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3. Black leaf-clips increased minimum fluorescence emission in clipped leaves exposed to high solar radiation during dark adaptation

Creator:
Giorio, P.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, leaf-clip effect, pepper, photochemical efficiency, radiation, temperature, and tomato
Language:
Multiple languages
Description:
Tomato and pepper leaves were clipped with black leaf clips for dark adaptation under solar radiation in the late spring or early summer 2010 in southern Italy. The leaves showed highly variable maximum PSII quantum yield (Fv/Fm = 0.026-0.802) using a continuous-excitation fluorometer Pocket PEA. These results were confirmed using the modulated fluorometer FMS1 on tomato leaves in mid summer, with Fv/Fm as low as 0.222 ± 0.277 due to nearly equal minimum (F0) and maximum (Fm) fluorescence emission. A significant clip effect on Fv/Fm occurred after only 12 (tomato) or 25 (pepper) min. Increasing the leaf temperature from 25 to 50°C reportedly induced an F0 increase and Fm decrease so that Fv/Fm approached zero. The hypothesis that black leaf clips overheated under intense solar irradiance was verified by shrouding the clipped leaves with aluminum foil. In clipped leaves of pepper, Fv/Fm with the black clip/Pocket-PEA was 0.769 ± 0.025 (shrouded) and as low as 0.271 ± 0.163 (nonshrouded), the latter showing a double F0 and 32% lower Fm. An 8% clip effect on Fv/Fm was observed with the white clip/FMS1. To avoid the clip effect in high irradiance environments, Fv/Fm measurements with black clip/Pocket PEA system required leaf dark adaptation with radiation-reflecting shrouds. It would be useful if manufacturing companies could develop better radiation-reflecting leaf clips for the Pocket PEA fluorometer. and P. Giorio.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. George F. Smoot: životopis

Creator:
Smoot, George F. and Gregora, Ivan
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Smoot, George, 1945-, 20.-21. století, fyzici, záření, ceny a vyznamenání, Nobelova cena (ocenění), physicists, radiation, awards, Nobel Prizes, Spojené státy americké, United States, 6, and 53
Language:
Czech and English
Description:
Získat Nobelovu cenu je událost, která změní život. Bod zlomu. Mnoho lidí chce vědět, jak toho laureát dosáhl, a také se po něm žádá, aby dodal svůj životopis. To všechno a události provázející udělení Nobelovy ceny způsobí, že se každý z nás zamyslí nad svým životem, zavzpomíná a pokusí se vystihnout všechny události, které ho dovedly až do přítomnosti., George F. Smoot ; přeložil Ivan Gregora., and přeloženo z angličtiny
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Immunomodulation in insects post-treatment with abiotic agents: a review

Creator:
Shaurub, El-Sayed H.
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Insects, insecticides, chitin synthesis inhibitors, juvenile hormone analogues, inert particles, antibiotics, heavy metals, radiation, immunomodulation, 2, and 59
Language:
English
Description:
The effects of different abiotic agents that may modulate the activity of an insect’s immune system are reviewed. These agents include insecticides, chitin synthesis inhibitors, juvenile hormone analogues, inert particles, antibiotics, heavy metals, radiation and miscellaneous substances. The significance of studying immunomodulation in insects treated with abiotic agents in relation to both insect control and insect-borne parasitic diseases and the link between immunomodulation in insects post-treatment with both abiotic and biotic agents are discussed., El-Sayed H. Shaurub., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

6. Od Lemaîtra k reliktnímu záření a Jamesi Peeblesovi

Creator:
Chýla, Jiří
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fyzikální kosmologie, záření, physical cosmology, radiation, 6, and 53
Language:
Czech
Description:
Half of this year‘s Nobel Prize in Physics was awarded to American cosmologist James Peebles "for theoretical discoveries in physical cosmology". In this article we describe the emergence of the BigBang model of the Universe, recall the people who made decisive contributions to its formulation, emphasize the crucial importance of the discovery of Cosmic Microwave Background radiation, and outline the contribution James Peebles made for the understanding of our Universe. and Jiří Chýla.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Physiological responses of Pterocladiella capillacea (Rhodophyta, Gelidiales) under two light intensities

Creator:
Harb, T. B., Nardelli, A., and Chow, F.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
řasy, pigmenty, produktivita, záření, Algae, pigments, productivity, radiation, chlorophyll fluorescence, growth rate, 2, and 581
Language:
Multiple languages
Description:
Macroalgae must be able to survive in conditions of different light intensities with no damage to their physiological performance or vital processes. Irradiance can stimulate the biosynthesis of certain photoprotective compounds of biotechnological interest, such as pigments and proteins. Pterocladiella capillacea is a shade-grown alga, which play a role key in the balance of marine ecosystems. In addition, it is considered one of the best sources of bacteriological agar and agarose with a wide pharmacological potential. In order to evaluate the photosensitivity in P. capillacea under 60 (control) and moderate light intensity of 300 μmol(photon) m-2 s-1, photosynthetic performance and chemical composition were assessed. P. capillacea showed photosensitivity without evidence of photodamage. The results indicate the possibility to increase a growth rate and probably infer productivity in long-term cultivation by stimulation at moderate light intensity. Increasing photosynthetic pigment and protein contents were also observed under medium light, an interesting result for functional ingredient approaches., T. B. Harb, A. Nardelli, F. Chow., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Psychologické souvislosti fyzikálních a fyziologických determinant výkonnosti člověka v kosmu

