943 research outputs found
Genetic identification of alien larch taxa : the case of the Tatra National Park
The natural consequences of introducing alien species can be significant. This is particularly a concern where the taxa have an invasive nature of spreading or in those that freely crossbreed with native
species. The hybridization process may lead to impoverishment or even loss of the native gene pool. This is especially dangerous in unique areas that stand out due to their special natural characteristics, such as the Tatra National Park. The determination of the scale of occurrence of alien larch species in the national park and the evaluation of the genetic diversity of the native population is crucial for the conservation of genetic
resources and strictly adheres to the latest conservation genetics trends.
We evaluated the possibility of effective use of molecular markers for taxonomic identification of the native European larch (Larix decidua Mill.), as well as the alien Japanese larch (Larix kaempferi [Lambert] Carriere)
and the hybrid form (Larix × eurolepis Henry). Microsatellite markers were used to analyse the genetic diversity of individuals identified as European larch from natural refuges and artificial plantings.
Of the 148 trees analysed, 105 were identified as the European larch, 38 as Japanese larch, and five as hybrids. The analysis of the molecular variability of two European larch groups of indigenous and artificial
origin showed comparable level of diversity.
This study confirmed the effectiveness of the use of selected molecular markers in identification of larch species, which is difficult based on morphological traits. The results indicate the possibility for the effective use of genetic tools in the creation of protection programmes, especially for naturally valuable sites, based on genetic taxonomic identification and richness verification of protected gene pools
Breeding success of the great tit Parus major in relation to attributes of natural nest cavities in a primeval forest
An overlap in attributes of nest cavities used by Great Tit Parus major across Eurasia suggests similar nest site preferences within the geographical range, although the drivers of these preferences are unclear. To determine whether preferred cavities provide conditions enhancing successful reproduction, we investigated the breeding performance of Great Tits in relation to tree cavity characteristics using data collected during 2008–2011 in primeval conditions (Białowieża National Park, Poland). Here, tree cavities are diverse and superabundant but nesting birds are at risk from a variety of predators. According to expectations, nest losses were high (60 % of Great Tit nests failed), mostly due to predation (69 % of nest failures). The risk of nest failure varied with nest cavity attributes. Compared to successful nests, failures were situated higher above the ground and placed closer to the cavity entrance. Very deep cavities with narrow entrances and strong livings walls provided effective protection against larger predators (e.g., martens, woodpeckers), unable to enter the cavity or pull out the contents. Yet, such holes were no barrier for the smallest predators (e.g., Forest Dormouse Dryomys nitedula), which were able to enter any Great Tit nest cavity and destroyed most of the nests. Avoiding small predators would give a selective advantage to the birds, but this seems hardly possible to achieve. We conclude that tree cavities preferred by the tits show a combination of properties which are a compromise for avoiding predation (the strongest selective pressure) and providing the minimum requirements (sufficient nest illumination, microclimate, protection against nest soaking) for development and growth of young
Aronia melanocarpa Treatment and Antioxidant Status in Selected Tissues in Wistar Rats
Aronia juice is considered to be a source of compounds with high antioxidative potential. We conducted a study on the impact of compounds in the Aronia juice on oxidative stress in plasma and brain tissues. The influence of Aronia juice on oxidative stress parameters was tested with the use of a model with a high content of fructose and nonsaturated fats. Therefore, the activity of enzymatic (catalase, CAT, and paraoxonase, PON) and nonenzymatic (thiol groups, SH, and protein carbonyl groups, PCG) oxidative stress markers, which indicate changes in the carbohydrate and protein profiles, was marked in brain tissue homogenates. Adding Aronia caused statistically significant increase in the CAT activity in plasma in all tested diets, while the PON activity showed a statistically significant increase only in case of high fat diet. In animals fed with Aronia juice supplemented with carbohydrates or fat, statistically significant increase in the PON activity and the decrease in the CAT activity in brain tissue were observed. In case of the high fat diet, an increase in the number of SH groups and a decrease in the number of PCG groups in brain tissue were observed
Application of intravoxel incoherent motion (IVIM) model for differentiation between metastatic and non-metastatic head and neck lymph nodes
Background: Application of intravoxel incoherent motion (IVIM) model parameters, including: true diffusion (D), pseudodiffusion (D*), and perfusion fraction (Fp), for differentiation between metastatic and non-metastatic head and neck lymph nodes. Material/Methods: Diffusion-weighted images/apparent diffusion coefficient (DWI/ADC) images of 86 lymph nodes from 31 cancer patients were analyzed. DWI images were obtained with a 1.5T MRI scanner (Magnetom Avanto); b=0,50, 150, 300, 500, 750, 1000, 1200 s/mm2. Results: In the study group, there were 32 (37%) and 54 (67%) metastatic and non-metastatic lymph nodes, respectively. The mean values of D, D*, and Fp did not differ significantly between metastatic and non-metastatic lymph nodes. Conclusions: IVIM parameters are not useful for differentiation between metastatic and non-metastatic head and neck lymph nodes
Mobile based vibration monitoring and its application to road quality monitoring in deep underground mine
