Repozytorium Uniwersytetu Śląskiego RE-BUŚ
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Uwagi na temat aksjologicznego wymiaru Konstytucji RP z 1997 r. i jej wykładni w świetle prac Profesora Piotra Winczorka
No full textArtykuł stanowi rozszerzoną i uzupełnioną wersję wystąpienia przedstawionego w trakcie konferencji naukowej poświęconej Profesorowi Piotrowi Winczorkowi. Autorzy podjęli próbę rekonstrukcji teoretycznoprawnych poglądów autora w oparciu o jego wypowiedzi. W szczególności przedmiot prowadzonych badań stanowiły kwestie związane z aksjologią Konstytucji RP. W toku rozważań kolejno podjęto zagadnienia koncepcji porządku prawnego w świetle przepisów ustawy zasadniczej, wartości konstytucyjnych, zasad konstytucyjnych oraz źródeł prawa. Interesującym problemem akcentowanym przez P. Winczorka było to, czy ustawa zasadnicza powinna być oszczędna w kwestii manifestowania wartości. Uzupełnienie badań stanowiła analiza problematyki wykładni prawa w pracach P. Winczorka. Przeprowadzone analizy pozwoliły na sformułowanie wniosku ogólnego, że wiele problemów podjętych przez P. Winczorka znajduje odniesienie w aktualnych sporach konstytucyjnych. Dlatego warto sięgnąć do prac tego autora, którego wypowiedzi można traktować jako wykładnię autentyczną Konstytucji RP dokonywaną przez jednego z głównych jej twórców
New resorbable Ca-Mg-Zn-Yb-B-Au alloys : structural and corrosion resistance characterization
Full text linkNew resorbable Ca32Mg12Zn38Yb18-2xBxAux (x = 1,2) alloys were designed and prepared in order to verify
their use for medical applications as potential short-term implants. Their amorphous structure containing
some crystalline phases (CaZn, CaZn2 and MgZn) was determined by X-ray and neutron diffraction
and electron microscopy methods. The biocorrosion behavior of the plates was tested by hydrogen evolution
measurements, immersion, electrochemical polarization tests, and electrochemical impedance
spectroscopy in Ringer’s solution at 37 C. The corrosion analysis was also supplemented by X-ray diffraction,
photoelectron, and ICP-AES spectroscopy. The corrosion resistivity measurements revealed that the
alloys manifest enhanced corrosion resistance. The corrosion current density for Ca32Mg12Zn38Yb18-
2xBxAux (x = 1, 2) alloys were 18.46 and 8.79 lA/cm2, which is lower than for pure Mg (47.85 lA/cm2)
and Zn (33.96 lA/cm2). A decreasing tendency for hydrogen to evolve as a function of time was noted.
The hydrogen evolution did not exceed 1 ml/cm2 over 1 h and average corrosion rate is calculated as
0.32 g/m2 . h for Ca32Mg12Zn38Yb14B2Au2 alloy after 312 h. The corrosion mechanism of the alloys
includes an anodic dissolution, a hydroxide precipitation, corrosion product layer formation and corrosion
propagation stage
Velocity multistability vs. ergodicity breaking in a biased periodic potential
Full text linkMultistability, i.e., the coexistence of several attractors for a given set of system parameters,
is one of the most important phenomena occurring in dynamical systems. We consider it in the
velocity dynamics of a Brownian particle, driven by thermal fluctuations and moving in a biased
periodic potential. In doing so, we focus on the impact of ergodicity—A concept which lies at the core
of statistical mechanics. The latter implies that a single trajectory of the system is representative for
the whole ensemble and, as a consequence, the initial conditions of the dynamics are fully forgotten.
The ergodicity of the deterministic counterpart is strongly broken, and we discuss how the velocity
multistability depends on the starting position and velocity of the particle. While for non-zero
temperatures the ergodicity is, in principle, restored, in the low temperature regime the velocity
dynamics is still affected by initial conditions due to weak ergodicity breaking. For moderate and
high temperatures, the multistability is robust with respect to the choice of the starting position and
velocity of the particle
Inhibition of celecoxib crystallization by mesoporous silica - molecular dynamics studies leading to the discovery of the stabilization origin
Full text linkIn this article, the effect of mesoporous silica (MS) on the physical stability and
molecular dynamics of the amorphous form of Celecoxib (CEL) is investigated. It has been
proven that the recrystallization process of CEL slows down with increasing the MS content.
