavians. To bridge this gap with respect to paternal lineages, we analyzed 37 binary and 17 multiallelic (STRs) polymorphisms on the non-recombining portion of the Y chromosome in 125 Moldavian males. In addition, 53 Ukrainians from eastern Moldova and 54 Romanians from the neighboring eastern Romania were typed using the same set of markers. In Moldavians, 19 Y chromosome haplogroups were identified, the most common being I-M423 (20.8%), R-M17* (17.6%), R-M458 (12.8%), E-v13 (8.8%), R-M269* and R-M412* (both 7.2%). In Romanians, 14 haplogroups were found including I-M423 (40.7%), R-M17* (16.7%), R-M405 (7.4%), E-v13 and R-M412* (both 5.6%). In Ukrainians, 13 haplogroups were identified including R-M17 (34.0%), I-M423 (20.8%), R-M269* (9.4%), N-M178, R-M458 and R-M73 (each 5.7%). Our results show that a significant majority of the Moldavian paternal gene pool belongs to eastern/central European and Balkan/eastern Mediterranean Y lineages. Phylogenetic and AMOVA analyses based on Y-STR loci also revealed that Moldavians are close to both eastern/central European and Balkan-Carpathian populations. The data correlate well with historical accounts and geographical location of the region and thus allow to hypothesize that extant Moldavian paternal genetic lineages arose from extensive recent admixture between genetically autochthonous populations of the Balkan-Carpathian zone and neighboring Slavic groups. 相似文献
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Alina Vîlcan Ioan Tăut Liviu Holonec Lucica Mihalte Radu E. Sestras 《Trees - Structure and Function》2013,27(3):697-705
A wide range of pests and diseases attacks larch, and over 3 years in an orchard in north-western Romania, the most frequently occurring were larch needle disease (Hypodermella laricis), the case-bearer (Coleophora laricella) and woolly adelgid (Adelges laricis) insects. Their attack on seven larch clones obtained through selection from different geographic populations from Romania was studied. To evaluate the attack intensity, four branches per tree were analysed in the upper, middle and lower third of the crowns in all cardinal directions. According to the position in the crown, a high attack intensity by H. laricis was recorded on the branches in the north direction. A high intensity of C. laricella attack was registered on the upper third of the crown, especially in the east, west and south directions. A positive relationship was identified between the damaged sprouts caused by the C. laricella and A. laricis attack. The differences among the reaction of the clones and the heritability coefficients illustrated that the response to the attacks had a strong genetic determinism, with resistance being clearly influenced by genotype. In addition to the identification of gene sources that are useful for larch breeding, this study offers technical information about the potential to develop efficient treatments based on the attacks on the tree crowns. 相似文献