Publications by authors named "Agnieszka Wilk"

Concurrent radiochemotherapy (RCHT) has been the standard treatment for locally advanced cervical cancer since 1999. During this 20-year period, both diagnostic and radiotherapy techniques have developed, such as positron emission tomography (PET) or brachytherapy (BT) planning. The aim of the study was to assess the relationships between prognostic factors and the results of treatment in patients with advanced cervical cancer independent of these changes.

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The Pr-doped solid solutions from (Ba,Ca)(Ti,Zr)O (BCTZO) system were successfully synthesized using an efficient and low-energy consuming route-the Pechini method combined with the sintering at relatively low temperature (1450 °C). The obtained materials were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dielectric properties were systematically studied.

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The presented work concerns the development and investigation of three different grades of ZrO materials containing AlO particles (ATZ-Alumina Toughened Zirconia ceramics with 2.3-20 vol.% of alumina).

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There is a strong need in the industry to develop lead-free piezoelectrics for sensors and actuators. Although these materials have become an important component of many electronic devices, it is very important for the industry to decarbonise ceramic technology, especially through the introduction of modern sintering technologies. Among the many piezoelectric compounds available, Calcium Barium Titanate (BCT) have been widely investigated because of its similar performance to lead-containing Lead Titanate Zirconate (PZT).

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The myristoylpalmitoylphosphatidylcholine (MPPC) bilayer membrane shows a complicated temperature-pressure phase diagram. The large portion of the lamellar gel (L(β)'), ripple gel (P(β)'), and pressure-induced gel (L(β)I) phases exist as metastable phases due to the extremely stable subgel (L(c)) phase. The stable L(c) phase enables us to examine the properties of the L(c) phase.

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We present a scaling formula for size-dependent viscosity coefficients for proteins, polymers, and fluorescent dyes diffusing in complex liquids. The formula was used to analyze the mobilities of probes of different sizes in HeLa and Swiss 3T3 mammalian cells. This analysis unveils in the cytoplasm two length scales: (i) the correlation length ξ (approximately 5 nm in HeLa and 7 nm in Swiss 3T3 cells) and (ii) the limiting length scale that marks the crossover between nano- and macroscale viscosity (approximately 86 nm in HeLa and 30 nm in Swiss 3T3 cells).

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The phase transitions of dibehenoylphosphatidylcholine (C22PC) bilayer membrane were observed by differential scanning calorimetry under atmospheric pressure and light-transmittance measurements under high pressure. The constructed temperature-pressure phase diagram suggests that the gel phase at low temperatures is the interdigitated gel phase. To confirm the phase state, we performed small-angle neutron scattering and fluorescence measurements using a polarity-sensitive probe Prodan for the C22PC bilayer membrane under atmospheric pressure.

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The hexaethylene glycol monododecyl ether (C(12)E(6)) micelles at concentrations up to 10% have been studied in their isotropic phase (10-48 degrees C) by means of small angle neutron scattering (SANS) and photon correlation spectroscopy (PCS). The SANS data obtained at low temperatures could be unequivocally interpreted as a result of scattering from a suspension of compact globular micelles with the shape of a triaxial ellipsoid or a short end-capped elliptical rod. Different models have been applied to analyze the SANS data obtained at higher temperatures: (i) elongated rod-like micelles with purely sterical interactions, (ii) compact globular micelles with a weak attractive potential, and (iii) globular micelles influenced by the critical phenomena in the whole temperature range studied.

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We measured the viscosity of poly(ethylene glycol) (PEG 6000, 12,000, 20,000) in water using capillary electrophoresis and fluorescence correlation spectroscopy with nanoscopic probes of different diameters (from 1.7 to 114 nm). For a probe of diameter smaller than the radius of gyration of PEG (e.

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We report on the electrophoretic mobility and on the thermal diffusion of lysozyme proteins dissolved in aqueous solutions of a nonionic surfactant (C12E6) at a wide range of concentrations of the surfactant (0-20% by weight). We want to estimate the influence of a dense network of elongated micelles of C12E6 on the effective charge of the proteins as observed in the capillary electrophoresis experiments. The possible mechanism leading to the change in the effective charge of protein could involve the deformation of the cloud of counterions around the protein when it squeezes through the narrow (of the order of a protein diameter) aqueous channels formed in the solution of elongated micelles.

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Although water is the chief component of living cells, food, and personal care products, the supramolecular components make their viscosity larger than that of water by several orders of magnitude. Using fluorescence correlation spectroscopy (FCS), photon correlation spectroscopy (PCS), NMR, and rheology data, we show how the viscosity changes from the value for water at the molecular scale to the large macroviscosity. We determined the viscosity experienced by nanoprobes (of sizes from 0.

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The effects of embedding up to 60 mol% of alpha-tocopherol (alpha-Toc) on the morphology and structure of the egg phosphatidylcholine (PC) membrane were studied using spectroscopic techniques. The resulting vesicles were subjected to turbidometric and dynamic light scattering measurements to evaluate their size distribution. The alpha-Toc intrinsic fluorescence and its quenching was used to estimate the tocopherol position in the membrane.

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We measured the form factor of bottle-brush macromolecules under good solvent conditions with small-angle neutron scattering and static light scattering. The systems under investigation are brushes, synthesized via the grafting-from route, built from a poly(alkyl methacrylate) backbone to which poly(n-butyl acrylate) side chains are densely grafted. The aim of our work is to study how the systematic variation of structural parameters such as the side chain length and backbone length change the conformation of the polymer brushes in solution.

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