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Solution pipes are an important geomorphological feature in carbonate rocks formed by the host rock’s dissolution due to water’s focused flow, indicating the phenomena of water focusing in particular areas. However, their visual exposures are often limited by sediment and vegetation cover, making it challenging to understand their spatial distribution and morphology. In this study, we used geophysical methods such as ground penetrating radar (GPR) and magnetic gradiometer to detect and estimate the spatial distribution of solution pipes in a freshly exposed quarry site in Smerdyna, Poland. Our results indicate that both GPR and magnetometric measurements effectively detect most of the solution pipes, particularly those filled with large amounts of clay and silt particles. The GPR method, in particular, proved to be convenient due to the high contrast of the dielectric constant. The information on the positions and shapes of the pipes obtained based on these methods is crucial in understanding the link between pipe morphology and the physical conditions at the time of their formation. Furthermore, our measurements provided quasi-spatial correlations between pipe positions, the distribution of inter-pipe distances, and the potential relationship between alignments of rock joints and pipe locations. Our study demonstrates the potential of geophysical methods in detecting and understanding solution pipes, which are essential from environmental and climatic perspectives. This information can be used for future studies on pipe formation and environmental impact.

Syzygium aromaticum L. Myrtaceae is one of the plants rich in bioactive compounds that have beneficial effects on the skin. Fermented plant extracts (FPEs) obtained from this plant have recently been exploited as new cosmetic ingredients. The concept of our study was related to the use of clove buds in the fermentation process in order to obtain new cosmetic raw materials with high antioxidant potential. The focus was on evaluating antioxidant activity (AA), total polyphenol content (TPC), and lactic acid efficiency (LAe). For this purpose, the most favourable technological parameters of the fermentation process of clove buds were determined, including the type of microorganisms, initial sugar content, plant raw material content, and fermentation time. The most favourable parameters were correlated with the optimal parameters, which were determined based on response surface methodology (RSM). Based on DPPH and Folin–Ciocalteu assays and GC-MS analysis, optimal points of antioxidant activity against reactive oxygen species (analysed with RSM) were successfully selected, enabling quantitative mathematical representations. The optimisation revealed that using a strain of Lactobacillus rhamnosus MI-0272 in lactic fermentation and plant material (6.40%) and beet molasses (3.20%) results in the highest antioxidant potential of FPE (33.90 mmol Tx/L) and yielding LA with the highest efficiency (96%). The optimised FPE had higher polyphenol content (11.60 mmol GA/L ± 0.14), chelating and antioxidant activity (0.32 mmol Fe2+/L ± 0.01 and 11.60 mmol Tx/L ± 0.09), and Fe3+ ion reduction (49.09 mmol Fe3+/L ± 0.16) than the PE. In addition, the possibility of using the spent plant material remaining after the extraction process to prepare activated carbons capable of treating wastewater was investigated. [ABSTRACT FROM AUTHOR]

Block copolymers utilizing oligomeric poly(pentylene‐co‐hexylene carbonate)diol modified with 2,4‐diisocyanatotoluene and further with 2‐bromo‐N‐(3‐hydroxypropyl)‐2‐methylpropanamide were synthesized and utilized as Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization macroinitiators to obtain a first generation of multifunctional recycling additives with poly(glycidyl methacrylate‐co‐butyl methacrylate‐co‐methyl methacrylate) side chains, which could act as chain extenders. Then, chosen additive was reacted with a radical scavenger, 3,5‐ditertbutyl‐4‐hydroxybenzoic acid (DHBA), to obtain a second generation of reactive additives. Those copolymers had different numbers of epoxy groups per polymer chain, and different number of epoxides opened with DHBA, hence showed a range of properties, and were utilized as reactive modifiers for polylactide (PLA) extrusion melting. The first‐generation modifiers caused an increase in PLA's blends relative melt viscosity, stabilized material properties, and enhanced impact strength, while the second‐generation modifiers with more than 8 % of epoxide ring opened showed worse properties. However, they managed to suppress the UV degradation of PLA blend plates. [ABSTRACT FROM AUTHOR]