Besides the elongation of stabilization time with the increase silica content leads to an
increase in the amorphous drug fraction remaining after the finished crystallization. The
conducted analyses show that the observed inhibition of CEL’s recrystallization is associated
with the formation of a monomolecular drug layer on the silica’s surface. The performed nonisothermal
dielectric studies of CEL + MS systems having both fully and partially amorphous
CEL shows that the biggest impact of the drug’s the temperature dependences of structural
relaxation time τα(T) has a crystalline fraction of the API. Silica, even in high concentration,
does not modify the temperature dependence of structural relaxation of CEL
Nanostructure and morphology of the surface as Well as micromechanical and sclerometric properties of Al2O3 layers subjected to thermo-chemical treatment
Full text linkThe article presents the effect of the thermo-chemical treatment of Al2O3 layers on their nanostructure, surface morphology, chemical composition as well as their micromechanical and sclerometric properties. Oxide layers were produced on EN AW-5251 aluminium alloy (AlMg2) by the method of direct current anodizing in a three-component electrolyte. The thermo-chemical treatment was carried out in distilled water and aqueous solutions of Na2SO4.10H2O and Na2Cr2O7.2H2O. It was shown that the thermo-chemical treatment process changes the morphology of the surface of the layers (the formation of a sub-layer from the Na2SO4.10H2O and Na2Cr2O7.2H2O solutions), which directly increases the thickness of the layers by 0.37 and 1.77 .m, respectively. The thermo-chemical treatment in water also resulted in the formation of a 0.63 .m thick sub-layer. The micromechanical tests indicated a rise in the surface microhardness of the layers in the case of their thermo-chemical treatment in water and the Na2SO4.10H2O solution and a decrease in the case of the layers modified in the Na2Cr2O7.2H2O solution. The highest microhardness (7.1 GPa) was exhibited by the layer
modified in the Na2SO4.10H2O solution. Scratch tests demonstrated that the thermo-chemically treated layers had better adhesive properties than the reference layer. The best scratch resistance was exhibited by the layer after thermo-chemical treatment in the Na2SO4.10H2O solution (the highest values, practically for all the critical loads) which, together with its low roughness and high load capacity, predispose it to sliding contacts
Metal Accumulation and Functional Traits of „Maianthemum bifolium” (L.) F. W. Schmidt in Acid Beech Forests Differing with Pollution Level
Full text linkMaianthemum bifolium (L.) F. W.
Schmidt is a clonal plant with a wide geographical
range throughout Europe and Asia. It is also abundant
as an understory plant of acid beech forests in southern
Poland. The response strategies of this species
to heavy metals and their effects on some functional
traits (height, specific leaf area (SLA), leaf dry matter
content (LDMC), specific rhizome length (SRL) and
rhizomes dry matter content (RDMC)) were tested.
Selected heavy metal concentrations were measured
in leaves, rhizomes and rooting soil of May lily in five
beech forests of southern Poland, mainly including an
industrialised region of Upper Silesia. The contamination
level of these ecosystems was assessed with a
single pollution index. The results show significant
contamination with Pb even at control sites and moderate
with Cd, Zn, Fe and Cu in Upper Silesian forests.
May lily accumulated Pb, Zn and Fe mainly in
rhizomes, but Ni, Cu and Cd were also translocated
to aboveground organs in comparable quantities,
which confirms the indicator value of this plant. May
lily accumulated up to 21 and 30 mg g−
1 Cd, 34 and
90 mg g−
1 Pb and 250 and 553 mg g−
1 Zn in leaves
and rhizomes respectively. Moreover, the accumulation
factors show that May lily accumulates Cd in above- and underground organs in higher amounts
than found in soil. Although high concentrations of
these toxic elements in tissues, no visible damages on
plants were observed, also the measured functional
traits show no apparent relationship with the pollution
level
Soil fauna drives vertical redistribution of soil organic carbon in a long‐term irrigated dry pine forest
Full text linkSummer droughts strongly affect soil organic carbon (SOC) cycling, but net effects on SOC storage are unclear as drought affects both C inputs and outputs from soils. Here, we explored the overlooked role of soil fauna on SOC storage in forests, hy-pothesizing that soil faunal activity is particularly drought-sensitive, thereby reducing litter incorporation into the mineral soil and, eventually, long-term SOC storage.In a drought- prone pine forest (Switzerland), we performed a large-scale irriga-tion experiment for 17 years and assessed its impact on vertical SOC distribution and composition. We also examined litter mass loss of dominant tree species using different mesh-size litterbags and determined soil fauna abundance and community composition.The 17-year- long irrigation resulted in a C loss in the organic layers (−1.0 kg C m−2) and a comparable C gain in the mineral soil (+0.8 kg C m−2) and thus did not affect total SOC stocks. Irrigation increased the mass loss of Quercus pubescens and Viburnum lan-tana leaf litter, with greater effect sizes when meso- and macrofauna were included (+215%) than when excluded (+44%). The enhanced faunal- mediated litter mass loss was paralleled by a many-fold increase in the abundance of meso- and macrofauna during irrigation. Moreover, Acari and Collembola community composition shifted, with a higher presence of drought-sensitive species in irrigated soils. In comparison, microbial SOC mineralization was less sensitive to soil moisture. Our results suggest that the vertical redistribution of SOC with irrigation was mainly driven by faunal- mediated litter incorporation, together with increased root C inputs.Our study shows that soil fauna is highly sensitive to natural drought, which leads to a reduced C transfer from organic layers to the mineral soil. In the longer term, this potentially affects SOC storage and, therefore, soil fauna plays a key but so far largely overlooked role in shaping SOC responses to drought
