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教育実践報告, This article is a teaching experiment report. First of all, I reflect on the existing problems in the teaching of Chinese composition in Osaka University. In response to these problems, I have designed a new mode of teaching compositions. Different from the previous "essay-commentary" mode, which emphasizes "learning from mistakes", the new model emphasizes successful learning experience. Through group discussion, the new mode provides opportunities for students to find the success of writing among themselves and peers. In the new model, the teacher also changed from a simple writing teacher to an author, writing together with the students. Through group discussion, students come to realize the language skills and writing skills that can be learned from the teacher's essay. Hence, the new mode was called “essay-discovery” mode of teaching compositions.

Black silicon, which is obtained by irradiating the surface of a Si wafer with femtosecond laser pulses in the presence of a sulfur-bearing gas, holds great promise in the preparation of high-performance intermediate band silicon solar cells. Using a three-level model, the enhanced usefulness of sunlight of the microstructured silicon was firstly analyzed. A detailed study on the relationship between the light loss, the ionization energy of doped impurities in silicon and the impurity band width were given. Then the effect of the position of intermediate band within the forbidden gap of silicon on the theoretical conversion efficiency for the corresponding solar cell is discussed using the Detailed Balance Theory. Finally problems need to be resolved in making intermediate band solar cells based on femtosecond laser microstructured silicon are pointed out with great emphasis.

According to the principle of light propagation,an automatic measurement system for scattering light survey of meridian and surrounding non-meridian at 808 nm central wavelength was designed and the effect of laser power on light decay rate of tissue were discussed.The diffusion theory of light transporting in biological tissues was used to analyze the experimental results.The results showed that there were statistical differences between meridian and surrounding non-meridian(P0.05).We also found the differences in optical parameters that the average attenuation factor value of pericardium meridian was lower than spleen meridian.In this article,our study showed laser power had no influence on attenuation of light in biological tissues that proved the attenuation is determined by tissue optical characteristics.

This paper critically analyses and simulates the circuit configuration of the integral gated mode single photon detector which is proposed for eliminating the transient spikes problem of conventional gated mode single photon detector. The relationship between the values of the circuit elements and the effect of transient spikes cancellation has been obtained. With particular emphasis, the bias voltage of the avalanche photodiode and the output signal voltage of the integrator have been calculated. The obtained analysis results indicate that the output signal voltage of the integrator only relates to the total quantity of electricity of the avalanche charges by choosing the correct values of the circuit elements and integral time interval. These results can be used to optimize the performance of single photon detectors and provide guides for the design of single photon detectors.

An intrinsically stable quantum key distribution system (QKD) with six polarization states encoded by phase modulation is introduced. The encoder and decoder are in the same structures that consist of two polarizing Sagnac interferometers connected in tandem. The six polarization states are determined and distinguished by different sets of phase shifts induced by two respective electrically-driven integrated phase modulators. A mean visibility of interference fringes is kept stable at 97.58% for an hour's performance. Theoretical and experimental analyses show that the proposed QKD system features intrinsically stability immune from environment fluctuation.

By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows that the self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation.

Employing the technique of symmetry reduction of analytic method, we solve the Ginzburg–Landau equation with varying nonlinear, dispersion, gain coefficients, and gain dispersion which originates from the limiting effect of transition bandwidth in the realistic doped fibres. The parabolic asymptotic self-similar analytical solutions in gain medium of the normal GVD is found for the first time to our best knowledge. The evolution of pulse amplitude, strict linear phase chirp and effective temporal width are given with self-similarity results in longitudinal nonlinearity distribution and longitudinal gain fibre. These analytical solutions are in good agreement with the numerical simulations. Furthermore, we theoretically prove that pulse evolution has the characteristics of parabolic asymptotic self-similarity in doped ions dipole gain fibres.

Because the rates of quantum key distribution systems are too low, the interleaving technique and interpolation technique are used to extend the capacity of the quantum key warehouse to increase the quantum key rates of quantum secure communication systems. The simulation shows that the interleaving technique and interpolation technique can extend random sequences and that their randomness are invariable. The correlative theory and technique of digital signal processing is an effective method of extending the quantum key warehouse.

The evolution of soliton trains in dispersion-shifted fibres (DSFs) in the presence of third-order dispersion (TOD) is investigated. The results show that the collision of neighbouring solitons in the trains can be suppressed by means of a proper TOD, but the maximum transmission distance (or bandwidth) is limited by the increasing soliton separation that results from the TOD. It is also shown that the separation can be suppressed by adjusting the initial phase or amplitude difference between the solitons. These results are helpful to re-establish the potential application of the soliton-based optical-communication systems in DSFs.

A new approach is proposed to enhance supercontinuum (SC) spectrum generation in A dispersion-decreasing optical fibre with a new dispersion profile. The chromatic dispersion D(?,z) is a concave function of wavelengths and has no zero-dispersion wavelengths over the whole or part of the fibre as D(?,z) is positive. A flatter and much broader spectrum can be produced based on the scheme. The general criteria parameters are obtained for characterizing SC shapes in the optical fibres.

