Wyniki wyszukiwania - Biblioteka Nauki

1

Dissecting the pathways of doom - application of spectroscopy in the study of cell death and survival

100%

Godlewski M. , Gorka M. , Gajkowska B. , Wojewodzka U.

Optica Applicata

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2006

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tom Vol. 36, nr 2-3

257-270

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.

2

Cytotoxicity of PP(Arg)2- and Hp(Arg)2-mediated photodynamic therapy and early stage of apoptosis induction in prostate carcinoma in vitro

100%

Nowak-Stępniowska A. , Wiktorska K. , Małecki M. , Romiszewska A. , Padzik-Graczyk A.

Acta Biochimica Polonica

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2011

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tom 58

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nr 4

497-505

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).

3

SIL-based confocal fluorescence microscope for investigating individual nanostructures

100%

Krajnik B. , Schulte T. , Piątkowski D. , Czechowski N. , Hofmann E. , Mackowski S.

Open Physics

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2011

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tom 9

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nr 2

293-299

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.

4

Application of selected agents for wood liquefaction and some properties of particleboards produced with the use of liquefied wood

100%

Janiszewska D. , Frąckowiak I. , Bielejewska N.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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tom vol. 59, nr 197

223--230

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.

5

Holographic confocal microscope

100%

Antosova I. , Harna Z.

Optica Applicata

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2003

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tom Vol. 33, nr 4

605-612

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

6

Surface profilometry by a holographic confocal microscopy

100%

Chmelik R. , Lovicar L. , Harna Z.

Optica Applicata

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2003

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tom Vol. 33, nr 2-3

381-389

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.

7

Femtosecond photonics for three-dimensional high density optical data storage

100%

Kawata Y. , Tsuji M. , Inami W.

Journal of Automation Mobile Robotics and Intelligent Systems

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2009

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tom Vol. 3, No. 4

9-11

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.

8

Roughness and fractality of fracture surfaces as indicators of mechanical quantities of porous solids

88%

Ficker T. , Martišek D.

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.

9

Fluorescent in situ hybridization of mitochondrial DNA and RNA

88%

Alán L. , Zelenka J. , Ježek J. , Dlasková A. , Ježek P.

Acta Biochimica Polonica

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2010

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tom 57

|

nr 4

403-408

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.

10

Analysis of plant tissue images obtained by confocal tandem scanning reflected light microscope

88%

Gancarz M. , Konstankiewicz K. , Pawlak K. , Zdunek A.

International Agrophysics

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2007

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tom 21

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nr 1

11

Immunolocalization of disorganized muscle protein-1 in different life stages of human lymphatic flariid, Brugia malayi

75%

Kushwaha V. , Sahasrabuddhe A. A. , Murthy P. K.

Acta Parasitologica

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2020

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tom 65

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nr 4

12

Analysis of tribological properties of lubricating gear oil with nano silica particles

75%

Prabu K. , Nalini B. , Suresh B. , Sekar M.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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tom Vol. 79, nr 2

59--65

EN

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.

13

Pomiary i analizy powierzchni narzędzi ściernych z wykorzystaniem nowoczesnych technik mikroskopii konfokalnej

75%

Kapłonek W. , Nadolny K. , Valíček J. , Zeleňák M.

Mechanik

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2012

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tom R. 85, nr 8-9CD (NSOŚ)

43--54

14

Zwiększenie odporności na zużycie części w branży motoryzacyjnej : sposoby specyfikacji struktury geometrycznej powierzchni z wykorzystaniem parametru Smr

75%

Dudzińska S. , Grochała D.

Autobusy : technika, eksploatacja, systemy transportowe

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2017

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tom R. 18, nr 7-8

148--152

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.

15

Ocena parametrów krawędzi ciętej masywnych i porowatych stopów metali

75%

Krajewski S. , Nowacki J.

Stal, Metale & Nowe Technologie

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2020

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tom nr 5-6

40--44

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.

16

Confocal microscopy description of porosity defects in metallic composite alloys

75%

Gawdzińska K. , Yatsunenko S. , Przetakiewicz W.