Podstęp jako znamię przestępstwa zgwałcenia a uboczne motywy podjęcia decyzji o obcowaniu płciowym
Full text linkArtykuł dotyczy problematyki ubocznych motywów podjęcia decyzji o obcowaniu płciowym z perspektywy podstępu jako jednego ze znamion przestępstwa zgwałcenia. Na wstępie autor podaje przykłady sytuacji, w których osoba podejmuje decyzję o obcowaniu płciowym pod wpływem błędu co do ubocznych motywów tej decyzji, aby ułatwić prowadzenie dalszych rozważań. Celem artykułu jest bowiem próba przełamania przyjętej linii interpretacyjnej, zgodnie z którą jako podstęp przy zgwałceniu mogą być traktowane wyłącznie wprowadzenie w błąd co do istotnych – a nie ubocznych – motywów decyzji o podjęciu obcowania płciowego. Posługując się różnymi metodami wykładni i posiłkując się ustaleniami piśmiennictwa i orzecznictwa, autor przedstawia argumenty za oraz przeciwko różnicowaniu ubocznych oraz istotnych motywów decyzji o podjęciu obcowania płciowego. Podział ten z perspektywy przedmiotu ochrony przestępstwa zgwałcenia – wolności seksualnej – wydaje się nie znajdować uzasadnienia, pozbawiając prawnokarnej ochrony grupę osób, zwłaszcza trudniących się prostytucją. Jednocześnie siła argumentów przeciwko zmiany interpretacji skłania do twierdzenia o istnieniu luki prawnej w tym zakresie i konieczności rozpoczęcia pogłębionej dyskusji na temat racjonalnej interpretacji znamienia podstępu
Relationships between Vertical Temperature Gradients and PM10 Concentrations during Selected Weather Conditions in Upper Silesia (Southern Poland)
Full text linkThis paper studies surface air temperature inversions and their impact on air pollution under the background of meteorological conditions in southern Poland. The relationship of temperature gradients and air quality classes with weather conditions in the most urbanized and polluted part of Poland as represented by the Upper Silesia region (USR) within the administrative boundaries of the Górnośląsko-Zagłębiowska Metropolis (GZM) is presented. Based on probability analysis this study hierarchized the role of the selected weather elements in the development of surface-based temperature inversion (SBI) and air quality (AQ). The thresholds of weather elements for a rapid increase in the probability of oppressive air pollution episodes were distinguished. Although most SBI occurred in summer winter SBIs were of great importance. In that season a bad air quality occurred during >70% of strong inversions and >50% of moderate inversions. Air temperature more strongly triggered AQ than SBI development. Wind speed was critical for SBI and significant for AQ development. A low cloudiness favored SBI occurrence altered air quality in winter and spring during SBI and favored very bad AQ5 (>180 µg/m3) occurrence. The probability of high air pollution enhanced by SBI rapidly increased in winter when the air temperature dropped below −6 °C the wind speed decreased below 1.5 m/s and the sky was cloudless. Changes in the relative humidity did not induce rapid changes in the occurrence of bad AQ events during SBI
Linking Spatial-Temporal Changes of Vegetation Cover with Hydroclimatological Variables in Terrestrial Environments with a Focus on the Lake Urmia Basin
Full text linkInvestigation of vegetation cover is crucial to the study of terrestrial ecological environments as it has a close relationship with hydroclimatological variables and plays a dominant role in preserving the characteristics of a region. In Iran, the current study selected the watersheds of two rivers, Nazloo-Chay and Aji-Chay, to systematically investigate the implications and causes of vegetation cover variations under changing environments. These two rivers are among the essential inflows to Lake Urmia, the second largest saline lake on Earth, and are located on the west and east sides of the lake, respectively. There has been a debate between the people living in the rivers’ watersheds about who is responsible for the decline in the level of Lake Urmia—does responsibility fall with those on the east side or with those on the west side? In this study, the normalized difference vegetation index (NDVI) was used as a remotely sensed index to study spatial–temporal pattern changes in vegetation. Moreover, the temperature, precipitation, and streamflow time series were gathered using ground measurements to explore the causes and implications of changing vegetation cover. Discrete wavelet transform was applied to separate the different components of the time series. The Mann–Kendall (MK) test was applied to the time series on monthly, seasonal, and annual time scales. The connections and relationship between the NDVI time series and temperature, pre-cipitation, and streamflow time series and any underlying causes were investigated using wavelet transform coherence (WTC). Land use maps were generated for different years using a support vector machine (SVM) in the final stage. The results indicated that the most dominant monthly, seasonal, and annual hydrological periodicities across the watersheds are 8 months, 6 months, and 2 years, respectively. The increasing vegetation cover during stable hydro-environmental periods revealed unusual conditions in the Aji-Chay watershed and reflected agricultural expansion. The WTC graphs indicated sudden changes in mutual periodicities and time-lags with different patterns between variables, which indicates the increasing anthropogenic activities in both watersheds. However, this was more dominant in the Aji-Chay watershed. The land use maps and investigation of the averaged NDVI maps also denoted that the areas of cultivated land have increased by 30% in the Aji-Chay watershed, and crop types have been changed to the crops with a higher demand for water in both watersheds