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31.
Gediminas Brazaitis Kęstutis Pėtelis Remigijus Žalkauskas Olgirda Belova Darius Danusevičius Vitas Marozas Gintarė Narauskaitė 《European Journal of Forest Research》2014,133(5):857-869
We analyse the relationships between the main Cervidae [moose (Alces alces), red deer (Cervus elaphus) and roe deer (Capreolus capreolus)] species and a complex of environmental factors in an extensive fragmented landscape of Central Lithuania. The highest determining positive influence on moose density was the proportions of wet forest sites. In forest complexes with fewer proportions of wet sites, the most important factor was the total forest area. The proportion of shrub cover, upland and dense undergrowth area, and road density also has significant effect on moose density. The total area of forest complexes has the highest determining positive influence on red deer density. The highest density of red deer was calculated in large forest complexes (>2,745 ha) with a <17.6 % proportion of pine and <36.5 % of deciduous forests. Other significant factors were core area, road density and urbanization level. Forest edge density has the highest influence on the roe deer populations. The highest density of roe deer was recorded on forest areas with >51 m ha?1 of edges in wet forest (>25.4 %) dominating areas. The proportion of deciduous, coniferous mixed and pine forest, also shrub and density of edges also had significant effect. 相似文献
32.
Vjekoslav Živković Martin Arnold Kristijan Radmanović Klaus Richter Hrvoje Turkulin 《Wood Science and Technology》2014,48(2):239-252
Activation spectra of wood under natural irradiation were investigated in detail in this work. The main purpose was to study colour changes on the wood surface over time and into the depth during natural light exposure and thus to further contribute to the optimization of surface-protecting treatments. In a natural weathering test, three 80-μm-thick strips of fir wood forming the surface layer of a wood composite were exposed to light under a series of glass cut-off filters. Samples were withdrawn at intervals and tested for colour changes. Identification of the most detrimental wavebands of light causing photodegradation was performed based on recorded colour changes. With chronological development of exposure, the colour changes shifted ever deeper into the surface and further into the visible region of the spectrum. A relatively narrow waveband from 360 to 435 nm was identified in the activation spectra to be the most active band, causing the greatest proportion of recorded colour changes. However, also visible light of wavelengths up to 515 nm significantly contributed to colour changes of the surface layers. 相似文献
33.
34.
A sublethal dose (0.1 pmol per honeybee, i.e., approx. 0.9 pmol/g body wt) of the synthetic pyrethroid, deltamethrin, was injected intrathoracically into the hemocoel of emerging bees and the biochemical effects were determined over a period of 3 hr. The variations in hemolymph concentrations of trehalose, glucose, phospholipid, steroid, and diacylglycerol were limited, but large variations were observed for other lipids. Mono- and triacylglycerols increased dramatically 1.5 hr after injections; then a peak of free fatty acid appeared at the same time (3 hr) as the monoacylglycerols reached their maximum and the triacylglycerols started to decrease. Atypical forms of triacylglycerols accumulated from 1.5 hr to a maximum level 2 hr after injection. Then, after 3 hr, the concentrations of regular fatty acids, monoacylglycerols, and atypical triacylglycerols returned to normal while longer-chain fatty acids and different forms of ceride simultaneously appeared. The gut alkaline phosphatase parameters (VM, K, and Hill coefficient) also showed large variations 1.5 and 2 hr after injection, indicating an initial inhibition phase followed by superimposed induction and inhibition mechanisms. These data are discussed according to the hemolymph-lipid transport scheme from the biosynthetic to the utilization sites. Hormone release associated to mitochondrial alteration could be responsible for the observed effects. 相似文献
35.
36.
Ivermectin is one of the most commonly used drugs in pharmacotherapy of parasitic diseases in domestic and wild animals caused
by parasitic nematodes and arthropods. However, ivermectin and other avermectins very often produce side-effects in hosts.
The most dominant clinical symptom of ivermectin toxicity in domestic and wild animals is CNS depression. In nematodes, the
target site of ivermectin’s action is glutamate-gated chloride-channel receptor and GABA receptor. The depressive effect of
ivermectin in mammals might include more than one mechanism; therefore, the anticonvulsive effect of ivermectin against convulsions
caused by lidocaine and strychnine was evaluated. Ivermectin antagonized lidocaine- and strychnine-induced convulsions in
rats, although these have different mechanisms. In the present study, the anticonvulsive ED50 of ivermectin for lidocaine-induced convulsions was 2.44 mg/kg (95% CL 1.67 to 3.57 mg/kg), whereas for convulsions induced
by strychnine it was higher at 4.25 mg/kg (95% CL 2.32 to 3.78 mg/kg). At the same time, both anticonvulsive doses are significantly
lower then the observed LD50 of ivermectin (18.20 mg/kg). Furthermore, flumazenil (0.1 and 0.2 mg/kg), an antagonist of benzodiazepine receptors, antagonizes
just one part of these anticonvulsive effects of ivermectin. Our results show the significant anticonvulsive properties of
ivermectin and support the findings that ivermectin in the CNS of mammals produces multiple inhibitory effects, probably through
participation in the function of GABA-sensitive and GABA-insensitive chloride channels. 相似文献
37.
