Photothermal beam deflection: a new method for in vivo measurements of thermal energy dissipation and photochemical energy conversion in intact leaves

1990 ◽  
Vol 24 (1) ◽  
pp. 63-73 ◽  
Author(s):  
Michel Havaux ◽  
Lucie Lorrain ◽  
Roger M. Leblanc
Keyword(s):  
Energy Dissipation ◽  
Energy Conversion ◽  
Thermal Energy ◽  
New Method ◽  
Beam Deflection ◽  
In Vivo Measurements ◽  
Thermal Energy Dissipation ◽  
Intact Leaves

Thermal-Energy Dissipation

1982 ◽  
Vol 70 (4) ◽  
pp. 475-480 ◽  
Author(s):  
Kenneth H. Cohn ◽  
James W. May
Keyword(s):  
Energy Dissipation ◽  
Thermal Energy ◽  
Thermal Energy Dissipation

Thermal Energy Dissipation by SiO2-Coated Plasmonic-Superparamagnetic Nanoparticles in Alternating Magnetic Fields

2013 ◽  
Vol 25 (22) ◽  
pp. 4603-4612 ◽  
Author(s):  
Georgios A. Sotiriou ◽  
Michelle A. Visbal-Onufrak ◽  
Alexandra Teleki ◽  
Eduardo J. Juan ◽  
Ann M. Hirt ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Magnetic Fields ◽  
Thermal Energy ◽  
Superparamagnetic Nanoparticles ◽  
Thermal Energy Dissipation ◽  
Alternating Magnetic Fields

Wide variation of winter-induced sustained thermal energy dissipation in conifers: a common-garden study

Oecologia ◽  
2021 ◽  
Author(s):  
A. Walter-McNeill ◽  
M. A. Garcia ◽  
B. A. Logan ◽  
D. M. Bombard ◽  
J. S. Reblin ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Thermal Energy ◽  
Common Garden ◽  
Thermal Energy Dissipation

scholarly journals Lhcx proteins provide photoprotection via thermal dissipation of absorbed light in the diatom Phaeodactylum tricornutum

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jochen M. Buck ◽  
Jonathan Sherman ◽  
Carolina Río Bártulos ◽  
Manuel Serif ◽  
Marc Halder ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Cross Section ◽  
Thermal Energy ◽  
Absorption Cross Section ◽  
Phaeodactylum Tricornutum ◽  
Thermal Dissipation ◽  
Absorption Cross ◽  
Dissipation Process ◽  
Thermal Energy Dissipation ◽  
Holistic Understanding

Abstract Diatoms possess an impressive capacity for rapidly inducible thermal dissipation of excess absorbed energy (qE), provided by the xanthophyll diatoxanthin and Lhcx proteins. By knocking out the Lhcx1 and Lhcx2 genes individually in Phaeodactylum tricornutum strain 4 and complementing the knockout lines with different Lhcx proteins, multiple mutants with varying qE capacities are obtained, ranging from zero to high values. We demonstrate that qE is entirely dependent on the concerted action of diatoxanthin and Lhcx proteins, with Lhcx1, Lhcx2 and Lhcx3 having similar functions. Moreover, we establish a clear link between Lhcx1/2/3 mediated inducible thermal energy dissipation and a reduction in the functional absorption cross-section of photosystem II. This regulation of the functional absorption cross-section can be tuned by altered Lhcx protein expression in response to environmental conditions. Our results provide a holistic understanding of the rapidly inducible thermal energy dissipation process and its mechanistic implications in diatoms.

scholarly journals Modeling irreversible molecular internal conversion using the time-dependent variational approach with sD2 ansatz

2020 ◽  
Vol 22 (16) ◽  
pp. 8952-8962
Author(s):  
Mantas Jakučionis ◽  
Tomas Mancal ◽  
Darius Abramavičius
Keyword(s):  
Energy Dissipation ◽  
Thermal Energy ◽  
Variational Approach ◽  
Internal Conversion ◽  
Time Dependent ◽  
Thermal Energy Dissipation

A model of irreversible molecular internal conversion dynamics due to molecular thermal energy dissipation to the bath is presented.

scholarly journals Physiological Characteristics of Photosynthesis in Yellow-Green, Green and Dark-Green Chinese Kale (Brassica oleracea L. var. alboglabra Musil.) under Varying Light Intensities

