Autor: Lewicka, S - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Electron-Positron Annihilation in Ultra-Strong Magnetic Fields. Comparison of One- and Two-Photon Annihilation at Middly Relativistic Regime
Autorzy:: Lewicka, S.
Powiązania:: https://bibliotekanauki.pl/articles/1336207.pdf
Data publikacji:: 2014-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 11.10.Ef
12.20.Ds
95.60.-k
97.60.Gb
Opis:: We consider the one- and two-photon $e^+e^-$ annihilation processes in an ultra-strong magnetic field, at middly relativistic regime. Such conditions are reached in neutron stars and especially in magnetars, where electrons and positrons flow within the magnetar corona with average momenta of the order of p~$m_0c$, where $m_0$ - electron mass, c - light speed. We pay special attention to the ratio of the total annihilation rates of both processes. The well-known result is that in the limit p → 0 and for magnetic induction above the critical Schwinger value $B_0$=4.41× $10^9$ T, one-photon annihilation dominates over the two-photon process. Results presented in this article verify the current knowledge about this ratio in magnetars; the calculations indicate that for particles moving with middly relativistic momenta both processes can be equally important.
Źródło:: Acta Physica Polonica A; 2014, 125, 3; 688-690
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Central limit theorem and the short-term temperature response of coleoptile and hypocotyl elongation growth
Autorzy:: Lewicka, S
Pietruszka, M.
Powiązania:: https://bibliotekanauki.pl/articles/56965.pdf
Data publikacji:: 2008
Wydawca:: Polskie Towarzystwo Botaniczne
Tematy:: temperature
coleoptile
hypocotyl
elongation growth
temperature response
plant biology
Opis:: In this contribution we deal with a new mathematical description of the response of short-term coleoptile/hypocotyl expansion growth to temperature. Although the interest of both the bio-mechanical basis of elongation growth and temperature responses has been studied in plant biology and biophysics for a long time, yet the question of the mode of actions of temperature is very relevant and still open. Here we introduce a simple idea that the normal distribution, due to the central limit theorem (CLT), is able to report on temperature-dependent elongation growth. The numerical fittings for temperature affected growth are in good agreement with empirical data. We suggest that the observation concerning a crossover effect occurring in temperature driven elongation together with CLT leads to the formulation of a hypothesis about the possible universal character of such a description, supposedly for many plant species and families. We conclude with the statement that properly constructed equations of temperature affected growth, should possibly include a specific term proportional to exp[-((T-T0)/T0)2] with T0 corresponding to the temperature of the optimum growth.
Źródło:: Acta Societatis Botanicorum Poloniae; 2008, 77, 4; 289-292
0001-6977
2083-9480
Pojawia się w:: Acta Societatis Botanicorum Poloniae
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Mathematical model for tissue stresses in growing plant cells and organs
Autorzy:: Lewicka, S
Pietruszka, M.
Powiązania:: https://bibliotekanauki.pl/articles/57317.pdf
Data publikacji:: 2009
Wydawca:: Polskie Towarzystwo Botaniczne
Tematy:: growing plant
plant cell
mathematical model
tissue stress
equilibrium equation
plant organ
Opis:: In this study we propose a simple mathematical model based on the equilibrium equation for the materials deformed elastically. Owing to the turgor pressure of the cells, the peripheral walls of the outer tissue are under tension, while the extensible inner tissue is under compression. This well known properties of growing multicellular plant organs can be derived from the equation for equilibrium. The analytic solutions may serve as a good starting point for modeling the growth of a single plant cell or an organ.
Źródło:: Acta Societatis Botanicorum Poloniae; 2009, 78, 1; 19-23
0001-6977
2083-9480
Pojawia się w:: Acta Societatis Botanicorum Poloniae
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Thermodynamics of irreversible plant cell growth
Autorzy:: Pietruszka, M
Lewicka, S.
Pazurkiewicz-Kocot, K.