The effect of ionizing radiation (γ-rays and electron beam) on anticancer drug delivery systems (DDSs) properties was evaluated concerning potential sterilization. For this purpose, paclitaxel (PTX)-loaded nanoparticles were obtained using a biodegradable, self-developed copolymer of l-lactide and glycolide (PLGA), synthesized in the presence of bismuth 2-ethylhexanoate catalyst. The nanoparticles were obtained with a high encapsulation efficiency of PTX (EE = 94.2%). The average size of the nanoparticles was 253.5 nm. The influence of irradiation (sterilization dose, 25 kGy) on the microstructure and the physicochemical and thermal properties of the polymer matrix was investigated, as well as the effect of irradiation on the morphology and physicochemical properties of the pharmaceutical formulations of the nanoparticles. Additionally, an in vitro drug release study was conducted regarding any alterations in the kinetic profiles of drug release. It was confirmed that the irradiation with both types of ionizing radiation, i.e., γ-rays and electron-beam (EB), slightly decreased the average molecular weight of the polymer matrix. While only negligible changes in the microstructure and thermal properties of PLGA were observed after irradiation with EB, the average length of lactidyl blocks (lLL) in the copolymer chains irradiated with γ-rays decreased from 4.33 to 3.35. Moreover, the contribution of crystalline phase (Xc) in γ-irradiated samples decreased significantly from 35.1% to 22.7%, suggesting a dominant mechanism of chain scission over cross-linking in PLGA samples irradiated with γ-rays. In vitro drug release results demonstrate a sustained and controlled release of PTX from the nanoparticles based on PLGA. The kinetics of drug release was defined as first order with non-Fickian diffusion. Only negligible differences in the kinetic profiles of PTX release from PLGA drug carriers were observed after irradiation. The overall results suggest good resistance of PLGA nanoparticles to irradiation within the conditions used and the great potential of EB in the sterilization process of the polymeric DDSs. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulations of ship propeller operation bearing the name of Propeller Open Water (POW) Tests. The object of tests was a sample ship propeller (PPTC1), the geometrical and kinematic data of which are available, along with the results of model tests, on the official page of the research centre involved in the measurements. The research aimed at verifying the correctness of results of numerical simulations performed in the model and real scale. The results of numerical analyses performed in the model scale were confronted with those measured in the experiment. Then, making use of dimensionless coefficients which characterise propeller’s operation, the recorded model data were extrapolated to real conditions and compared with corresponding results of simulations. Both the numerical simulations and the experimental research were performed for the same propeller load states. The reported research is in line with other activities which aim at developing advanced numerical methods to support the process of ship propeller designing.

Landslides, as one of the main problems in mountainous areas, are a challenging issue for modern geophysics. The triggers that cause these phenomena are diverse (including geological, geomorphological, and hydrological conditions, climatic factors, and earthquakes) and can occur in conjunction with each other. Human activity is also relevant, undoubtedly contributing to the intensification of landslide phenomena. One of these is the production of artificial snow on ski slopes. This paper presents a multimethod approach for imaging the landslide structure in Cisiec, in southwestern Poland, where such a situation occurs. In the presented work, the integration of remote sensing with multi-method geophysical imaging was used to visualize landslide zones, and to estimate ground motion. To verify the uncertainty of the obtained data, the combination of electrical resistivity tomography (ERT), multi-channel analysis of surface waves (MASW), and seismic refraction method (SRT) was supported by synthetic modeling. Using geophysical data with accurate GPS-based topography and a terrestrial laser scanning-based digital terrain model (DTM), it was possible to model the spatial variability and surface area of the landslide more precisely, as well as to estimate the velocity field in the nearest surface more accurately. The final result shows displacement up to 1 m on the ground surface visible on the DTM models, while the geophysical methods confirm the change in internal structure. The proposed methodology is fast, cost-effective, and can be used to image the structure of landslides, where the shallowest parts are usually complex and thus difficult to observe seismically. [ABSTRACT FROM AUTHOR]

The article describes the research on the intake manifold for ultralight aircraft engine Vaxell 100i. It presents the actual and new redesigned manifold construction and points out the design requirements. The results of previously made numerical simulation of air flow inside the manifold are discussed. Computer analysis confirmed the appropriateness of internal guide vanes usage to improve the uniform air distribution between cylinders. For verification, a flow bench test stand was made for multicylinder intake manifold testing. A prototype manifold was built with the possibility of guide vane adjustment. The best variant had almost 5 times better uniformity of air distribution comparing to variant without the guide vane. Flow bench results confirmed the conclusions from numerical simulations.

The presented studies focus on changes in groundwater levels and chemistry, and the identification of important factors influencing these changes on short- and long-term scales in urban areas. The results may be useful for rational and sustainable groundwater planning and management in cities. The studies concerned three aquifers: (1) the shallow Quaternary aquifer, (2) the deep Quaternary aquifer, and (3) the Oligocene aquifer in the capital city of Warsaw (Poland). The spatial variability of groundwater recharge was determined and its changes in time were characterized. The characteristics of groundwater levels were based on long-term monitoring series. The results indicate that urban development has caused overall reduction in infiltration recharge (from 54 to 51 mm/year), which is particularly clear in the city suburbs and in its centre, where land development has significantly densified during the last 30 years. Studies of groundwater levels indicate variable long-term trends. However, for the shallowest aquifer, the trends indicate a gradual decrease of the groundwater levels. In the case of the much deeper Oligocene aquifer, groundwater table rise is observed since the 1970s (averagely c. 20 m), which is related with excessive pumping. Based on the studied results, the groundwater chemistry in the subsurface aquifer indicates strong anthropogenic influence, which is reflected in multi-ionic hydrogeochemical types and the occurrence of chemical tracers typical of human activity. The Oligocene aquifer is characterized by a chemical composition indicating the influence of geogenic factors. [ABSTRACT FROM AUTHOR]