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To investigate the activation of the complement system in the retina in a mouse model of endotoxin-induced uveitis (EIU).Balb/c mice were randomly divided into control group and lipopolysaccharide (LPS)-induced EIU group. Twenty-four hours after modeling, the expressions of the major complement components of the classical pathway (CP), mannose-binding lectin (MBL) pathway, alternative pathway (AP), and terminal pathway in the retina were determined by quantitative RT-PCR. Western blotting was employed to examine the protein expressions of the key components of the complement system involved in the CP and AP pathways in the retina.s Normal mouse retina expressed a variety of complement components that were involved mainly in the CP and AP pathways. The expressions of the complement components involved in the CP and AP pathways were up-regulated in the retina of mice with EIU. Although MASP1 and MASP2 were detected in the retina in both the EIU and control groups, their expressions were weak and showed no significant difference between the two groups.The AP and CP but not the MBL pathways of the complement system are activated in the retina of mice with EIU, suggesting a role of the activated complement system in the pathological process of EIU.

Accent is a critically important component of spoken communication. In this paper, we use acoustic features with context features to detect Chinese accent, and use NaiveBayes classifier to conduct model based on ASCCD reading discourse corpus. For comparison purposes, we digitally added white noise to ASCCD, and regarded it as ASCCD (white). NaiveBayes classifier is utilized to model the acoustic feature sets, which adequately present the property of the current syllable and context. The experimental results indicate that the acoustic feature sets with context features achieve 80.7% accent detection accuracy on ASCCD. The experiment also demonstrate that the acoustic feature sets with context features achieve 75.7% accent detection accuracy on ASCCD(white). Across these acoustic feature sets, we find pitch features to be the most predictive of Chinese accent on ASCCD and on ASCCD (white).Context is important to Chinese accent detection on ASCCD and on ASCCD (white).And the experimental results show that the NaiveBayes classification has a good classification result for these.

The emerging concept of structural health management relies on extensive onboard diagnostic sensors that can provide near real-time information about the state of a structure so that informed prognostic assessment can be made of the continuing reliability of the structure. In this paper, we will discuss two types of sensing platforms that can provide valuable information about the state of a structure: 1D fiber-optic sensors and 2D thin-film sensors. Both fiber-optic and thin film sensors are easily integrated with structures, and can offer local and/or distributed sensing capabilities. Parameters that can be sensed include: static and dynamic strain, acoustic emission, vibration, corrosion products, moisture ingression etc. We will first describe some recent developments in dynamic strain sensing using optical fiber Bragg grating (FBG) sensors. Applications to detection of acoustic emission and impact will be described. In the area of chemical sensing, we will describe a nanofilm-coated photonic crystal fiber (PCF) long-period grating (LPG) sensing platform. PCF-LPG sensors can be designed to provide greater interaction between the analyte of interest and the light propagating in the fiber, thereby increasing the sensitivity of detection. Applications to humidity sensing will be described. Finally, 2D thin-film sensors on polymer substrates will be discussed. One type of sensor we have been fabricating is based on reduced graphene oxide for large-area chemical sensing applications. It is expected that these 1D and 2D sensing platforms will form part of a suite of sensors that can provide diagnostic structural health information.

Fiber-optic gas sensing techniques are commonly based on the recognition of a wide range of chemical species from characteristic absorption, fluorescence or Raman-scattering spectra signatures. By tuning over the vibrational lines of species in the path of laser beam, tunable diode laser gas sensors measure signal spectroscopic intensity, gas concentration, and other properties. However, they have limitations of bulk architecture, small change of signal on top of large background, and low sensitivity of direct absorption. Here we report the fabrication and optical measurements of tunable Er-doped fiber ring laser absorption spectroscopic sensor featuring a gas cell that is a segment of photonic crystal fiber (PCF) with a long-period grating (LPG) inscribed. The tunable laser beam is coupled into the cladding of the PCF by the LPG where the gas in air holes absorbs light. The light travels along the PCF cladding and reflects at the end of the fiber where a silver film is coated as a mirror at one end facet. The light propagates back within cladding and passes through the gas one more time thus increasing the interaction length. This light is finally recoupled into the fiber core for intensity measurement. The proposed fiber gas sensors have been experimentally used for ammonia (NH 3 ) concentration detection. They show excellent sensitivity and selectivity, and are minimally affected by temperature and/or humidity changes. The sensors using PCF-LPG gas cell are simple to fabricate, cost-effective, and are deployed for a variety of applications not possible using conventional optical fibers.

