Optical Images of Molecular Vibronic Couplings from Tip-Enhanced Fluorescence Excitation Spectroscopy

The system-plus-bath model is an important tool to understand nonadiabatic dynamics for large molecular systems. The understanding of the collective motion of a huge number of bath modes is essential to reveal their key roles in the overall dynamics. We apply the principal component analysis (PCA) to investigate the bath motion based on the massive data generated from the MM-SQC (symmetrical quasi-classical dynamics method based on the Meyer-Miller mapping Hamiltonian) nonadiabatic dynamics of the excited-state energy transfer dynamics of Frenkel-exciton model. The PCA method clearly clarifies that two types of bath modes, which either display the strong vibronic couplings or have the frequencies close to electronic transition, are very important to the nonadiabatic dynamics. These observations are fully consistent with the physical insights. This conclusion is obtained purely based on the PCA understanding of the trajectory data, without the large involvement of pre-defined physical knowledge. The results show that the PCA approach, one of the simplest unsupervised machine learning methods, is very powerful to analyze the complicated nonadiabatic dynamics in condensed phase involving many degrees of freedom.

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Enhanced-Fluorescence of a Dye on DNA- assembled Gold Nano-Dimers Discriminated by Lifetime Correlation Spectroscopy

10.26434/chemrxiv.5728446.v1 ◽

2017 ◽

Author(s):

Pedro M. R. Paulo ◽

David Botequim ◽

Agnieszka Jóskowiak ◽

Sofia Martins ◽

Duarte M. F. Prazeres ◽

...

Keyword(s):

Single Molecule ◽

Fluorescence Emission ◽

Directed Assembly ◽

Plasmon Mode ◽

Correlation Spectroscopy ◽

Enhanced Fluorescence ◽

Detection Volume ◽

Relaxation Component ◽

Good Agreement ◽

Confocal Detection

<div> <div> <div> <p>We have employed DNA-directed assembly to prepare dimers of gold nanoparticles and used their longitudinally coupled plasmon mode to enhance the fluorescence emission of an organic red-emitting dye, Atto-655. The plasmon- enhanced fluorescence of this dye using dimers of 80 nm particles was measured at single molecule detection level. The top enhancement factors were above 1000-fold in 71% of the dimers within a total of 32 dimers measured, and, in some cases, they reached almost 4000-fold, in good agreement with model simulations. Additionally, fluorescence lifetime correlation analysis enabled the separation of enhanced from non-enhanced emission simultaneously collected in our confocal detection volume. This approach allowed us to recover a short relaxation component exclusive to enhanced emission that is attributed to the interaction of the dye with DNA in the interparticle gaps. </p> </div> </div> </div>

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On the Use of Optcial Devices by European Landscape Painters in the 18th and 19th Century and the Traits of Optical Images: In Relation to the Hockney-Falco Thesis and Debate

Journal of Contemporary Art Studies ◽

10.29330/jcas.2019.12.23.2.35 ◽

2019 ◽

Vol 23 (2) ◽

pp. 35-60

Author(s):

Sang-Myon LEE

Keyword(s):

19Th Century ◽

Optical Images

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Faculty Opinions recommendation of A reversibly photoswitchable GFP-like protein with fluorescence excitation decoupled from switching.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13373029.14743156 ◽

2011 ◽

Author(s):

Jacques Neefjes ◽

Malgorzata Garstka

Keyword(s):

Fluorescence Excitation

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Monitoring effluent quality in hypertrophic wastewater reservoirs using remote sensing

Water Science & Technology ◽

10.2166/wst.1996.0148 ◽

1996 ◽

Vol 33 (8) ◽

pp. 23-29 ◽

Cited By ~ 3

Author(s):

I. Dor ◽

N. Ben-Yosef

Keyword(s):

Water Quality ◽

Theoretical Model ◽

Principal Component ◽

Cost Effective ◽

Operational Parameters ◽

Effluent Quality ◽

Optical Images ◽

Routine Monitoring ◽

Cost Effective Method ◽

Wastewater Quality

About one hundred and fifty wastewater reservoirs store effluents for irrigation in Israel. Effluent qualities differ according to the inflowing wastewater quality, the degree of pretreatment and the operational parameters. Certain aspects of water quality like concentration of organic matter, suspended solids and chlorophyll are significantly correlated with the water column transparency and colour. Accordingly optical images of the reservoirs obtained from the SPOT satellite demonstrate pronounced differences correlated with the water quality. The analysis of satellite multispectral images is based on a theoretical model. The model calculates, using the radiation transfer equation, the volume reflectance of the water body. Satellite images of 99 reservoirs were analyzed in the chromacity space in order to classify them according to water quality. Principal Component Analysis backed by the theoretical model increases the method sensitivity. Further elaboration of this approach will lead to the establishment of a time and cost effective method for the routine monitoring of these hypertrophic wastewater reservoirs.

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