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A model of two-dimensional photonic band gap structures resonant cavity is proposed made by GaAs pillars in air with graphite lattice.Its TMy mode formant wavelength changing with stress and temperature is calculated by finite difference time domain method.The results show that no mater what direction for the stress acting on the resonant cavity,there will be a good linear characteristic between the formant wavelength and the stress,the sensitivity responding to stress is 0.013 69 nm/Mpa.Meanwhile,it is found that the sensitivities responding to stress along x and y direction are the same.There is a sectional linear characteristic between the main formant wavelength and temperature for this kind of photonic crystal resonant cavity,and the biggest sensitivity responding to temperature is 1.4 nm/℃.Furthermore,the results show that there is a make-and break key characteristic for the proposed resonant cavity.

A compact,low cost,stable noncollinear optical parametric chirped pulse amplification system is studied,which is seeded by an Yb3+-doped self-starting passive mode-locked stacking pulse fiber laser centered at 1 053 nm.A gain higher than 1.1×107,single pulse energy exceeding 11 mJ with fluctuations less than 2% rms,8 nm amplified signal spectrum are achieved.Different pulse durations of amplified signal are obtained by adjusting the stacker of the Yb3+-doped self-starting passive mode-locked stacking pulse fiber laser.

A double-pass noncollinear optical parametric chirped pulse amplifier has been demonstrated. The signal is double-pass amplified in a single nonlinear crystal by a nanosecond pump pulse. The first-pass optical parametric amplification is completely phase matched in the plane of the maximum effective nonlinearity, and the other pass works symmetrically near to the first-pass optical parametric amplification plane. This architecture efficiently increases the overall gain, overcomes the optical parametric fluorescence. This scheme has been used respectively in the optical parametric chirped pulse amplifiers which the signal is an Yb-doped passively mode-locked fiber laser or a Kerr lens mode-locked Ti:sapphire oscillator.

Taking the shortest distance as the performance index and the 6-DOF fruit picking robot as the research object, the various points of path that robot passed are planned with the genetic algorithm, considering the joint velocity, acceleration and acceleration restriction. The results which are simulated with robotics toolbox of matlab indicate that the method of robot path planning not only ensures the path is optimal, but also makes the path of robot smooth.

The switching power amplifier which is the plant of magnetic suspension control system is decisive of the stability of magnetic suspension control system, so the switching power amplifier was designed for magnetic suspension. At first, the simulation model of the switching power amplifier was proposed based on MATLAB/Simulink using power system block (PSB). The validity of the modeling method was verified by the consistency of the final simulation results with the experimental results. The half bridge structure was used in the main circuit. The PWM pulse that has a changeable duty and fixed frequency was generated by the internal counter of data acquisition card (NI-PCI6221). The output horsepower was changed by regulating the duty ratio of the pulse. Finally, the intention of adjusting current was obtained.

The fluctuations of market price bring risks to supply chain enterprises, which sign some optional forward contracts in order to reduce these risks. As an effective instrument for risk management, optional forward contract has the character of flexibility and variety. This paper aims to formulate the price of the contract using the option pricing theory and obtain an optimal proportion of forward contracts and the influence factors through the risk evasion model and on the basis of the utility maximization principle.

There are lots of categorical valued and mixed numeric and categorical valued data in the practical application, and the traditional clustering methods can't analyses this kind of data very well. Aiming at the clustering of the mixed valued data, and a advanced kernel k-aggregate clustering algorithm is presented by combining the clustering analysis with kernel-based method. In this algorithm, the aggregate function (i.e. maximum entropy function) to approximate the maximum function and the categorical valued attributes decompose (CVAD) are applied in order to effectively define the computing scheme and the distance for categorical valued data. Like the fuzzy k-prototypes algorithm, the algorithm is also soft clustering, but it is more easier and insensitive to the selection of the aggregate parameter than the fuzzy one. So the algorithm is applied to the customer segmentation and gets a good clustering result which provides the managers guidance and evidence of different marketing strategies for corresponding subdivided markets. And in the clustering process the best clustering number is chosen by the significance test on five selected attributes.

Objective Diabetic macrovascular complications are the leading cause of mortality in diabetic patients. To prevent the development of this disease and to improve advanced arteriosclerosis, effective therapies directed towards the key molecular target are required. Grape seed proanthocyanidin extracts (GSPE) have been reported to be effective in treating arteriosclerosis, while little is known about the functional protein changes. Methods We used streptozotocin to induce diabetic rats. GSPE (250 mg/kg body weight/day) were administrated to diabetic rats for 24 weeks. Serum glycated haemoglobin and advanced glycation end products (AGEs) were determined. Electronic microscope was used to observe the changes of aortic ultrastructure. Immunohistochemistry was used to evaluate the receptor of advanced glycation end products (RAGE) protein expression in aortic tissue. Consequently, 2-D difference gel electrophoresis and AutoFlex martix-assisted laser desorption/ionization time-of-flight mass spectrometry with LIFT technology or liquid chromatography electrospray ionisation mass spectrometry/mass spectrometry were used to investigate aortic protein profiles among the control, untreated, and GSPE treated diabetic rats. Results GSPE significantly decreased aortic PWV, blood pressures, aortic medial thickness (p Conclusion GSPE plays an important role against diabetic macrovascular complications. Our findings might help to better understanding of the mechanism of diabetic macrovascular complications, and provide novel targets for estimating the effects of GSPE therapy.

