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A-kinase anchoring protein-mediated compartmentalization of pro-survival signaling in the retina

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Neural Regeneration Research 2025年第2期20卷 479-480页

作者： joanna Mackiewicz Tomasz Boczek Department of Molecular Neurochemistry Medical University of LodzLodzPoland

The retina plays a fundamental role in the process of vision,serving as the primary interface between external visual stimuli and the central nervous *** the retina is exposed to a variety of environmental stresses and deleterious insults,it is susceptible to a spectrum of pathological conditions that can detrimentally affect *** often leads to irreversible vision loss due to the injury of specific cell *** instance,inherited retinal degeneration and age-related macular degeneration can lead to the death of photoreceptors,while conditions like glaucoma and optic nerve injury can result in the loss of ganglion *** precise pathological mechanisms driving retinal degeneration remain largely elusive,although research utilizing mouse models suggests that disruptions in intracellular signal transduction pathways may play a pivotal *** pathways within the retina orchestrate various aspects of retinal physiology,including phototransduction,synaptic transmission,and neuronal survival.

关键词： degeneration utilizing irreversible

Bioactive injectable composites based on insulin-functionalized silica particles reinforced polymeric hydrogels for potential applications in bone tissue engineering

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Journal of Materials Science & Technology 2022年第10期105卷 153-163页

作者： Aleksandra Krajcer joanna Klara Wojciech Horak joanna Lewandowska-Łańcucka Faculty of Chemistry Jagiellonian UniversityGronostajowa 2Kraków 30-387Poland AGH University of Science and Technology Faculty of Mechanical Engineering and RoboticsDepartment of Machine Design and TechnologyAl.Mickiewicza 30Kraków 30-059Poland

Novel bioactive injectable composites based on biopolymeric hydrogels reinforced with insulin-functionalized silica particles were *** insulin(INS)was immobilized on the surface of amine-modifed silica particles employing covalent attachment by EDC/NHS chemistry and via electrostatic *** resulting formulations were examined for the morphology(SEM),chemical composition(FTIR,XPS)as well as protein *** facilitate the injectability and support the bone regeneration,developed particles were dispersed in biopolymeric sol composed of collagen,chitosan and lysinemodifed hyaluronic acid and crosslinked with *** means of rheological study,the sol-gel in situ transition of obtained systems was *** was found in vitro study that MG-63 cells cultured on the developed composites exhibit signifcantly higher alkaline phosphatase(ALP)activity,compared to the pristine ***,the biomineralization ability in the simulated body fluid(SBF)model was also *** fndings suggest that proposed herein novel hydrogel-based composites might be the promising formulation for regeneration of bone defects,especially as a less-cost effective support/alternative for BMP-2 systems.

关键词： Injectable composites Biopolymers Insulin-functionalized silica particles Bone tissue engineering

Representative elementary volume analysis of polydisperse granular packings using discrete element method

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Particuology 2016年第4期14卷 88-94页

作者： joanna Wiacek Marek Molenda Institute of Agrophysics Polish Academy of Sciences Doswiadczalna 4 20-290 l.ublin Poland

The representative elementary volume （REV） for three-dimensional polydisperse granular packings was determined using discrete element method simulations. Granular mixtures of various sizes and particle size distributions were poured into a cuboid chamber and subjected to uniaxial compression, Findings showed that the minimum REV for porosity was larger compared with the REV for parameters such as coordination number, effective elastic modulus, and pressure ratio. The minimum REV for porosity and other parameters was found to equal 15,10, and 5 times the average grain diameter, respectively. A study of the influence of sample size on energy dissipation in random packing of spheres has also confirmed that the REV size is about 15 times the average grain diameter. The heterogeneity of systems was found to have no effect on the REV for the parameters of interest for the narrow range of coefficient of uniformity analyzed in this paper. As the REV approach is commonly applied in both experimental and numerical studies, determining minimum REV size for polydisperse granular packings remains a crucial issue.

