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EN
Porphyrin photosensitizers tend to localize in mitochondria. The depolarization of mitochondrial membrane is one of the early stages of apoptosis and Laser Scanning Fluorescence Microscopy allows to determine changes in transmembrane mitochondrial potential under influence of PDT depending on the kind of photosensitizer (PP(Arg)2, Hp(Arg)2), the energy dose (5, 10, 30 and 50 J/cm2) and time periods (24 and 48 hours after irradiation) in the LNCaP (lymphonodal metastasis of prostate carcinoma, the androgen dependent cell line). Cyototoxicity induced by PP(Arg)2- and Hp(Arg)2-based PDT depending on energy dose and time after irradiation in prostate carcinoma is determined with MTT. Generally, it was shown that lower energy doses induce greater changes in transmembrane mitochondrial potential. Hp(Arg)2-based PDT was more effective causing greater mitochondrial membrane depolarization and cell viability decrease in comparison to PP(Arg)2-mediated PDT (in the case of maximal nontoxic photosensitizer doses used).
EN
Biological studies rely on measurements performed on large populations, which allow the statistic evaluation of gathered data. On the other hand, the need to precisely localize observed processes and the facts occurring in the microscale results in the need of high resolution qualitative imaging. These two approaches are complementary and without anyone of them no valuable experimental data can be gathered from studies of fluorescent dyes. Both approaches are based on common origin of laser-induced fluorescence, but due to the method of analysis they split into the quantitative (laser scanning cytometry) and qualitative (confocal microscopy) fields of research.
EN
Confocal microscopy is commonly used in mineralogy for structural analysis and to investigate the chemical composition of minerals. In our work we performed imaging of structural defects in meteorites i.e. imaging of microstructures, inclusions, fractures and cracks. Information obtained in this way enables better understanding of minerals' origin and evolution. The aim of our work was not concentrated on the deep description of physical processes related to confocal microscope (CSLM) imaging. This paper is limited to the presentation of a few CSLM functions and possibilities, which have practical application in the interpretation of fluorescence microscope imaging of minerals. Confocal microscopy enables identification and preview of localization of selected minerals and therefore can be used to image of the distribution of chemical compounds in minerals.
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EN
We developed a fluorescence confocal microscope equipped with a hemispherical solid immersion lens (SIL) and apply it to study the optical properties of light-harvesting complexes. We demonstrate that the collection efficiency of the SIL-equipped microscope is significantly improved, as is the spatial resolution, which reaches 600 nm. This experimental setup is suitable for detailed studies of physical phenomena in hybrid nanostructures. In particular, we compare the results of fluorescence intensity measurements for a light-harvesting peridinin-chlorophyll-protein (PCP) complex with and without the SIL.
EN
This work presents the characteristics of wood liquefied using different types of solvents in terms of its application for binding particleboards. Standard pine particles from barked wood were used for the liquefaction experiments. The liquefaction reaction was carried out in high temperature conditions using a mixture of solvents from the polyhydroxy alcohol group, including glycerine, ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol. The microstructure of both the liquefied wood and the liquefaction residues was determined by means of optical microscopy analysis. The basic parameters of the adhesive mixture modified with the liquefied wood, such as viscosity, pH and gel time were determined. Particleboards containing liquefied wood were produced. The following physicochemical and mechanical properties of the particleboards were measured: tensile strength, bending strength, modulus of elasticity, and formaldehyde content. The influence of the liquefying agent on the board properties was investigated. In all the tests, a control particleboard, bonded with a urea-formaldehyde adhesive resin with no inclusion of liquefied wood, was used for the purposes of comparison.
EN
We have developed a high density optical data storage by using two-photon absorption process. We have developed a multilayered medium in which photosensitive layers and transparent pressure-sensitive adhesives layer were piled up alternately. We also demonstrate the development of compact high power fiber laser as a light source of high density optical data storage system.
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Content available remote Holographic confocal microscope
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EN
We have developed a new laboratory version of a reflected-light holographic confocal microscope (HCM). The confocal imaging capability with the depth discrimination has been verified by measuring the axial intensity response for a perfect plane mirror. The axial resolution is considerably improved without necessity of high-NA objectives using broadband illumination. The operating principle of the mechanisms employed in a laboratory version of the HCM is outlined
8
Content available remote Surface profilometry by a holographic confocal microscopy
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EN
Confocal imaging by a holographic confocal microscope is based on the real-time incoherent holography. Besides the image amplitude, the image phase is inherently reconstructed. In this paper, we demonstrate that the phase image component can be converted into the height map of the specimen surface, and, in this way, we can measure the surface profile with the precision of several nanometers. The possible ambiguity in the height determination of large height steps is overcome owing to the depth-discrimination property of the microscope. The axial resolution required for this purpose is achieved using broadband illumination.