Two resonant radio frequency fields are added to lambda three-level system in this paper. By discussing the behaviors of probing field absorption profiles under the effect of different Rabi frequencies of two radio frequency fields, the splitting of electromagnetically induced transparency (EIT) can be seen and the overlapping between EIT and gain can be obtained. The results show that the two radio frequency fields have different control functions on the system. The radio frequency field which interacts with hyperfine levels of ground state plays a role in the splitting of EIT, but the radio frequency field which interacts with hyperfine levels of excited state does not work on it. In addition only when the Rabi frequency of radio frequency field interacting with hyperfine levels of ground state is greater than with hyperfine levels of excited state, can the new features about the overlapping between EIT and gain be obtained.

The optical and electronic properties of two-dimensional atomic crystals including graphene are closely dependent on their layer numbers (or thickness). It is a fundamental issue to fast and accurately identify the layer number of multilayer flakes of two-dimensional atomic crystals before further research and application in optoelectronics. In this paper, we discuss in detail the application of transfer matrix method to simulate the optical contrast of ultrathin flakes of two-dimensional atomic crystals and further to identify their thickness, where numerical aperture of microscope objective is considered. The importance of numerical aperture in the thickness determination is confirmed by the experiments on the graphene flakes. Furthermore, two lasers with different wavelengths can be serviced as light sources for the thickness identification of flakes of two-dimensional atomic crystals with a size close to the diffraction limit of the microscope objective. The transfer matrix method is found to be very useful for the optical-contrast calculation and thickness determination of flakes of two-dimensional atomic crystals on multilayer dielectric substrate.

Objective The lower incidence of atherosclerosis in premenopausal women than in men was an established epidemiological observation. However, the incidence of cardiovascular disease in women increased dramatically after postmenopausal years. Compliance and distensibility are wall properties of arteries, which may play a role in cardiovascular disease. The purpose of this study was to investigate whether the influence of gender on arterial compliance in patients with hypertension (HP) and/or coronary heart disease (CHD). Methods The cohort consisted of 500 patients with HP and/or CHD who were registered as outpatients in the Department of Geriatrics of the Qi-Lu Hospital of Shandong University from February 2007 to April 2008 (age from 45 to 87 year). All subjects gave informed written consent. The study protocol was approved by the Ethics Board of Qi-Lu Hospital of Shandong University. Five hundred patients (330 men, 170 women) were divided into four groups: premenopausal women (n=54) and age-matched normotensive men (n=118), postmenopausal women (n=116) and age-matched men (n=212). Postmenopausal women did not receive hormone replacement therapy. Carotid-femoral pulse wave velocity (CF-PWV), capacitive arterial compliance (C1), and oscillatory arterial compliance (C2) were measured using Complior SP automatic device and DO-2020 cardiovascular profiling instrument. Premenopausal and postmenopausal women were compared with age-matched men. Results Postmenopausal women had lower positive rates of CF-PWV and C1 than age-matched men (44.83% vs 72.17%, p 0.05). Women with CHD, HP+CHD had lower CF-PWV (p 0.05). Moreover, women with CHD, HP+CHD had lower positive rates of CF-PWV and C1 than men (3.33% vs 36.54%, 3.33% vs 21.15%, p 0.05). In multiple regression analysis of patients with CHD, HP and CHD, CF-PWV, C1 and C2 were significantly correlated with gender (women) (r=0.480, −0.259, −0.242, p 0.05). Conclusion The effect of cardiovascular risk factors on arterial compliance was not uniform but depends on gender and menopause.

A quasi-lambda four-level system shows both electromagnetically induced absorption (EIA) and electromagnetically induced transparency (EIT). In addition to an optical coupling field and a probing field, there is a radio field which interacts with two excited state hyperfine levels of the quasi-lambda four-level system consisting of two excited state hyperfine levels and two ground state hyperfine levels. If a driving field which interacts with two ground state hyperfine levels is introduced, the quasi-lambda four-level system is modified to a closed-lambda four-level system. The behaviors of the driving field and radio field are studied in this paper and it is seen that the occurence of EIA or EIT and the whole probing properties are controlled by the Rabi frequencies of both driving field and radio field.