Powiązania:: https://bibliotekanauki.pl/articles/58662.pdf
Data publikacji:: 2006
Wydawca:: Polskie Towarzystwo Botaniczne
Tematy:: thermodynamics
irreversible process
plant cell
plant growth
cell wall
yielding
growth stimulator
growth inhibitor
modified growth equation
Opis:: The time-irreversible cell enlargement of plant cells at a constant temperature results from two independent physical processes, e.g. water absorption and cell wall yielding. In such a model cell growth starts with reduction in wall stress because of irreversible extension of the wall. The water absorption and physical expansion are spontaneous consequences of this initial modification of the cell wall (the juvenile cell vacuolate, takes up water and expands). In this model the irreversible aspect of growth arises from the extension of the cell wall. Such theory expressed quantitatively by time-dependent growth equation was elaborated by Lockhart in the 60's.The growth equation omit however a very important factor, namely the environmental temperature at which the plant cells grow. In this paper we put forward a simple phenomenological model which introduces into the growth equation the notion of temperature. Moreover, we introduce into the modified growth equation the possible influence of external growth stimulator or inhibitor (phytohormones or abiotic factors). In the presence of such external perturbations two possible theoretical solutions have been found: the linear reaction to the application of growth hormones/abiotic factors and the non-linear one. Both solutions reflect and predict two different experimental conditions, respectively (growth at constant or increasing concentration of stimulator/inhibitor). The non-linear solution reflects a common situation interesting from an environmental pollution point of view e.g. the influence of increasing (with time) concentration of toxins on plant growth. Having obtained temperature modified growth equations we can draw further qualitative and, especially, quantitative conclusions about the mechanical properties of the cell wall itself. This also concerns a new and interesting result obtained in our model: We have calculated the magnitude of the cell wall yielding coefficient (T) [m3 J-1•s-1] in function of temperature which has acquired reasonable numerical value throughout.
Źródło:: Acta Societatis Botanicorum Poloniae; 2006, 75, 3; 183-190
0001-6977
2083-9480
Pojawia się w:: Acta Societatis Botanicorum Poloniae
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Tradycyjne i nowe kierunki biotechnologicznego wykorzystania drożdży z rodzaju Rhodotorula
Traditional and new directions in biotechnological applications of yeast species of the genus Rhodotorula
Autorzy:: Lewicka, A.
Blazejak, S.
Migdal, M.
Powiązania:: https://bibliotekanauki.pl/articles/827207.pdf
Data publikacji:: 2009
Wydawca:: Polskie Towarzystwo Technologów Żywności
Tematy:: odpady
Rhodotorula
adsorpcja
biodegradacja
biomasa
biopaliwa
biotechnologia
drozdze
egzopolisacharydy
enzymy
karotenoidy
wykorzystanie
Opis:: Drożdże z rodzaju Rhodotorula występują powszechnie w środowisku. Do niedawna postrzegane były głównie jako psujące lub zanieczyszczające żywność saprofity. Jednak odkrycie przez naukowców wielu nowych możliwości ich wykorzystania pozwala sądzić, że mogą stać się w przyszłości znaczącą grupą drobnoustrojów przemysłowych. W niniejszym opracowaniu przedstawiono niektóre kierunki zastosowania drożdży z rodzaju Rhodotorula. Karotenoidy, egzopolisacharydy oraz enzymy produkowane przez biomasę komórkową tych drożdży mogą być wykorzystywane w wielu branżach przemysłu. Równie ważnym aspektem, uwzględnianym przy ocenie przydatności drożdży, jest wykorzystanie ich biomasy komórkowej w procesach wiązania jonów metali bądź biodegradacji odpadów.
The yeast species of the genus Rhodotorula are ubiquitous in the human environment. Until recently, they have been mainly perceived as saprophytes, which spoil or contaminate food products. However, owing to many new options discovered by scientists of using them, they could be supposed to become a significant group of micro-organisms in the future. In this paper, some directions of using yeast of the genus Rhodotorula are presented. Carotenoids, exopolysaccharides, and enzymes produced by the biomass of Rhodotorula strain can be applied in many industrial fields. While assessing the usefulness of yeast, another more important aspect is considered, namely, the utilization of their cell biomass in the processes of binding metal ions or in biodegradation of waste/refuse.