Open Physics
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2011
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tom 9
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nr 6
1440-1445
EN
The 3D profile surface parameter H q and fractal dimension D were tested as indicators of mechanical properties inferred from fracture surfaces of porous solids. High porous hydrated cement pastes were used as prototypes of porous materials. Both the profile parameter H q and the fractal dimension D showed capability to assess compressive strength from the fracture surfaces of hydrated pastes. From a practical point of view the 3D profile parameter H q seems to be more convenient as an indicator of mechanical properties, as its values suffer much less from statistical scatter than those of fractal dimensions.
10
Content available remote Fluorescent in situ hybridization of mitochondrial DNA and RNA
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EN
To reveal nucleic acid localization in mitochondria, we designed molecular beacon fluorescent probes against: i) the light strand complementary to ND5 mitochondrial DNA (mtDNA) gene (annealing also to corresponding mRNA); ii) displacement (D) loop 7S DNA (annealing also to parallel heavy strand mtDNA and corresponding light strand transcript); iii) the proximal D-loop heavy strand displaced by the light strand promoter minor RNA. Confocal microscopy demonstrated ND5 probe spreading (less for other probes) in mitochondrial reticulum tubules but upon RNase A treatment all probes contoured mtDNA nucleoid localization. DNase I spread the signal over mitochondrial tubules. Future applications are discussed.
EN
The goals of this work are to design and develop a technology for fabrication and study of multifunctional properties of core/shell nanoparticles (NPs) as magnetic/luminescent markers. The new hybrid core/shell Fe₃O₄/Gd₂O₃:1% Er³+, 18% Yb³+, 2.5% Mg²+, x% Nd³+ NPs doped with different concentrations of neodymium ions, where x = 0%, 0.5%, 0.75%, 1%, 2%, 4%, were synthesized by the co-precipitation method. The NPs were characterised using XRD, TEM, SEM, EDX, confocal microscopy and photoluminescence. Fe₃O₄ (core) consists of several 13 nm NPs. The core/shell NPs have sizes from 220 nm to 641 nm. In this latter case, the shell thicknesses were 72, 80, and 121 nm. The upconversion efficiency properties and magnetic properties of the hybrid NPs were investigated. In the core/shell NPs, the addition of Nd³+ quenches the luminescence. The magnetic response of core/shell samples is rather paramagnetic and does not differ significantly from that registered for the shell material alone. For Gd₂O₃:1% Er³+, 18% Yb³+ and Fe₃O₄/Gd₂O₃:1% Er³+, 18% Yb³+, 2.5% Mg²+, 0.5% Nd³+, at 300 K, the values of the magnetization registered at ~ 40 kOe are similar and equal to ~ 5.3 emu·g⁻¹. The survivability of the HeLa tumor cells with the presence of the core/shell NPs was investigated for 24 h. The NPs are non-toxic up to a concentration of 1000 μg·ml⁻¹ and penetrate cells in the process of endocytosis which has been confirmed by confocal microscope studies.
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Content available remote Ocena parametrów krawędzi ciętej masywnych i porowatych stopów metali
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PL
Scharakteryzowano cechy i zakres stosowalności procesów cięcia w odniesieniu do materiałów masywnych i porowatych. Przedstawiono główne aspekty oceny parametrów krawędzi ciętej tworzyw metalicznych i uwarunkowania prawne badania krawędzi ciętych. Przedstawiono opracowaną przez autorów metodykę badania struktury geometrycznej płaszczyzny cięcia kompozytowych pian aluminiowych po cięciu laserowym. Zaproponowano mikroskopię konfokalną jako metodę umożliwiającą badanie powierzchni o dużym udziale nieciągłości spowodowanych porowatością. Scharakteryzowano parametry jakości płaszczyzny cięcia oraz problemy metodyczne i techniczne wynikające z porowatej struktury pian metalicznych, a także obrazy 2D i 3D krawędzi piany aluminiowej po cięciu termicznym laserowym.
EN
The features and scope of the applicability of the cutting processes for massive and porous materials have been characterized. The paper presents the main aspects of the assessment of the cutting edge parameters of metallic materials and the legal conditions of the cutting edges inspection. The study methodology of the cutting plane geometric structure of aluminium composite foam after laser cutting, developed by the authors, has been discussed. Confocal microscopy has been proposed as a method for examining surfaces with a large share of discontinuity caused by porosity. The quality parameters of the cutting plane have been characterized, as well as methodological and technological problems arising from the porous structure of metallic foams and also 2D and 3D image of the aluminium foam edge after thermal laser cutting.