Road quality is an important issue in everyday life for all car owners. This issue seems to be critically important in underground mines, where LHD machines are used for material transport. One of the biggest problems for LHD operation is relatively quick tires degradation. One of possible reasons might be road surface quality, indeed. However, driver's skills as well as ways of machine operation (loading, acceleration, breaking...) might also play a crucial role. Nowadays, many of machines are equipped with onboard monitoring system that allows to monitor basic parameters (speed, torque, temperatures, pressures etc.) at some predefined components. To complete the picture, we propose to use proposed already (but not for mining applications) vibration measurement for road roughness evaluation. To measure vibration acceleration is relatively easy task (we used simple smartphone here), unfortunately method of parametrization and concluding about road quality is still a challenge in mining case. In this paper we have presented a short communication related to first experimental work and some ideas how to deal with this problem using statistical tools for signal modeling
Aronia melanocarpa
Aronia juice is considered to be a source of compounds with high antioxidative potential. We conducted a study on the impact of compounds in the Aronia juice on oxidative stress in plasma and brain tissues. The influence of Aronia juice on oxidative stress parameters was tested with the use of a model with a high content of fructose and nonsaturated fats. Therefore, the activity of enzymatic (catalase, CAT, and paraoxonase, PON) and nonenzymatic (thiol groups, SH, and protein carbonyl groups, PCG) oxidative stress markers, which indicate changes in the carbohydrate and protein profiles, was marked in brain tissue homogenates. Adding Aronia caused statistically significant increase in the CAT activity in plasma in all tested diets, while the PON activity showed a statistically significant increase only in case of high fat diet. In animals fed with Aronia juice supplemented with carbohydrates or fat, statistically significant increase in the PON activity and the decrease in the CAT activity in brain tissue were observed. In case of the high fat diet, an increase in the number of SH groups and a decrease in the number of PCG groups in brain tissue were observed
Synthesis, molecular modelling and biological evaluation of novel heterodimeric, multiple ligands targeting cholinesterases and amyloid beta
Cholinesterases and amyloid beta are one of the major biological targets in the search for a new and efficacious treatment of Alzheimer’s disease. The study describes synthesis and pharmacological evaluation of new compounds designed as dual binding site acetylcholinesterase inhibitors. Among the synthesized compounds, two deserve special attention—compounds 42 and 13. The former is a saccharin derivative and the most potent and selective acetylcholinesterase inhibitor (EeAChE IC50 = 70 nM). Isoindoline-1,3-dione derivative 13 displays balanced inhibitory potency against acetyl- and butyrylcholinesterase (BuChE) (EeAChE IC50 = 0.76 μM, EqBuChE IC50 = 0.618 μM), and it inhibits amyloid beta aggregation (35.8% at 10 μM). Kinetic studies show that the developed compounds act as mixed or non-competitive acetylcholinesterase inhibitors. According to molecular modelling studies, they are able to interact with both catalytic and peripheral active sites of the acetylcholinesterase. Their ability to cross the blood-brain barrier (BBB) was confirmed in vitro in the parallel artificial membrane permeability BBB assay. These compounds can be used as a solid starting point for further development of novel multifunctional ligands as potential anti-Alzheimer’s agents
Lack of specialist nidicoles as a characteristic of mite assemblages inhabiting nests of the ground-nesting wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes)
Bird and mammal nests provide microhabitats that support a range of other species, including invertebrates. However, the variation between communities of nest-dwelling invertebrates in different nests is poorly understood. The major aim of this study was to analyze the assemblage structure of mites from the suborder Uropodina (Acari: Mesostigmata) and from superfamily Crotonioidea (Acari: Oribatida) inhabiting nests of the wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes), located on a forest floor in Białowieża Forest, in eastern Poland. We also assessed the correlation between the nest material used by the birds with the assemblage structure of Uropodina mites, and compared the results with published studies of the nests of other birds and a mammal (common mole, Talpa europaea), and also with communities of mites inhabiting the soil. The field research was conducted in the strict nature reserve of the Białowieża National Park, a near-primeval European temperate forest. In 2019, immediately after the breeding period, 69 wood warbler nests and 439 soil samples were collected. Analyses revealed assemblages of Uropodina mites inhabiting the nests that consisted of 14 species, mostly common soil species. Only five species of oribatid mites from superfamily Crotonioidea were present in the nest material. Analyzed nests had a high percentage of tree leaves and grass blades, whereas moss was the least frequent component of the nest material. The Uropodina mites were more abundant in the nests that had greater amounts of grass blades, but similar relationships were insignificant for the nests with varying amounts of tree leaves or moss. The assemblages of Uropodina mites inhabiting wood warbler nests were very similar to those found in soil and nests of the common mole, but they lacked typical nest-dwelling species of Uropodina (i.e., specialized nidicoles)
Mobile based vibration monitoring and its application to road quality monitoring in deep underground mine
Road quality is an important issue in everyday life for all car owners. This issue seems to be critically important in underground mines, where LHD machines are used for material transport. One of the biggest problems for LHD operation is relatively quick tires degradation. One of possible reasons might be road surface quality, indeed. However, driver's skills as well as ways of machine operation (loading, acceleration, breaking...) might also play a crucial role. Nowadays, many of machines are equipped with onboard monitoring system that allows to monitor basic parameters (speed, torque, temperatures, pressures etc.) at some predefined components. To complete the picture, we propose to use proposed already (but not for mining applications) vibration measurement for road roughness evaluation. To measure vibration acceleration is relatively easy task (we used simple smartphone here), unfortunately method of parametrization and concluding about road quality is still a challenge in mining case. In this paper we have presented a short communication related to first experimental work and some ideas how to deal with this problem using statistical tools for signal modeling
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