Archives of Foundry Engineering

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2008

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tom Vol. 8, iss. 1 spec.

95--101

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).

17

Ocena parametrów krawędzi ciętej masywnych i porowatych stopów metali

75%

Nowacki J. , Krajewski S.

Stal, Metale & Nowe Technologie

|

2016

|

tom nr 9-10

104--109

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.

18

Measurement of chemical and geometrical surface changes in a wear track by a confocal height sensor and confocal Raman spectroscopy

75%

Winogrodzka A. , Valefi M. , de Rooij M. B. , Schipper D. J.

Archives of Civil and Mechanical Engineering

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2014

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tom Vol. 14, no. 1

1--5

EN

Geometrical and chemical changes in the wear track can cause a drift in friction level. In this paper, chemical and geometrical surface changes in wear tracks are analyzed. For this, a setup with a confocal height sensor was developed to measure the local height changes on the wear track, combined with confocal Raman spectroscopy to determine the chemical changes at the surfaces. Pin-on-disc experiments were performed at room temperature and at elevated temperature (600 °C) to understand the material behavior between mild and severe wear regimes. The wear tracks developing between the two ceramics, alumina (Al2O3) and zirconia (Y-TZP), were analyzed using these techniques. The results of confocal height sensor showed significantly more geometrical changes in surface roughness at 600 C compared to the test conducted at room temperature. The developed roughness in the wear track was approximately 250 times larger at 600 °C due to the higher degradation of the mechanical properties of ceramic. Further, material transfer was observed for the test conducted at 600°C using Raman Spectroscopy. Material transfer at room temperature is difficult to observe because surface changes are less evident in mild wear regimes. The results show that the changes in the micro-geometry of the surface and the chemical compositions of the surface influence the friction level and wear processes. The confocal height sensor and Raman Spectroscopy were used to measure and understand the geometrical and chemical changes occurring on the surface of a wear track during sliding in a single setup.

19

Analysis of multidimensional digital images in fluorescence and confocal microscopy

75%

Dobrucki J. W.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

20

A search for colocalization of serotonin 5-HT2A and 5-HT1A receptors in the rat medial prefrontal and entorhinal cortices-immunohistochemical studies

75%

Wedzony K. , Chocyk A. , Mackowiak M.

Journal of Physiology and Pharmacology

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2008

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tom 59

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nr 2

EN

Recently developed antipsychotic drugs ameliorating the negative symptoms of schizophrenia act not only on dopamine D2 receptors but also on serotonin 2A (5-HT2A) and 1A (5-HT1A) receptors in specific regions of the cerebral cortex. Since it is not yet known whether serotonin 5-HT1A and 5-HT2A receptors coexist in the same population of neurons in the cortex, the present study investigated their colocalization in the rat medial prefrontal (MPC) and entorhinal (EC) cortices. Using antibodies that recognize epitopes specific to the serotonin 5-HT2A or 5-HT1A receptors, studies employing confocal microscopy have shown that in the MPC 5-HT2A receptors are preferentially, if not exclusively, present on the pyramidal neurons and that 5-HT1A-immunopositive material is present in the axonal hillocks and, to lower extend, in cytoplasm of presumably pyramidal cell bodies. With the regard of labeling of active receptors (i.e. present in shafts and axonal hillocks) we found that about 38% of neurons positive for the presence of serotonin 5-HT2A receptors, are also positive for serotonin 5-HT1A receptors in the MPC. In the EC, only 22% of serotonin 5-HT2A-positive neurons were positive for serotonin 5-HT1A receptor-immunoreactivity. In the respect of cytoplasmatic serotonin 5-HT1A receptor-immunoreactivity (possibly inactive receptors), 65% and 73% of serotonin 5-HT2A receptor-positive neurons were colocalized with serotonin 5-HT1A receptors in the MPC and EC, respectively. Data obtained on serotonin 5-HT2A and 5-HT1A receptor localization provide anatomical grounds for at least three distinct populations of pyramidal neurons, one governed only by 5-HT2A, one only by 5-HT1A and one by both types of serotonin receptors.