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Purpose: Lubricants prepared with metal oxide nanoparticle additives are found to have better tribological properties. In this work the widely used commercial SN lubricating oil is added with SiO2 nanoparticle and the tribological characteristics are studied. Wear tests were conducted on plain oil and oil with nanosized silica (SiO2) additives using a four ball tribo-tester. Design/methodology/approach: The wear images of the ball specimens were analyzed using confocal microscope to measure the topography of the wear parameters such as wear scar diameter, depth of wear, angle of the wear. Findings: It is found that the gear oil with silica nanoparticles is found to have improved properties. Results show a considerable reduction in the values of wear scar diameter, wear angle and wear depth for the gear oil added with SiO2 nanoparticles of 0.4 wt. %. Originality/value: In the work carried out, a new innovative technological approach to analyze the tribological properties of lubricating oil by finding the wear scar diameter, wear angle and wear depth is reported.
PL
W artykule zaprezentowano wyniki badań struktury geometrycznej powierzchni wewnętrznej aluminiowych tłoczysk pneumatycznych wybieraków stosowanych w automatycznych skrzyniach biegów AS TRONIC MID. Badania powierzchni przeprowadzono przy użyciu mikroskopii konfokalnej, dla różnej wielkości pól pomiarowych, a następnie skonfrontowano je ze sobą. Uzasadniono konieczność definiowania sposobu wykonywania pomiaru podczas podawania wyników, a także stosowania odpowiednich oznaczeń w dokumentacji konstrukcyjnej podczas podawania wymagań dotyczących przestrzennego stanu struktury geometrycznej powierzchni. Przyjęcie odmiennej metodyki badań może spowodować różnice w pomiarach sięgające nawet 100%.
EN
In this paper was presented the results of research on the geometrical structure of the internal surfaces of aluminum pistons of pneumatic selectors used in AS TRONIC MID automatic gearboxes. The studies were carried out using confocal microscopy for different sizes of measuring fields. It was justified to define the way in which the measurement was performed and apply suitable designation in the construction documentation. The results of measurement can be difference of up to 100% by adopting a different research methodology.
19
Content available remote Confocal microscopy description of porosity defects in metallic composite alloys
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EN
Possibilities of confocal microscopy applications for the description of open porosity defects in metallic composite alloys are presented. This article characterizes the method and presents its possible applications by describing a representative area of the examined void.
PL
W pracy przedstawiono możliwości zastosowania mikroskopii konfokalnej do opisu wady porowatość typu otwartego w odlewach z metalowych materiałów kompozytowych. W niniejszym artykule scharakteryzowano metodę i zaprezentowano jej możliwości na przykładzie reprezentatywnego obszaru badanego obiektu (pustki).
20
Content available remote Ocena parametrów krawędzi ciętej masywnych i porowatych stopów metali
75%
PL
Scharakteryzowano cechy i zakres stosowalności procesów cięcia w odniesieniu do materiałów masywnych i porowatych. Przedstawiono główne aspekty oceny parametrów krawędzi ciętej tworzyw metalicznych i uwarunkowania prawne badania krawędzi ciętych. Przedstawiono opracowaną przez autorów metodykę badania struktury geometrycznej płaszczyzny cięcia kompozytowych pian aluminiowych po cięciu laserowym. Zaproponowano mikroskopię konfokalną jako metodę umożliwiającą badanie powierzchni o dużym udziale nieciągłości spowodowanych porowatością. Scharakteryzowano parametry jakości płaszczyzny cięcia oraz problemy metodyczne i techniczne wynikające z porowatej struktury pian metalicznych, a także obraz 2D i 3D krawędzi piany aluminiowej po cięciu termicznym laserowym.
EN
The features and scope of the applicability of the cutting processes for massive and porous materials have been characterized. The paper presents the main aspects of the assessment of the cutting edge parameters of metallic materials and the legal conditions of the cutting edges inspection. The study methodology of the cutting plane geometric structure of aluminium composite foam after laser cutting, developed by the authors, has been discussed. Confocal microscopy has been proposed as a method for examining surfaces with a large share of discontinuity caused by porosity. The quality parameters of the cutting plane have been characterized, as well as methodological and technological problems arising from the porous structure of metallic foams and also 2D and 3D image of the aluminium foam edge after thermal laser cutting.
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