The effect of pH on the fluorescence efficiency of fluorescein is evaluated using thermal lens technique. Fluorescence efficiency increases as the sample becomes more and more alkaline. But when fluorescein is mixed with rhodamine B fluorescence quenching of fluorescein takes place with the excitation of rhodamine B. The electronic energy transfer in this mixture is investigated using Optical P...

We developed a new surface-selective time-resolved nonlinear spectroscopy, femtosecond time-resolved electronic sum-frequency generation (TR-ESFG) spectroscopy, to investigate ultrafast dynamics of molecules at liquid interfaces. Its advantage over conventional time-resolved second harmonic generation spectroscopy is that it can provide spectral information, which is realized by the multiplex d...

Mesoporous amorphous and nanocrystalline titanium dioxide were prepared by simple and environmental friendly modified Sol-Gel method using cationic (C14TAB, C16TAB, C18TAB) and nonionic (Plantacare UP K55) surfactant as pore forming agent. The obtained particles were characterized by BET, TEM, FT-IR and XRD techniques. The effect of cationic surfactant chain...

I use a set of machines based on the concept of nested rule systems built on the a modified version of the Wolfram elemental cellular automata to investigate the role of recombination in providing resistance to ageing. Class III and class IV machines are observed to respond differently to recombination. Class IV machines show recombinational centring in their neutral networks whereas class III ...

We investigate the construction of all the periodic structures or “ gliders ” up to now known in the evolution space of the onedimensional cellular automaton Rule 110. The production of these periodic structures is developed and presented by means of glider collisions. We provide a methodology based on the phases of each glider to establish the necessary conditions for controlling and displayin...

The pathway of rhodamine 123 was examined after injection into Sarcophaga flies and after in vitro labeling of the Malpighian tubules. After in vitro labeling the primary cells only retained this potential-sensitive dye for a short period while all secondary cells accumulated the dye from the tubule lumen. In vivo the secondary cells also accumulated rhodamine 123 from the lumen, but the primar...

Fluorescent molecules are indispensable tools in modern biochemical and biological research, being used as labels for biomolecules, indicators for ions, stains for organelles, and substrates for enzymes. The major targets of this last class are hydrolases that catalyze the removal of a masking moiety, thereby modulating fluorescence. A critical property of fluorogenic hydrolase substrates is th...

Previous studies by our laboratory have suggested the potential role of receptor-mediated endocytosis components in the cellular translocation of riboflavin (vitamin B2). To delineate the intracellular compartments and events involved in the internalization of riboflavin, we synthesized a rhodamine-labeled riboflavin conjugate to monitor its movement via fluorescent microscopy. Cellular uptake ...

Rhodamine B, a dye commonly used in a variety of biological studies was incorporated into the bodies of male tobacco budworm moths, Heliothis virescens (Lepidoptera: Noctuidae), by allowing them to feed freely on 0.1% rhodamine dissolved in a 10% sucrose solution. After exposing males for one to three days to this pigment, rhodamine was clearly detectable in >82% of spermatophores extracted fro...

A colorless and non-fluorescent rhodamine derivative, rhodamine B hydrazide (RH), is applied to detect nitric oxide and form fluorescent rhodamine B (RB). The reaction mechanism of RH with NO is proposed in this study. The probe shows good stability over a broad pH range (pH>4). Furthermore, fluorescence intensity of RH displays an excellent linearity to the NO concentration and the detection l...