Źródło:: Żywność Nauka Technologia Jakość; 2009, 16, 3
1425-6959
Pojawia się w:: Żywność Nauka Technologia Jakość
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Impact of Hydrotechnical Structures on Forming the Tombolo Oceanographic Phenomenon in Kołobrzeg and Sopot
Autorzy:: Specht, C.
Lewicka, O.
Specht, M.
Zblewski, S.
Powiązania:: https://bibliotekanauki.pl/articles/2063963.pdf
Data publikacji:: 2021
Wydawca:: Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:: oceanographic phenomenon
hydrotechnical structures
Tombolo
Sopot
Port of Kolobrzeg
sea level
Polish Ports
Opis:: The process of global sea level rise is causing several significant changes in the coastal zone. Sea level rise and the frequency, strength and duration of storms are also occurring on the Polish coast. As a result, coastal protection measures, such as man-made engineering structure, are necessary. These engineering structures affect (among others) the marine ecosystem in different ways. Although the presence of such engineering structures can cause changes in the bathymetry of waterbody and the transport of sediments along the basin, it also slows down the erosion of the shoreline. For this reason, comprehensive knowledge of natural conditions, including dynamic and variable factors, is essential in the construction of a hydro-engineering structures. The correct determination of the environmental conditions helps to minimize environmental damage. Prior to interventions on the coast, the issues addressed in the paper should be analysed and studied. In this paper, the influence of shoreline structures on the main factors responsible for the development of tombolo phenomenon is discussed. In addition, the lithological diversity of surface sediments on which the rate of coastal erosion depends, is also discussed. An important element of the work is the descriptions of tombolo in Poland. They contain information on the causes of the phenomenon, as well as about the negative consequences of a disturbance of the hydrodynamic dynamics caused by the structure.
Źródło:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 3; 687--694
2083-6473
2083-6481
Pojawia się w:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Comparative analysis of unmanned aerial vehicles used in photogrammetric surveys
Autorzy:: Specht, M.
Widźgowski, S.
Stateczny, A.
Specht, C.
Lewicka, O.
Powiązania:: https://bibliotekanauki.pl/articles/24201468.pdf
Data publikacji:: 2023
Wydawca:: Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:: unmanned aerial vehicle
unmanned vehicles
photogrammetry
drone
inertial navigation system
hydrography
Global Navigation Satellite System
LiDAR
Opis:: There are many manufacturers on the market offering various types of Unmanned Aerial Vehicles (UAV). The multitude of drones available on the market means that the choice of a UAV for a specific application appears to be a decision problem to be solved. The aim of this article is a comparative analysis of drones used in photogrammetric surveys. The criteria for evaluating the UAVs were: availability and product support, payload (min. 5 kg), price (PLN 100,000), as well as space available for measurement modules. These are the requirements that must be met for the implementation of the INNOBAT project, the aim of which is to develop an integrated system using autonomous unmanned aerial and surface vehicles, intended for bathymetric monitoring in the coastal zone. The comparative analysis of drones was based on 27 companies producing UAV. Based on the analysis, 6 drones that met the project requirements were selected. They were: Aurelia X6 Pro, Aurelia X8 Standard LE, DroneHexa AG, FOX-C8 XT, Hercules 10 and Zoe X4. Selected UAVs differ from each other, among others, in the number of rotors, flight duration and resistance to weather conditions. Individual characteristics of drones may have a different rank depending on their application, therefore the selection of UAVs should be made after prioritisation criteria of a given project.
Źródło:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2023, 17, 2; 433--443
2083-6473
2083-6481
Pojawia się w:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: The role of Chromium III in the organism and its possible use in diabetes and obesity treatment
Autorzy:: Lewicki, S.
Zdanowski, R.
Krzyzowska, M
Lewicka, A.
Debski, B.
Niemcewicz, M.
Goniewicz, M.
Powiązania:: https://bibliotekanauki.pl/articles/52045.pdf
Data publikacji:: 2014
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2014, 21, 2
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki