Single & Two-photon Excited Fluorescence of Two New Compounds with 2-Benzothiazolyl as Electron Acceptor

Two new D--A type compounds, where electron-donor D is tertiary amino group, electron-acceptor A is 2-benzothiazolyl and ?is two conjugated styryl units, have been synthesized. They are named as trans, trans-2-{4-[4-(N, N-diethylamino)styryl]styryl}-1, 3-benzothiazole and trans, trans-2-{4-[4-(N, N-diphenylamino)styryl]styryl}-1, 3-benzothiazole. Both compounds show strong two-photon excited fluorescence in yellow-orange region when excited by a femtosecond laser at 800 nm.

In vivo auditory nerve stimulation with visible light

Background:Infrared laser stimulation has been proposed as an innovative method to elicit an auditory nerve response.Most studies have focused on usi ng long-wavelength infrared(>980 nm)pulsod lasers with high water absoption cofficients.This paper sought to assts8 whether a short-wavelength laser(465 nm)with an absorption cofficient as low as 103 cm^(-1) would activate the auditory nerve and studied its potential mechanism.Method:Optical compound action potentials(OCAPs)were recorded when synchronous triger laser pulses st imulate the cochlea before and after deafening,varying the pulse durations(from 8001us to 36001us)and the amount of radiant enengy(fom 18.05 mJ/cm^(2) to 107.91 mJ/cm^(2)).A thermal infrared imager was applied to monitor the tempenature change of the guinea pig cochlea.Results:The results showed that pulsed laser stimulation at 465 nm could invoke OCAPs and had a similar waveform compared to the acoustical compound action potentials.The amplitude of OCAPs had a poaitive correlation with the in-creasi ng laser peak power,while the latency of OCAPs showed a negative correlation.The imager data showed that the temperature in thecochlea rose quickly by about 0.3℃ right after stimulating the cochlea and decreased quickly back to the initial temperature as the stimulation ended.Con-clusions:This paper demonstrates that 465-nm laser st imulation can successfully induce OCAPs outside the cochlea,and that the amplitude and latency of the invoked OCAPs are highly affected by laser peak power.This paper proposes that a photothermal efect might be the main mechanism for the auditory nerve response induced by short-wavelength laser stimulation.

Photoacoustic effect invokes auditory response in infrared neuron stimulation

Infrared neuron stimulation is regarded as an innovative approach for stimulating cochleae in animals while the exact mechanism still remains unknown.In this paper,we studied compound action potentials of guinea pig cochleae with chronic or acute deafness.We recorded optical compound action potentials and analyzed stretched cochlear preparations by fiuorescence microscopy.Photoacoustic signals were measured by hydrophone and microphone,respectively.In our experiment,we observed a switch response effect in vitro and in vivo experiments.Therefore,we proposed photoacoustic effect could invoke auditory response in infrared neuron stimulation.

Hydrothermal synthesis and optical properties of Zn_(1-x)Mn_xS nanorods

Zn1-xMnxS （x = 0-0.05） nanorods were successfully synthesized through a hydrothermal route. The morphology, composition and microstructure of Zn1-xMnxS nanorods were characterized respectively by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Raman spectrometer. The optical properties of Zn1-xMnxS nanorods were determineded by UV-Vis absorption spectroscopy and photo- luminescence （PL） emission spectroscopy. The results show that the introduction of Mn^2＋ on interstitial sites in ZnS lattice has significant influence on the Raman spectra, UV-Vis absorption spectra and PL emis- sion spectra. With the increase of Mn^2＋, the lengths of the sampled nanorods become shorter and the morphologies of the products show disorder accompanied by some nanoparticles. The absorption band edge shifts to longer wavelength. The intensity of the ZnS-related emission gradually becomes weaker, whereas, the Mn^2＋-related broad emission spectra located at 580 nm gradually red-shifts and increases. Occupation of Zn^2＋ sites in the lattice by Mn^2＋ ions results in lattice distortion and influences the energy level structure of ZnS. The Mn doping is found responsible for the changes in the defect-related emission of the ZnS nanorods.