The nonlinear effect of two-photon excitation on the imaging property of two-photon confocal microscopy has been analyzed by the two-photon fluorescence intensity transfer function derived in this paper. The two-photon fluorescence intensity transfer function in a confocal microscopy is given. Furthermore the three-dimensional point spread function (3D-PSF) and the three-dimensional optical transfer function (3D-OTF) of two-photon confocal microscopy are derived based on the nonlinear effect of two-photon excitation. The imaging property of two-photon confocal microscopy is discussed in detail based on 3D-OTF. Finally the spatial resolution limit of two-photon confocal microscopy is discussed according to the uncertainty principle.

In this paper, we report on the enhanced pulse compression due to the interaction between the positive third-order dispersion (TOD) and the nonlinear effect (cross-phase modulation effect) in birefringent fibres. Polarization soliton compression along the slow axis can be enhanced in a birefringent fibre with positive third-order dispersion, while the polarization soliton compression along the fast axis can be enhanced in the fibre with negative third-order dispersion. Moreover, there is an optimal third-order dispersion parameter for obtaining the optimal pulse compression. Redshifted initial chirp is helpful to the pulse compression, while blueshifted chirp is detrimental to the pulse compression. There is also an optimal chirp parameter to reach maximum pulse compression. The optimal pulse compression for TOD parameters under different N-order solitons is also found.

In this paper, we investigate the modulation instability for generating femtosecond pulses in fibres with slowly decreasing dispersion. Higher-order dispersion and higher-order nonlinear effects are taken into account when the continuous wave or quasi-continuous wave evolves into sub-picosecond and femtosecond pulses by modulation instability in the optical fibres. Our research results show that the gain spectrum of the dispersion-decreasing fibres is much wider than that in conventional fibres. The third-order dispersion effect has no contribution to gain spectrum, while the self-steepening effect reduces the maximum value and gain bandwidth and the Raman self-scattering effect widens the extent to which the modulation instability occurs.

Protein phosphatase 1, regulatory subunit 13 like PPP1R13L, also coined iASPP, was found high expression in prostate cancer tissues and cell lines. In previous research, in vitro and in vivo RNAi mediated by artificial lentiviral shRNAs which proved that suppression of iASPP decrease the proliferation of cancer cells. Endogenous interference RNAs, microRNAs play key roles in cell proliferation by post-transcriptional regulation of gene expression. Natural base pair matched microRNA for iASPP is mir124, which was found high expression in growth factorloss prostate cancer cell lines. In this study we examined effect of mir124 upon iASPP and proliferation of prostate cells in vitro with lentiviral infection and use artificial shRNA as control. In vitro reporter assay confirmed that mir124 binding the 3'UTR of iASPP and suppress mRNA expression. Lentivirus mediated mir124 expression decreased the proliferation and viability of PC3 while endogenous iASPP were knocked down.

A simple and novel strain method is used to change a uniform grating into a linearly chirped grating. Independent tuning of the chirp and the center wavelength of the fiber grating is demonstrated. A 10?Gb?s-1 transmission over 100 km of standard single-mode fiber is realized using this strain method. It is deduced that the product of the maximum dispersion compensation bandwidth and the corresponding dispersion is nearly equal to a constant by numerical simulation.

The nonlinear Schr?dinger equation (NLSE) in erbium-doped fiber (EDF) was obtained. The cross-phase modulation (XPM) in the erbium-doped fiber amplifiers (EDFA) was studied based on this NLSE and the rate equations. A more generalized form of the propagation equation in EDFA was obtained which included the phase shifts the EDFA induced. An analytical expression was given to the XPM in the EDFA. It was found that the XPM in the EDFA dose not change very much with the wavelength except at the neighboring wavelengths (around 1531 nm) where the absorption and emission cross-sections of the erbium ions reach their maxima, and the XPMs have opposite signs on the two sides around 1531 nm. Furthermore, it was found that the XPM increases with the increase of the length of EDF.

First- and second-order Raman spectra of carbon nanotubes produced in helium and argon atmospheres at a pressure ranging from 11 to 92 kPa by arc discharge have been measured and compared with each other. The position and bandwidth of the spectral lines depend on the kind of inert gases and their pressure. The Raman spectra of the nanotubes produced in argon gas atmosphere are much more similar to that of polycrystalline graphite than those of the nanotubes produced in helium gas atmosphere. The position and bandwidth of nanotube Raman peaks change with gas pressure in arc discharge because different diameter distribution of nanotubes is produced at different inert gas pressure. The Raman spectra of nanotubes produced at high pressure is much more like that of graphite than those produced in lower pressure.