Vesna Zupanc Gerhard Kammerer Helena Gr
man Igor antavec Rozalija Cveji Marina Pintar 《Land Degradation \u0026amp; Development》2016,27(2):406-415
Hydropower plants on the lower river Sava, Slovenia, were developed without sealing the underground upstream. As a consequence, without the countermeasures of elevating and recultivating, the agricultural land on the river banks would be inundated because of the water‐table increase of the river. To remedy this, the fields were elevated and recultivated. The goal of this study was to assess soil quality and production potential after land raising and recultivation and to answer the question whether it is possible to recover soil quality and crop yield after large‐scale mass manipulation, such as land raising. After recultivation and after the second year of land reuse for the two cultures grass–clover mixture and corn on two sites, Middle Pijavsko and Lower Pijavsko, soil physical and chemical characteristics and crop yields were evaluated. Mixing of topsoil with the second horizon during removal and during backfill with filling material resulted in uneven soil fertility, plant growth and decreased yield. Driving on the refilled second layer with heavy machinery caused soil compaction in the Middle Pijavsko in spite of favourable soil texture (loam, 38·7% sand). On the areas with very high sand content (over 55%) and low clay content (10%), soil compaction was not as severe or persistent. Recultivation measures restored the agricultural land almost to the production potential prior to powerplant construction. Immediate intensive land use (corn) showed less favourable effect on soil characteristics. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
38.
RAPD analysis of interspecific relationships in presumably apomictic Cotoneaster species 总被引:3,自引:0,他引:3
A few of the approximately 300 Cotoneaster species described are diploid but the majority appear to be polyploid. The occurrence of apomixis inpolyploid Cotoneaster species has been reported but never proven with genetic markers. We have used 76 polymorphic RAPD markers to investigate
the breeding system and phenetic grouping of some critical taxa, including a total of 19 plant accessions representing 13
mostly European species in the series Cotoneaster. Three to four individual plants, raised from seed from the same original plant, were analyzed for each of three accessions
to investigate the possible occurrence of apomictic seed set. Absolutely congruent RAPD profiles were encountered among seedlings
from one accession, whereas we found one or two marker differences among seedlings from the other two accessions. Genetic
similarities among the different accessions were analyzed with a UPGMA-derived dendrogram. The most deviant taxon was the
Chinese C. albokermesinus. A group withC. soczavianus and C. tomentosus was rather isolated from the remainder, as was also C. kullensis. Among the remaining taxa, two well supported clusters were found: (1) C. antoninae and C. uralensis, and (2) C. integerrimus and C. raboutensis, whereas the other five species (C. canescens, C. niger, C. scandinavicus, C. juranus, C. cambricus) formed a poorly supported cluster with no clear substructuring. A principal coordinate analysis yielded results that were
in good correspondence with the dendrogram. Again C. albokermesinus appears to be totally isolated from the other species. In addition, two well-defined and rather isolated groups were found:
(1) C. tomentosus and C. soczavianus, and (2) C. antoninae and C. uralensis, with the remainder comprising a loosely defined group.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
39.
Summary The occurrence of chromosomal interchanges was studied in F1 hyrids in two diallel schemes, including nine accessions of Triticum aestivum subsp. spelta, originating from Iran, Europe and North Africa, and the common wheat variety Chinese Spring as a reference. Seven accessions of subsp. spelta differed in one translocation from Chinese Spring. The European accession Grey differed in one or perhaps two interchanges from the reference variety, and Iran 417a showed a difference of three interchanges with Chinese Spring. In total six or perhaps seven interchanges were observed. Thus the number of translocation events in subsp. spelta appeared to be low. One translocation was unique and occurred only in the accession from North Africa. Also one accession from Europe, the landrace Schwarzwald, possibly carried a unique translocation. In both diallels an interchange with a relatively low coefficient of multivalent realisation at first meiotic metaphase was observed in most accessions. The two extra translocations in Iran 417a are considered to be the result of more recent translocation events, whereas the possible second translocation in accession Grey showed such a low coefficient of multivalent realisation that its existence could be doubted. 相似文献
40.
Branimir Urlić Gvozden Dumičić Smiljana Goreta Ban Marija Romić 《Journal of plant nutrition》2016,39(3):389-398
Understanding the mechanisms of phosphorus (P)-use efficiency (PUE) may contribute to enhancing crop P nutrition because species growth variability at low-P is well known. The experiment was carried out to evaluate the response of kale genotypes to different P supply in randomized block design in three replications. Low-P supply led to a decrease in most parameters, whereas an increase was recorded in root growth parameters. Genotypes differed in shoot dry weight (DW), leaf area, root length and area, and shoot and root P content and concentration. Root traits significantly positively correlated with PUE. Genotypes Red Russian (RR) and IJK 17 were superior in terms of shoot DW production at low P supply, and had the highest uptake efficiency. Genotypes IJK 17 and 81 had the highest P utilization efficiency, while Vates blue curled (VBC) showed the lowest PUE. Genotypes had similar shoot P content and concentration at low P supply, but large PUE differences, implying the importance of P utilization efficiency. 相似文献