Using finite-difference time-domain （FDTD） method, we found the relationship between filling factor and band gap of square and hexagonal array of circular photonic crystal, and obtained the geometric parameters of the 2D photonic crystal, for which the number of bandgaps are the greater. Using FDTD method to calculate the extraction efficiency of the photonic crystals with the parameters, we verified the enhancement in extraction efficency of the GaN-based blue light-emitting diode based on the square and hexagonal array of circular photonic crystals with the the parameters, and the hexagonal arrangement is better than the square arrangement. By using the bang gap theory and equivalent medium theory was analyzed the mechanism of antireflection.

Output beam quality of InnoSlab laser with hybrid resonator is analyzed in this paper for the thermal lens effect and mirror misalignment. Many aspects, such as far-field light intensity distribution, far-field divergence angle, beam waist radius, beam quality factor M2 and PIB curve, etc, are discussed. Especially, in the off-axis unstable resonator direction, the influence of beam quality is discussed with respect to mirror misalignment by M2 and PIB curve. This gives valuable reference to unstable resonator beam quality evaluation, for which a unified standard has not been set up as yet.

Electromagnetically induced transparency (EIT) resonance is obtained in a Λ three-level configuration when the coupling field and the probe field satisfy the two-photon resonance condition. When an additional microwave field drives the transition between two low levels of the Λ three-level system the EIT is observed to split into multiple EITs. In this paper we present a theoretical study of this effect. The results show that the EIT resonance can be split into triplet and the spectral positions of EIT windows is determined by the intensity and the frequency of the microwave field. Therefore, a microwave field can be used to open more than one EIT windows and the EIT frequency tuning can be realized by controlling intensity and frequency of the microwave field.

To explore the changes of analgesic effect of combined Radix Aconiti (Ac) and Radix Stephaniae Tetrandrae (ST). Methods: Rabbits and mice were divided randomly into following groups: the blank control group, the positive control group, the Ac group, the ST group, the combined Ac:ST(1:1) group and the combined Ac:ST (1:2) group. Using chemical, heat and electrical stimuli, four kinds of pain models were established to observe the changes of pain threshold of mice before and after using combined Ac and ST therapy. Results: Remarkable analgesic effect was obtained in the positive control group and all the groups treated with Ac and ST within 3 hours ( P 0.01), and the effect was more obvious in the combined Ac ST groups and the Ac group. The analgesic effect of the positive control group, the ST and the Ac group weakened gradually 3 hours later, and disappeared after 24 hrs in the positive control group and the ST group, but it is still remarkable in the combined Ac ST group, which showed a significant difference from that in the positive control group or in the groups treated with one single herb (As or ST). Conclusion:The analgesic effect of the combined Ac ST is superior to the AC and the ST used alone.

Transforming growth factor-b 1 (TGFb1) has a diverse role in astrogliosis and neuronal survival, but the underlying mechanism remains to be elucidated, especially in traumatic brain injury (TBI). Here, we show that the expression of TGFb1 was increased in the pericontusional region, accompanied with astrogliosis and neuronal loss in TBI rats. Moreover, TGFb1 knockdown not only reduced the number of neurons and inhibited astrogliosis but also resulted in a significant neurological dysfunction in rats with TBI. Subsequently, Smad3, a key downstream signal of TGFb1, was involved in pericontusional region after TBI. These findings therefore indicate that TGFb1 is involved in neuroprotection and astrogliosis, via activation of down stream Smad3 signal in the brain after injury. Refereed/Peer-reviewed

Background: Neuraminidase inhibitors were widely used during the 2009-10 influenza A H1N1 pandemic, but evidence for their effectiveness in reducing mortality is uncertain. We did a meta-analysis of individual participant data to investigate the association between use of neuraminidase inhibitors and mortality in patients admitted to hospital with pandemic influenza A H1N1pdm09 virus infection. Methods: We assembled data for patients (all ages) admitted to hospital worldwide with laboratory confirmed or clinically diagnosed pandemic influenza A H1N1pdm09 virus infection. We identified potential data contributors from an earlier systematic review of reported studies addressing the same research question. In our systematic review, eligible studies were done between March 1, 2009 (Mexico), or April 1, 2009 (rest of the world), until the WHO declaration of the end of the pandemic (Aug 10, 2010); however, we continued to receive data up to March 14, 2011, from ongoing studies. We did a meta-analysis of individual participant data to assess the association between neuraminidase inhibitor treatment and mortality (primary outcome), adjusting for both treatment propensity and potential confounders, using generalised linear mixed modelling. We assessed the association with time to treatment using time-dependent Cox regression shared frailty modelling. Findings: We included data for 29234 patients from 78 studies of patients admitted to hospital between Jan 2, 2009, and March 14, 2011. Compared with no treatment, neuraminidase inhibitor treatment (irrespective of timing) was associated with a reduction in mortality risk (adjusted odds ratio [OR] 0·81; 95% CI 0·70-0·93; p=0·0024). Compared with later treatment, early treatment (within 2 days of symptom onset) was associated with a reduction in mortality risk (adjusted OR 0·48; 95% CI 0·41-0·56; p