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Wyświetlanie 1-3 z 3
Tytuł:
Odbiór bodźców środowiskowych przez glony Characeae sygnalizowany za pomocą ultrasłabej luminescencji
Reception of environmental stimuli by Characeae algae manifested by ultraweak luminescence
Autorzy:
Jaśkowska, A.
Dudziak, A.
Borc, R
Powiązania:
https://bibliotekanauki.pl/articles/1819387.pdf
Data publikacji:
2012
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
photon emission
heavy metals
inhibition
Opis:
Protecting the environment requires ensuring such conditions that organisms living in it did not suffer permanent damage to their structures and life functions. This also applies to algae living in the aquatic environment. Some species of water flora especially quickly react to negative stimuli arriving from the environment. Their reactions to experienced stress may be a subtle criterion for assessing the condition of aquatic environment. To this kind of plants belong Chara, which are bioindicators of water quality. Their response to applied environmental stimuli is rapid changes of the electrical parameters of the cell membrane. Our research shows that there is also a change in the intensity of ultraweak luminescence (UWL) generated by these plants. UWL is a phenomenon that continuously accompanies processes occurring in living cells and its intensity is less than the threshold sensitivity of the human eye. The method of measurement of this little known way of Chara's response to environmental stimuli has the advantage that it is completely non-invasive for the test material. Non-invasiveness is due to the fact that the radiation emitted from the samples is measured outside the cell membrane separating the living matter from the surrounding environment. In our study, after exposure to a selected stimulus, three types of responses of plant cells were observed: 1) - after a temporary increase of UWL, there is a return to the level of light corresponding to undisturbed homeostasis (e.g. when ascorbic acid is added to the environment); 2) - after a temporary increase in the UWL, the emission of photons slightly falls and stabilizes at a new higher level of illumination (when the stress stimulus is e.g. lead acetate, the emission intensity is 2.2 times larger than in the beginning); 3) - after a sudden and significant increase of UWL, the high emission level is maintained for many hours (e.g. after adding sucrose follows a 20-fold increase of UWL). UWL curves obtained in our experiments correlate with the changes of entropy corresponding to the disturbance of homeostasis in individual cases, depending on the applied stimulus. Respectively: for 1) - an increase of entropy is temporary and is followed by a return to values before the application of the stimulus, 2) - a lasting change occurs, which consists in an increase of entropy to a new fixed level, 3) - change in entropy is so large that its value exceeds the so-called point of no return, which means that the disorder of homeostasis leads to cell death. The application of luminescence imaging technique Single Photon Counting Imaging (SPCI) to the test cells have revealed that the emission of photons from different parts of the plant has a different intensity. When the plant suffered mechanical damage by cutting pseudoleaves, the emission from the damaged sites increased dramatically. This observation allows the damage to be located. Thanks to SPCI technique, it is also possible to track over time any repair processes. The clear differentiation of UWL kinetics leads to the conclusion that monitoring its intensity can be a good research tool in environmental protection. It makes it possible to determine whether chemicals found in the aquatic environment are harmful to a given species of plants. It can be also assessed whether the degree of the harm threatens the entire population with extinction. Thus, the presented method can be used as an ecotoxicity test.
Źródło:
Rocznik Ochrona Środowiska; 2012, Tom 14; 380-392
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PET and SPECT imaging as a solid guide to detect and discriminate atypical phenotypes of neurodegenerative disorders
Autorzy:
Ruffini, Livia
Zilioli, Alessandro
Cervati, Veronica
Lauretani, Fulvio
Misirocchi, Francesco
Maggio, Marcello
Migliari, Silvia
Graziani, Tiziano
Cidda, Carla
Baldari, Giorgio
Spallazzi, Marco
Scarlattei, Maura
Powiązania:
https://bibliotekanauki.pl/articles/40521373.pdf
Data publikacji:
2024-03-30
Wydawca:
Uniwersytet Rzeszowski. Wydawnictwo Uniwersytetu Rzeszowskiego
Tematy:
atypical phenotypes
neurodegenerative diseases
positron emission tomography
single photon emission computed tomography
Opis:
Introduction and aim. Atypical or mixed presentations of neurodegenerative disorders may postpone or confound the final diagnosis. Molecular imaging with positron emission tomography (PET) and single photon emission computed tomography (SPECT) radioligands provide target-specific information and may anticipate the diagnosis by “in vivo” detection of the neuropathological substrate, as Aβ deposition, nigrostriatal dopaminergic depletion or tau inclusions. This concise review will discuss the potential of PET and SPECT imaging as a solid guide to better characterize atypical phenotypes of neurodegeneration in the clinical routine, with the potential to drive personalized interventions, improve cohort uniformity for clinical trials, and serve as biomarkers for targeted molecular therapies. Material and methods. Literature search was performed focusing on the role of PET and SPECT imaging in assessing atypical phenotypes of neurodegeneration, using the electronic source of database PubMed/MEDLINE and the web-based search engines Google, Google Scholar. Analysis of the literature. New disease-modifying drugs may increase their effect with early initiation, which is especially important in working persons and younger subjects presenting atypical symptoms. In older individuals, the coexistence of neurodegeneration, age-related changes, cerebrovascular lesions, or depression makes challenging a definitive diagnosis. Quantitative tools able to measure tracer distribution increase the accuracy of molecular neuroimaging creating topographic maps that compare subject’s data with healthy controls databases. Conclusion. Atypical phenotypes may be associated with quantitative key-pattern allowing a more precise and early diagnosis of the neurodegenerative disorder. Finally, quantitative assessment of the pathological substrates allows us to track the disease process and measure treatment response.
Źródło:
European Journal of Clinical and Experimental Medicine; 2024, 22, 1; 201-221
2544-2406
2544-1361
Pojawia się w:
European Journal of Clinical and Experimental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Związki kompleksowe na bazie Gd(III), W(IV), Mn(II), Eu(III) i 99mTc wykorzystywane w diagnostyce medycznej
Complex compounds based on Gd(III), W(IV), Mn(II), Eu(III) and 99mTc used in medical diagnostics
Autorzy:
Pobłocki, Kacper
Drzeżdżon, Joanna
Jacewicz, Dagmara Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/2200431.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
obrazowanie medyczne
związki kompleksowe
magnetyczny rezonans jądrowy
tomografia emisyjna pojedynczego fotonu
rentgenografia
obrazowanie optyczne
medical imaging
complex compounds
magnetic resonance imaging
single-photon emission computed tomography
rentgenography
optical imaging
Opis:
Recently, hospitals have undergone major changes. Minimally invasive surgery is becoming more common, and numerous innovations are emerging, such as interventional radiology (IVR) and hybrid surgery. In order to keep pace with changes in this extremely dynamic field, scientist keep working on the development of imaging technology and the improvement of image display devices and new compounds acting as contrast agent (CA). In medicine, metals are used for diagnostic and therapeutic purposes. Inorganic elements are increasingly used as contrast agents in medical imaging due to their unique physicochemical properties. In this review, we would like to focus on the latest literature reports that contain information on Gd(III), W(IV), Mn(II), Eu(III) and 99mTc used in medical diagnostics.
Źródło:
Wiadomości Chemiczne; 2022, 76, 9-10; 803--823
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

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