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About Omics Group OMICS GroupOMICS Group International through its Open Access Initiative is committed to make genuine and reliable contributions to the.

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Presentation on theme: "About Omics Group OMICS GroupOMICS Group International through its Open Access Initiative is committed to make genuine and reliable contributions to the."— Presentation transcript:

1 About Omics Group OMICS GroupOMICS Group International through its Open Access Initiative is committed to make genuine and reliable contributions to the scientific community. OMICS Group hosts over 400 leading- edge peer reviewed Open Access Journals and organize over 300 International Conferences annually all over the world. OMICS Publishing Group journals have over 3 million readers and the fame and success of the same can be attributed to the strong editorial board which contains over eminent personalities that ensure a rapid, quality and quick review process. OMICS Group

2 About Omics Group conferences OMICS Group signed an agreement with more than 1000 International Societies to make healthcare information Open Access. OMICS Group Conferences make the perfect platform for global networking as it brings together renowned speakers and scientists across the globe to a most exciting and memorable scientific event filled with much enlightening interactive sessions, world class exhibitions and poster presentationsOMICS GroupOMICS Group Omics group has organised 500 conferences, workshops and national symposium across the major cities including SanFrancisco,Omaha,Orlado,Rayleigh,SantaClara,C hicago,Philadelphia,Unitedkingdom,Baltimore,SanAnt anio,Dubai,Hyderabad,Bangaluru and Mumbai.

3 Leonas Valkunas Institute of Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania Chair of Theoretical Physics Faculty of Physics, Vilnius University, Lithuania Current research interests: Excitation and charge transfer in photosynthesis, Spectroscopy of molecular structures and biological macromolecules, Nonlinear optics and spectroscopy, Disordered solid states Exciton theory

4 Leonas Valkunas Publications 1. N. Holt, D. Zigmantas, L. Valkunas, X.-P. Li, K. Niyogi and G. R. Fleming. Carotenoid cation formation and the regulation of photosynthetic light harvesting. Science 307, , Y.-Z. Ma, L. Valkunas, S. L. Dexheimer, S. M. Bachilo, G. R. Fleming. Femtosecond spectroscopy of optical excitations in single-walled carbon nanotubes: evidence for exciton-exciton annihilation. Phys. Rev. Lett. 94, , C. D. P. Duffy, L. Valkunas, A. P. Ruban. Light-harvesting processes in the dynamic photosynthetic antenna. Perspective. Phys. Chem. Chem. Phys. 15, 18752, F. D. Fuller, J. Pan, A. Gelzinis, V. Butkus, S. S. Senlik, D. E. Wilcox, C. F. Yokum, L. Valkunas, D. Abramavicius, J. P. Ogilvie. Vibronic coherence in oxigenic photosynthesis. Nature Chemistry. Online 13 July, 2014 (doi: /nchem.2005). 5.E. Belgio, E. Kapitonova, J. Chmeliov, C. D. P. Duffy, P. Ungerer, L. Valkunas, A. V. Ruban. Economic photoprotection in photosystem II that retains a complete light-harvesting system with slow energy traps. Nature Communications. Online 11 July, 2014 (doi: 10:1038/ncomms.5433). Books 1.H. van Amerongen, L.Valkunas, R. van Grondelle. Photosynthetic excitons. World Scientific. Singapore, New Jersey, London, Hong Kong, 590 p L. Valkunas, D. Abramavicius, T. Mancal. Molecular excitation dynamics and relaxation. Quatum theory and spectroscopy. Wiley-VCH, Weinheim, p. 445, 2013.

5 Excitation Migration, Quenching and Regulation of Photosynthetic Light Harvesting Leonas Valkunas Institute of Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania Chair of Theoretical Physics Faculty of Physics, Vilnius University, Lithuania

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7 Single molecule spectroscopy of the LHCII trimer

8 Fluorescence traces

9 Model: potential surfaces of states Describes fast intramolecular vibrations Describes slow structural changes of protein

10 Modeling results

11 Fluorescence from variously-sized PSIIs Caffarri et al. Biophys. J. 2011;100: % α-DM

12 Chl bulk k1k1 k2k2 k3k3 γ an k4k4 * * Chl - + Zea + Chl-Zea 664 nm λ detect = 1000 nm λ detect = 540 nm Chl-Zea λ detect = 680 nm Data Analysis Scheme Holt, N. E.; Zigmantas, D. Et al. Science 2005, 307,

13 Fluctuating antenna model Ideal 2D square lattice: The lack of connectivity at some antenna points may be accounted by fractional dimension d: Diffusion limit

14 L. Valkunas, D. Abramavicius, and T. Mancal Molecular Excitation Dynamics and Relaxation Quantum Theory and Spectroscopy

15 2D photon echo spectroscopy Scheme

16 Purely electronic/vibrational systems Electronic dimer Vibrational monomer Electronic dimer Vibrational monomer V. Butkus et al. CPL 545 (2012)

17 Effects of the inhomogeneous disorder on coherences The amplitude of the electronic-character beats is dramatically reduced by the disorder Vibrational-character beats weakly depend on the disorder ω 0 =600 cm -1 ΔE=850 cm -1 s 1 =s 2 =0.05 σ D =0 σ D =200 cm -1 σ D =20 cm -1 σ D =50 cm -1

18 2D spectrum of the PSII RC at 77K at a waiting time of 170 fs. F. D. Fuller et al. Vibronic coherence in oxygenic photosynthesis. Nature Chemistry DOI: /nchem.2005 (2014)

19 Exciton Dynamics in Semiconducting Carbon Nanotubes Leonas Valkunas Center for Physical Sciences and Technology, Vilnius and Department of Theoretical Physics at Vilnius University, Lithuania

20 Comparison of the E 1 and E 2 kinetics and their intensity dependence Y.-Z. Ma et al., Phys. Rev. Lett. 94 (2005)

21 Theoretical description of exciton-exciton annihilation When (1) k 21 and k n2 >> 1/  p, and (2) (i = 1,2 and n)

22 Let Us Meet Again We welcome all to our future group conferences of Omics group international Please visit:


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