Plants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 960
Author(s):  
Kuan-Hung Lin ◽  
Feng-Chi Shih ◽  
Meng-Yuan Huang ◽  
Jen-Hsien Weng
Keyword(s):  
Electron Transport ◽  
Energy Dissipation ◽  
Light Intensity ◽  
Thermal Energy ◽  
Electron Transport Rate ◽  
Transport Rate ◽  
Physiological Characteristics ◽  
Chinese Kale ◽  
Thermal Energy Dissipation ◽  
Dark Green

The objective of this work was to study physiological characteristics and photosynthetic apparatus in differentially pigmented leaves of three Chinese kale cultivars. Chlorophyll (Chl) fluorescence and photochemical reflectance index (PRI) measurements in green, yellow-green, and dark-green cultivars in response to varying light intensities. As light intensity increased from 200 to 2000 photosynthetic photon flux density (PPFD), fraction of light absorbed in photosystem (PS) II and PRI values in all plants were strongly lowered, but fraction of light absorbed in PSII dissipated via thermal energy dissipation and non-photochemical quenching (NPQ) values in all plants wereremarkably elevated.When plants were exposed to 200 PPFD, the values of fraction of light absorbed in PSII, utilized in photosynthetic electron transport(p), andfraction of light absorbed excitation energy in PSII dissipated via thermal energy dissipation (D), remained stable regardless of the changes in levels of Chla + b. Under 800 and 1200 PPFD, the values of p and electron transport rate (ETR) decreased, but D and NPQ increased as Chla + bcontent decreased, suggesting that decrease inChla + bcontent led to lower PSII efficiency and it became necessary to increase dissipate excess energy. On the contrary, in 2000 PPFD, leaves with lower Chla + bcontent had relatively higher p and electron transport rate (ETR) values and lower D level, as well as tended to increase more in NPQ but decrease more in PRI values. The consistent relations between PRI and NPQ suggest that NPQ is mainly consisted ofthe xanthophyll cycle-dependentenergy quenching.Yellow-green cultivar showed lower Chla + bcontent but high carotenoids/Chla + b ratio and had high light protection ability under high PPFD. The precise management of photosynthetic parameters in response to light intensity can maximize the growth and development of Chinese kale plants.

Dynamic response of plant chlorophyll fluorescence to light, water and nutrient availability

2015 ◽  
Vol 42 (8) ◽  
pp. 746 ◽  
Author(s):  
M. Pilar Cendrero-Mateo ◽  
A. Elizabete Carmo-Silva ◽  
Albert Porcar-Castell ◽  
Erik P. Hamerlynck ◽  
Shirley A. Papuga ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Thermal Energy ◽  
Plant Stress ◽  
Nutrient Deficiency ◽  
Light Response ◽  
Response Curves ◽  
Light Response Curves ◽  
Thermal Energy Dissipation ◽  
Response To Water ◽  
The Relationship

Chlorophyll molecules absorb photosynthetic active radiation (PAR). The resulting excitation energy is dissipated by three competing pathways at the level of photosystem: (i) photochemistry (and, by extension, photosynthesis); (ii) regulated and constitutive thermal energy dissipation; and (iii) chlorophyll-a fluorescence (ChlF). Because the dynamics of photosynthesis modulate the regulated component of thermal energy dissipation (widely addressed as non-photochemical quenching (NPQ)), the relationship between photosynthesis, NPQ and ChlF changes with water, nutrient and light availability. In this study we characterised the relationship between photosynthesis, NPQ and ChlF when conducting light-response curves of photosynthesis in plants growing under different water, nutrient and ambient light conditions. Our goals were to test whether ChlF and photosynthesis correlate in response to water and nutrient deficiency, and determine the optimum PAR level at which the correlation is maximal. Concurrent gas exchange and ChlF light-response curves were measured for Camelina sativa (L.) Crantz and Triticum durum (L.) Desf plants grown under (i) intermediate light growth chamber conditions, and (ii) high light environment field conditions respectively. Plant stress was induced by withdrawing water in the chamber experiment, and applying different nitrogen levels in the field experiment. Our study demonstrated that ChlF was able to track the variations in photosynthetic capacity in both experiments, and that the light level at which plants were grown was optimum for detecting both water and nutrient deficiency with ChlF. The decrease in photosynthesis was found to modulate ChlF via different mechanisms depending on the treatment: through the action of NPQ in response to water stress, or through the action of changes in leaf chlorophyll concentration in response to nitrogen deficiency. This study provides support for the use of remotely sensed ChlF as a proxy to monitor plant stress dynamics from space.

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