关键词： Representative elementary volume Polydisperse packing Discrete element method Sample size effect

Effect of particle polydispersity on micromechanical properties and energy dissipation in granular mixtures

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Particuology 2014年第5期12卷 91-99页

作者： joanna Wiacek Marek Molenda Institute of Agrophysics Polish Academy of SciencesDoswiadczalna 420-290 Lublin 27Poland

A series of numerical tests was conducted to study the micromechanical properties and energy dissipation in polydisperse assemblies of spherical particles subjected to uniaxial compression. In general, distributed particle size assemblies with standard deviations ranging from 0% to 80% of the particle mean diameter were examined. The microscale analyses included the trace of the fabric tensor, magnitude and orien- tation of the contact forces, trace of stress, number of contacts and degree of mobilization of friction in contacts between particles. In polydisperse samples, the average coordination numbers were lower than in monodisperse assemblies, and the mobilization of friction was higher than in monodisperse assemblies due to the non-uniform spatial rearrangement of spheres in the samples and the smaller displacements of the particles. The effect of particle size heterogeneity on both the energy density and energy dissipation in systems was also investigated.

关键词： Polydisperse packing Discrete element method Micromechanics Energy dissipation

Evaluation of zeolite-sand mixtures as reactive materials protecting groundwater at waste disposal sites

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Journal of Environmental Sciences 2013年第9期25卷 1764-1772页

作者： Fronczyk joanna Garbulewski Kazimierz Faculty of Civil and Environmental Engineering Department of Geotechnical Engineering Warsaw University of Life Sciences-SGGW

To recognize properties of a mixture of Vistula sand （medium sand acc. to USCS） with Slovak zeolite as reactive materials suitable for permeable reactive barriers proposed for protection of groundwater environment in vicinity of old landfills comprehensive laboratory investigations were performed. The present study investigates the removal of contaminants specific for landfill leachates onto zeolite-sand mixtures containing 20%, 50% and 80% of zeolite （ZS20, ZS50 and ZS80）. Taking into account the results of batch tests it was concluded that the Langmuir isotherm best fitted the data. It was observed that the presence of ammonium, calcium and magnesium decreases the removal efficiency of copper by 32%. Column tests of contaminant migration through the attenuation zone of the reactive materials were interpreted using the software package CXTFIT, which solves a one-dimensional advection-dispersion equation. Column test results also indicate the strong influence of the presence of interfering substances on copper immobilisation; dynamic sorption capacities decrees twofold. Throughout the landfill leachate flow through ZS80 sample, a constant reduction of NH＋4 （at 100%）, K＋（at 93%） and Fe total （at an average of 86%） were observed. There was no reduction in chemical oxygen demand and biochemical oxygen demand.

关键词： permeable reactive barrier reactive materials sorption criteria contaminants migration zeolite-sand mixture break-through curves

Studies on Effect of Tri（2-hydroxypropyl）, Tri（2-hydroxybutyl） and Tri（hydroxythiodiethylene） Borates on Thermal and Heat Properties of Rigid Polyurethane-Polyisocyanurate Foams

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Chinese Journal of Chemistry 2006年第12期24卷 1796-1799页

作者： CZUPRYNSKI Boguslaw PACIOREK-SADOWSKA joanna LISZKOWSKA joanna Casimir the Great Academy of Bydgoszcz Chodkiewicza str. 30 85-064 Bydgoszcz Poland

Effect of tri（2-hydroxypropyl）, tri（2-hydroxybutyl）and tri（hydroxythiodiethylene） borates （BT2HB, BT2HP and BTHET） on the thermal and heat properties of the rigid polyurethane-polyisocyanurate （PUR-PIR） foams was investigated： Increasing amounts of BT2HB and BT2HP in the foam composition, from 0.05 to 0.4 of chemical equivalent, caused increases in the softening point, the temperature of the first mass loss, the extrapolated tempera- ture of the main mass loss foam and temperature of the highest rate of the mass loss. In the case when BTHTE was added to the foam compositions, the lower increase in the mentioned above characteristic temperatures was observed as compared to those of standard foam （without borate added）.

