Raman spectroscopy has strong potential for providing non-invasion diagnosis of cancers. In this paper, micro-Raman spectroscopy is used to diagnose one most common liver cancer, hepatocellular carcinoma (HCC). The statistical analyzes, including t-test, principal component analysis (PCA), and linear discriminant analysis (LDA), are performed on the Raman spectra of malignant and normal hepatocytes. The t-test-LDA results show that the 786- and 1004-cm^{-1} bands of the malignant and normal hepatocytes are significantly different, and PCA-LDA results show an overall accuracy of 100% for the Raman spectroscopic identification of normal and malignant hepatocytes in our experiment.

Dependence of surface-enhanced Raman scattering (SERS) from Calf thymus DNA on anions is investigated. With the silver colloid, the bands at 732, 960 and 1333 cm-1 for adenine (A), 1466 cm-1 for deoxyribose, and 1652 cm-1 for the C=O group of thymine (T) are observably enhanced. With the presence of the Cl- or SO^(2-)_(4) anions, the bands at 732 and 1326/1329 cm-1 for the symmetric stretching and skeletal vibrational modes of adenine (A) are dramatically enhanced, and the enhancement effect with the SO^(2-)_(4) ion is more than that with the Cl_ ion. The experimental results show that the DNA molecule can be adsorbed on the silver colloid particles through the C6N and N7 of adenine (A), the C=O of thymine (T) and deoxyribose. Moreover, the formed hydrogen bonding of the Cl_ or SO^(2-)_(4) ions to the C6NH2 group of adenine (A) can induce larger C6N electronegativity, which is favor for the C6N/N7 cooperative adsorption on the (Ag)^(+)_(n) colloid particles.

A self-organized thin film of a cyanine dye is fabricated by the spin-coating technique and is characterized by ultraviolet-visible spectroscopy, infrared (IR) spectroscopy, small-angle X-ray diffraction, ellipsometer, and atomic force microscopy (AFM). The nonlinear optical properties of the thin films are investigated by degenerate four wave mixing (DFWM) technique. The cyanine dye thin film sample exhibits high optical nonlinearities ('chi(3)=2.55*10^(-12) esu), and the mechanism is analyzed by the exciton coupling theory.

The dynamics of the femtosecond pulse propagation in a plasma channel is investigated by the pump-probe longitudinal diffractometry and second harmonic generation frequency-resolved optical gating (SHG-FROG) technique. The spatial characteristics, corresponding to the electronic density and the size of the channel, can be observed by the recorded ring pattern, and the spectral and temporal characteristics are recorded by the SHG-FROG traces. The spatiotemporal characteristics will help us to better understand the dynamics of the plasma induced by the femtosecond pulse and the femtosecond pulse propagating in the plasma channel.

The nonlinear optical properties of a new organic material, N-vinylcarbazole tricarbonyl chromium, are reported. The large two-photon absorption (TPA) coefficient and nonlinear refraction index are measured by an open-aperture Z-scan technique and closed-aperture Z-scan technique, respectively. The sample solution shows excellent optical limiting response.

High-order harmonic generation from one-dimensional (1D) multi-atom molecular ions in an ultra-short laser field is theoretically investigated. The dynamics of the electron in a linearly polarized intense laser field is analyzed in terms of 1D Schrodinger equation with the Crank-Nicolson algorithm. The dependence of high-order harmonics on the laser frequency and the inter-nuclear distance is discussed. It is found that the optimum range of inter-nuclear distance should be changed to get extended harmonic generation for different laser frequency, and the lower frequency laser pulse is favorable to higher order harmonic generation as the inter-nuclear distance increases.

Mitoxantrone, a clinically useful antitumour antibiotic for leukaemia and breast cancer, has received more attentions. In this paper, the interaction between mitoxantrone and calf thymus DNA is investigated by Raman and fluorescence spectroscopies, and the binding site of mitoxantrone to calf thymus DNA is explored. The results showed that mitoxantrone interacts with calf thymus DNA bases by the intercalation of anthracycline into the base pair plane of adenine (A) and thymine (T), and it results in the disruption of the hydrogen bonds between calf thymus DNA bases, and thus the calf thymus DNA double-strand can be disrupted into the B-form DNA double-strand segments.

Micro-Raman spectroscopy is employed to identify the normal and malignant human stomach cells. For the cancer cell, the reduced intensity of the Raman peak at 1250 cm^(-1) indicates that the protein secondary structure transforms from β-sheet or disordered structures to α-helical, while the increased intensity of the symmetric PO2 stretching vibration mode at 1094 cm^(-1) shows the increased DNA content. The ratio of the intensity at 1315 cm^(-1) to that at 1340 cm^(-1) reduces from 1.8 for the normal cell to 1.1 for the cancer cell in the course of canceration, and the ratio of the intensity at 1655 cm^(-1) to that at 1450 cm^(-1) increases from 1.00 for the cancer cell to 1.26 for the normal cell which indicates that the canceration of stomach cell may induce saturation of the lipid chain.

We have performed time-resolved degenerate four-wave mixing (DFWM) experiments in 75Nb_{2}O_{5 }-20TeO_{2}-5ZnO glasses dopedby Er_{2}O_{3} at different excitation intensities and lattice temperatures. DFWM signal exhibits three peaks at high excitation intensities, where a main peak appears at zero time delay and two rather weak side peaks locate symmetrically at the negative and positive time delay, respectively. The main peak is attributed to local-field effect and two side peaks areattributed to Coulomb interaction (CI).

We investigated nonlinear optical properties of ZnO-Nb_(2)O_(5)-TeO_(2) glass excited by a femtosecond laser with time-resolved four-wave mixing (FWM) technique. The unusual FWM signals were observed in samples with ZnO dopant. The mechanism for the optical nonlinearities was discussed.