We first present the general solution and the simplest special solution of the doubly stochastic matrix used in deterministic entanglement concentration. Then, we give a better scheme to realize deterministic entanglement concentration. Under this scheme, the concentration is realized, and more importantly, two partially entangled pairs concentrate to four-particle Greenberger–Horne–Zeilinger (GHZ) states with a certain probability.

Protein phosphatase1, regulatory subunit 13 like PPP1R13L, also coined iASPP, was found high expression in prostate cancer tissues and cell lines. In previous research, in vitro and in vivo RNAi mediated by artificial lentiviral shRNAs which proved that suppression of iASPP decrease the proliferation of cancer cells. Endogenous interference RNAs, microRNAs play key roles in cell proliferation by post-transcriptional regulation of gene expression. Natural base pair matched microRNA for iASPP is mir124, which was found high expression in growth factor-loss prostate cancer cell lines. In this study we examined effect of mir124 upon iASPP and proliferation of prostate cells in vitro with lentiviral infection and use artificial shRNA as control. In vitro reporter assay confirmed that mir124 binding the 3’UTR of iASPP and suppress mRNA expression. Lentivirus mediated mir124 expression decreased the proliferation and viability of PC3 while endogenous iASPP were knocked down.

A new region where modulation stability occurs in the fibers with minimum group-velocity was found due to the fourth-order dispersion effect. The spectral extent of the region is analyzed and found to be affected by initial input power and the dispersion parameter.

The compression results of picosecond and femtosecond soliton pulses in the dispersion-decreasing fibers are reported in this paper. We found that the high-order dispersion has a great influence on the soliton compression. The expressions of optimum compression factor and optimum fiber length are obtained numerically.

We present a tumour cell growth process model including a multiplicative coloured noise and an additive coloured noise correlated. How the noise cross-correlation intensity λ and correlation time τ can affect the steady state properties of tumour cell growth model are discussed by solving an approximative Fokker–Planck equation. It is found that the increase of noise correlation time τ can cause the tumour cell number increasing, but the increase of multiplicative noise intensity can cause the tumour cell number extinction. We also find that the increase of cross-correlation intensity λ in the case of 0

Alzheimer’s disease irreversibly and progressively damages the brain, but the treatments in clinical trials are too slow. So, we hypothesized that the presence of erythrocyte variants with AD could be used as a noninvasive means to predict or trigger for administration of the preventive therapeutics, and the aim of this study is to develop a method using Raman spectroscopy in a rat model of Aβ 25−35 -induced neurotoxicity, and then evaluate the protective effect of bajijiasu by this method. Results showed that the Raman spectra fingerprints of the erythrocyte of model group were obvious different from those of the normal control, as peaks around the region 650 cm −1 belonged to the s–s makers, 1605 cm −1 corresponded to the high spin (deoxygenated-Hb) marker, 1374 cm −1 arises from ν4 as a sign of concentration of O 2 , and 1123 and 1033 cm −1 are associated with the trans stretching vibrations of CAC skeleton. Results also showed that bajijiasu can make these changes recover. Our study also suggested that erythrocyte variants detected using Raman spectroscopy should be tested in a specific longitudinal study for the association with AD diagnosis, and if positive, can be used as a prognostic marker.

A new method is proposed to compress soliton pulses in the normal dispersive optical fibers through cross-phase-modulation of two pulses. The optimum fiber length for optimum compression is obtained for given values of the pulses and fiber parameters.

We investigate the adiabatic enhanced compression of ultrashort pulses from a distributed feedback laser operated at 1550 nm in fibres with slowly decreasing dispersion (FSDD). High-quality pulse compressions from 4.4 ps down to 1.1 ps in a 100 m FSDD and from 4.4 ps down to 830 fs in a 500 m FSDD are obtained. The Raman self-frequency shift of femtosecond pulses in the compression is observed. Theoretical analyses are in good agreement with experimental results.

We report on the enhanced pulse compression due to the interaction of positive third-order dispersion and cross-phase-modulation effects in birefringent fibres. Polarization soliton compression along the slow axis can be enhanced in birefringent fibres with positive third-order dispersion, and the polarization soliton compression along the fast axis can be enhanced in fibres with negative third-order dispersion. Moreover, the third-order dispersion parameter can be optimized to obtain the optimal pulse compression.

The influence of the third-order dispersion (TOD) on the polarization mode dispersion (PMD) is investigated. It is found that the TOD effect destroys orthogonal polarization modes in optical birefringent fibres. A new method is proposed to compensate for the PMD by means of cascading the fibres with the positive and negative TOD. This has proven to be practicable in long transmissions.

Starting from our definition of apodization profile functions, we discover the optimal profiles and the characteristics of defined apodization functions in sidelobe suppression. It is shown by numerical analysis that the optimal grating length is 45?mm to compensate for dispersion induced by 100?km fibres and the smoothness of the ripples in time-delay characteristics is related to the defined parameters.