关键词： rigid PUR-PIR foam heat and thermal resistance thermogravimetric analysis softening point

Life cycle assessment of opencast lignite mining

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International Journal of Coal Science & Technology 2021年第6期8卷 1272-1287页

作者： Lukasz Lelek joanna Kulczycka Mineral and Energy Economy Research Institute Polish Academy of SciencesWybickiego 7A Str.31-261 CracowPoland Faculty of Management AGH University of Science and Technology30-067 CracowPoland

The life cycle phase of fossil fuel extraction is mainly considered in the life cycle assessment(LCA)when evaluating the energy production *** is then only one of many unit processes,which contribute to the blurring of mining-relevant *** are few items in the literature focusing exclusively on the lignite mining phase and analysing the specific mining conditions and associated environmental *** article focuses on the LCA of lignite mining processes on the basis of data coming from a Polish *** technology for opencast lignite mining is noted for its high production efficiency,high level of recovery and lower risk as regards the safety of workers when compared with underground mining ***,the need to remove large amounts of overburden to uncover the deposit contributes to a much greater degradation of the *** the results obtained,several key(hot spot)elements of the lignite mining operations were distinguished for modelling the environmental impact,i.e.:calorific value,the amount of electricity consumption,the manner in which waste and overburden are *** a result there is a high sensitivity of the final indicator to changes in these impacts.

关键词： Life cycle assessment(LCA) Lignite Mining Fossil fuel

Closed-Form Formulae for European Options Under Three-Factor Models

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Communications in Mathematics and Statistics 2020年第4期8卷 379-408页

作者： joanna Goard University of Wollongong WollongongNSWAustrali

In this paper,we derive new closed-form valuations to European options under three-factor hybrid models that include stochastic interest rates and stochastic volatility and incorporate a nonzero covariance structure between *** make novel use of the empirically proven 3/2 stochastic volatility model with a time-dependent drift inwhich we are free to choose the moving reversion *** has been shown bymany authors to empirically outperform other volatility models in maximising model *** also improve the valuation of European options under the Heston volatility and Cox,Ingersoll,Ross interest rate model,recently published in the literature,by replacing open-form infinite series with closed-form analytic *** completeness,we also add a fuller covariance structure in this setting and detail closed-form valuations for *** inclusion of nonzero covariances amongst the factors can significantly improve option pricing by allowing for a wider variety of market *** solutions are derived by firstly formulating the price of a European call option in terms of the corresponding characteristic function of the underlying price and then determining a partial differential equation for the characteristic *** including empirically proven models into our analysis,the options formulae could provide more realistic prices for investors and practitioners.

关键词： European optionvaluation Stochastic volatility Stochastic interest rates Heston model 3/2 model

Carbon Xerogel-supported Iron as a Catalyst in Combustion Synthesis of Carbon Fibrous Nanostructures

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Journal of Materials Science & Technology 2012年第4期28卷 294-302页

作者： Wojciech Kiciński joanna Lasota Institute of Chemistry Military University of Technology Kaliskiego 2 00-908 Warsaw Poland

The catalytically assisted self-propagating high-temperature synthesis of carbon fibrous nanostructures, where the iron-doped colloidal carbon xerogel is proposed as a catalyst system, was examined. The carbon xerogel was prepared through carbonization of an iron doped organic xerogel at temperatures ranging from 600 to 1050℃. The reaction between calcium carbide and hexachloroethane in the presence of sodium azide is exothermic enough to proceed at a high temperature, self-sustaining regime. The combustion reactions of those mixtures enriched with iron-doped carbon xerogels were conducted in a stainless steel reactor---calorimetric bomb under an initial pressure of 1 MPa of argon. Scanning electron microscopy analysis of the combustion products revealed low yield of various type of carbon fibers （presumably nanotubes）, which grew via the tip-growth mechanism. The fibrous nanostructures were found in the vicinity of the spot of ignition, while in the outer and cooler area of the reactor, dusty products with soot-like morphology dominated. No significant correlation between the pyrolysis temperature of the carbon xerogel and the morphology of the obtained carbon fibrous nanostructures was observed.

关键词： Combustion synthesis Carbon xerogel Carbon fibrous nanostructures Carbonnanotubes Scanning electron microscopy