Search results for "Gradation"
showing 10 items of 1275 documents
Differences in gene flow in a twofold secondary contact zone of pond turtles in southern Italy (Testudines: Emydidae:Emys orbicularis galloitalica,E.…
2015
Using virtually range-wide sampling for three pond turtle taxa (Emys orbicularis galloitalica, E. o. hellenica, E. trinacris), we analyse gene flow across their southern Italian contact zone. Based on population genetic analyses of 15 highly polymorphic microsatellite loci and a mitochondrial marker, we show that the general genetic pattern matches well with the current taxon delimitation. Yet, single individuals with conflicting genetic identity suggest translocation of turtles by humans. In addition, we identify in south-western France and the vicinity of Rome populations being heavily impacted by introduced turtles. Cline analyses reveal that the major genetic break between E. o. galloit…
Benchmark study of undrained triaxial testing of Opalinus Clay shale: Results and implications for robust testing
2021
Triaxial testing of argillaceous rocks and shales is significantly more challenging than conventional rock mechanical testing. The challenges are mainly related to the very low permeability of these geomaterials, and their sensitivity to exposure of atmosphere and brines, which induces variations of water content, suction and effective stress. There are currently no international standards to guide service laboratories for robust testing procedures for shales. A benchmark study of undrained triaxial testing was therefore initiated with three leading service laboratories in shale testing, performing 13 tests and using two different methods of establishing sample saturation prior to deformati…
Evaluation of radiation stability of electron beam irradiated Nafion® and sulfonated poly(ether ether ketone) membranes
2022
Proton exchange membranes (PEM), which have been commonly used in fuel cells have raised interest for the application in harsh environments involving ionizing radiation. Therefore, radiation stability and ability to sustain their functionality under the radiation environment are of great interest. Within this study, electron beam irradiation in dose range from 50 to 500kGy was used to evaluate the effects of radiation on the physico-chemical and mechanical properties of two types of PEM: commercial Nafion®117 and sulfonated poly(ether-ether-ketone) (SPEEK) with high degree of sulfonation (DS = 0.75±0.5). SPEEK membrane presented higher mechanical and thermal stability compared to that of Na…
Effect of electron-beam irradiation on structure of ultra high molecular weight polyethylene used in medical implants
2004
Określono wpływ napromieniania strumieniem elektronów dawką równoważną stosowanej w praktyce podczas sterylizacji radiacyjnej endoprotez chirurgicznych (26 kGy) oraz dwukrotnie większą (2 . 26 kGy) na zmianę struktury PE-UHMW o nazwie handlowej „,Chirulen 1120”' (tabela 1) służącego do otrzymywania panewek endoprotez biodrowych. Metodą FT-IR zbadano zmiany strukturalne polimeru, stwierdzając głównie występowanie skutków jego utlenienia (wzrost udziału grup karbonylowych typu ketonowego, estrowego i nadestrowego, grup hydroksylowych oraz winylowych) (rys. 1). Metodą GPC stwierdzono, że napromienianie powoduje także częściową degradację makrocząsteczek (zmniejszenie ciężaru cząsteczkowego o j…
Biotic homogenization of forest bird communities under human influence
2018
Human actions impact biodiversity worldwide. Specialist species are particularly sensitive to environmental degradation whereas generalists may even benefit from habitat changes. As a consequence, specialists are declining while generalists are increasing and, therefore, communities become more similar. This phenomenon is known as biotic homogenization. In boreal forests logging and forest management is the most important factor changing the native habitat. In this thesis I studied if human actions are homogenizing boreal forest bird communities. I further studied if protected areas can maintain their diversity and, thus, prevent homogenization. Through the individual studies, biodiversity …
Potencialidades del consorcio microbiano Curvularia kusanoi -Trichoderma pleuroticola como pretratamiento biológico para la degradación de fuentes fi…
2022
Objective. To evaluate the potentiality of the microbial consortium Curvularia kusanoi L7- Trichoderma pleuroticola as biological pretreatment of high fiber sources destined for animal production. Materials and methods. The Strains used where Curvularia kusanoi L7 and Trichoderma pleuroticola. The degradative potential was evaluated through the production kinetics of cellulolytic (endo-1,4-β-glucanase and exo-1,4-β-glucanase) and ligninolytics enzymes (laccase and peroxidase) in solid submerged fermentation of bran wheat and sugarcane bagasse. The growth of the co culture in plates was analyzed. The effect of the consortium on the carbon mineralization of raw wheat straw was determined and …
Znaczenie rodziny w życiu skazanych poszkodowanych - opinie, oceny i potrzeby
2020
The questions addressed in the present paper concern the family relations of persons deprived of freedom who – remaining in the prison environment – have been degraded, that is convicts occupying the lowest rung in the informal penitentiary system, so-called victimized prisoners. They make a specific community, rejected and humiliated by other inmates. The necessity to ensure safety to them and help them protect their personal characteristics generates difficulties in activities of rehabilitative character. The aim of the research was to show the family relations of people degraded in the prison environment – a subject that has not been studied to date. The method of diagnostic survey was u…
Degradation of Amino-(3-methoxyphenyl)methanephosphonic Acid by Alternaria sp
2002
Alternaria sp. isolated from the surface of carrot ( Daucus carota ) seeds appeared to be able to degrade amino-(4-methoxyphenyl)-methanephosphonic acid using it as a sole source of carbon, nitrogen, and phosphorus for growth.
Isolation, characterization and determination of biotechnological potential of oil-degrading bacteria from Algerian centre coast
2019
Aims The Algerian coastline is exposed to several types of pollution, including hydrocarbons. The aim of this work was to isolate oil-degrading bacteria and to explore the intrinsic bioremediation potential of part of its contaminated harbour. Methods and results A collection of 119 strains, capable to grow on mineral medium supplemented with hydrocarbons, were obtained from polluted sediment and seawater collected from Sidi Fredj harbour (Algiers). Twenty-three strains were selected for further studies. Sequencing of the 16S rRNA gene showed that most isolates belong to genera of hydrocarbonoclastic bacteria (Alcanivorax), generalist hydrocarbons degraders (Marinobacter, Pseudomonas, Gordo…
Impact of electron beam irradiation on fish gelatin film properties
2016
International audience; The objective of this work was to display the effect of electron beam accelerator doses on properties of plasticized fish gelatin film. Electron spin resonance indicates free radical formation during irradiation, which might induce intermolecular cross-linking. Tensile strength for gelatin film significantly increases after irradiation (improved by 30% for 60 kGy). The vapour permeability is weakly affected by irradiation. Surface tension and its polar component increase significantly and are in accordance with the increase of wettability. So, irradiation may change the orientation of polar groups of gelatin at the film surface and crosslink the hydrophobic amino aci…