Creator:
Iva Šolcová
Format:
print
Type:
article, přehledové studie, model:article, and TEXT
Subject:
Psychologie, psychologie, psychology, kosmický let, mikrogravitace, radiace, cirkadiánní rytmy, psychická adaptace, spaceflight, microgravity, radiation, circadian rhythms, psychological adaptation, 17, and 159.9
Language:
Czech
Description:
Článek se zabývá hlavními fyzikálními a fyziologickými determinantami výkonnosti člověka v kosmu a zároveň poukazuje na doposud méně reflektované psychické souvislosti pobytu jedince v tomto extrémním prostředí. Největší pozornost věnuje problematice mikrogravitace, radiace a cirkadiánních rytmů s důrazem na adaptační změny nejen ve fyziologických a psychofyziologických, ale především v psychických procesech. Zaobírá se otázkou pozměněné kvality zpracovávaných informací v prostředí mikrogravitace, a izolace od běžných podnětů a ukazatelů a navozuje otázku dostupnosti a adekvátnosti signálů nejenom pro kognitivní, ale i afektivní a konativní procesy. Autorka soudí, že vedle fyziologické a psychofyziologické adaptace na kosmické prostředí nutně dochází i k adaptaci psychické, respektive k adaptaci psychických procesů. Stať dospívá k závěru, že k plnějšímu pochopení adaptace kognitivních, afektivních a konativních procesů je potřeba především hloubkových kvalitativních šetření průběhu psychické adaptace jedinců pobývajících v kosmu., This paper deals with the main physical and physiological determinants of human performance during a spaceflight and also addresses so far insufficiently discussed psychological context of being in this extreme environment. The greatest attention is paid to the issue of microgravity, radiation and circadian rhythms, with emphasis on the adaptive changes in physiological and psycho-physiological processes. The study explores the issue of data acquisition and the quality of information processing under the condition of isolation and confinement from natural stimuli and indicators. In this way, the paper further deals with the signals available to crew members about the changes in their cognitive, affective and motivational processes. The paper claims that besides the physiological and psycho-physiological adaptation to the space environment, psychological adaptation necessarily goes on at the same time It is concluded that the in-depth qualitative investigation of the psychological adaptation could provide a more complete understanding of the accommodation of cognitive, affective and motivational processes during spaceflights., Iva Poláčková Šolcová., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

9. Schistosoma mansoni: the presence of schistosomule-like characteristics in irradiated cercariae

Creator:
Yssel, E. and Wolmarans, C.T.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Schistosoma monsoni, cercariae, and radiation
Language:
English
Description:
Schistosoma monsoni (Puerto Rican strain) cercariae were exposed to 10, 20, 50, 100, 200, 300, 400 and 500 krad gamma radiation from “Co gamma source. From 10-100 krad irradiation no differences could be found in the behaviour of the cercariae when compared to the controls. From 200-500 krad there was an increase in mortality as well as in the number of cercariae that shed their tails. The Con A binding studies also performed on cercariae radiated with up to 100 krad indicate a direct relationship between the number of cercariae that bind Con A and radiation dose. All live cercarial heads collected after radiation also bound Con A. It thus seems possible that irradiation may act as a stimulus for cercariae to transform to schistosomulae.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

10. Vilém Santholzer: vědec a avantgardista mezi krásou stroje a záření

Creator:
Vítů, Viktorie
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Vilém Santholzer, radiation, art, and photo
Language:
Czech
Description:
Vilém Santholzer byl český radiolog, který v druhé polovině dvacátých let na stránkách avantgardních periodik publikoval ke třem desítkám článků a několik vlastních fotografií radiového záření. Článek sleduje tuto jeho aktivitu a zasazuje ji do kontextu zájmu evropské avantgardy o strojovou estetiku na jedné straně a vědeckou fotografii na straně druhé. Ukazuje, že pro Santholzera je krása vždy přímým důsledek jiných vlastností objektu spojených s pravdou: stroje jsou podle něho krásné, jsou-li účelné, fotografie, jsou-li autentické. Zatímco jeho úvahy věnované strojové estetice můžeme dát do souvislostí s myšlenkami ruského konstruktivismu, Le Corbusiera, Karla Teiga či Wernera Graeffa, v případě jeho fotografií lze hledat paralely u autorů tematizujících možnosti fotografie zviditelnit neviditelné, tedy především u László Mohly-Nagye a opět u Karla Teiga. Zvláštním rysem Santholzerova myšlení pak zůstává jeho přesvědčení o kráse čisté, neaplikované matematiky, které je představeno prostřednictvím Santholzerovy polemiky s Karlem Honzíkem na stránkách Pásma. and Vilém Santholzer was a Czech radiologist who in the second half of the 1920s published around thirty articles and several of his own photographs of radiation on the pages of avant-garde journals. The article explores his activities and situates them in the context of the interest of the European avant-garde in the machine aesthetic on the one hand and scientific photography on the other. It shows that for Santholzer beauty was always the direct result of other properties of an object associated with truth; in his view, machines were something beautiful if they were functional, and photographs were beautiful if they were authentic. While we can connect his thought on the machine aesthetic with the ideas of Russian constructivism, Le Corbusier, Karel Teige or Werner Graeff, in the case of his photographs we can find parallels among authors interested in the power of photography to make the invisible visible, i.e. above in the work of László Moholy-Nagy and once again Karel Teige. What then remains a peculiar feature of Santholzer’s thought is his belief in the beauty of pure, unapplied mathematics, which he set out in his polemics with Karel Honzík on the pages of Pásmo.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public