Total-Routhian-surface calculations by means of the pairing-deformation-frequency self-consistent cranked shell model have been carried out for germanium and selenium isotopes, in order to search f ...

Total-Routhian-Surface calculations have been performed to investigate the shape evolutions of $A\sim80$ nuclei, $^{80-84}$Zr, $^{76-80}$Sr and $^{84,86}$Mo. Shape coexistences of spherical, prolate and oblate deformations have been found in these nuclei. Particularly for the nuclei, $^{80}$Sr and $^{82}$Zr, the energy differences between two shape-coexisting states are less than 220 keV. At high spins, the $g_{9/2}$ shell plays an important role for shape evolutions. It has been found that the alignment of the $g_{9/2}$ quasi-particles drives nuclei to be triaxial., Comment: 12 pages, 6 figures

In this paper, analytical solutions for size-dependent static bending and free vibration of a pure 0–3 polarized PbLaZrTi (PLZT) cantilever are developed. This paper also makes the first attempt to investigate the static bending of a cantilever metal beam bonded with discretized 0–3 polarized PLZT actuator based on the modified couple stress theory and composite laminated beam theory. These models involve an internal material length scale parameter used to capture the size effect. In the limit when the internal material length scale parameter goes to zero, this model reduces to classical (local) solutions available in the literature. Exact solutions for the normalized static deflection are obtained as a function of the actuator thickness and the internal material length scale parameter. The simulations show that the size-dependent results developed by the present models have a remarkable difference with those got by the classical solutions when the ratio of the actuator thickness to the internal material length scale parameter is small. It is also observed that an increase in the stiffness parameter of the substrate beam gives rise to an increase in the effect of the material length scale parameter on tip deflections of the cantilever metal beam.

Fiber-optic accelerometers have attracted great attention in recent years due to the fact that they have many advantages over electrical counterparts because all-fiber accelerometers have the capabilities for multiplexing to reduce cabling and to transmit signals over a long distance. They are also immune to electromagnetic interference. We propose and develop a compact and robust photonic crystal fiber (PCF) Mach-Zehnder interferometer (MZI) that can be implemented as an accelerometer for measurements of vibration and displacement. To excite core mode to couple out with cladding modes, two long-period gratings (LPGs) with identical transmission spectra are needed to be written in an endless single-mode PCF using a CO2 laser. The first LPG can couple a part of core mode to several cladding modes. After the light beams travel at different speeds over a certain length of the core and cladding, the cladding modes will be recoupled back to the core when they meet the second LPG, resulting in interference between the core mode and cladding modes. Dynamic strain is introduced to the PCF-MZI fiber segment that is bonded onto a spring-mass system. The shift of interference fringe can be measured by a photodetector, and the transformed analog voltage signal is proportional to the acceleration of the sensor head. Based on simulations of the PCF-MZI accelerometer, we can get a sensitivity of ~ 0.08 nm/g which is comparable with fiber Bragg grating (FBG) accelerometers. The proposed accelerometer has a capability of temperature insensitivity; therefore, no thermal-compensation scheme is required. Experimental results indicate that the PCF-MZI accelerometer may be a good candidate sensor for applications in civil engineering infrastructure and aeronautical platforms.

Using long-period gratings (LPGs) inscribed in an endless single-mode photonic crystal fiber (PCF) and coating nanostructure film into air channels in the PCF cladding with modal transition of the LPG, we have developed a fiber-optic sensing platform for detection of chemicals. PCF-LPG possesses extremely high sensitivity to the change in refractive index and chemical selectivity by localizing binding and/or absorption events in analyte solution. In this work, we numerically and experimentally investigate the behaviors of modal transition in the PCF-LPG where the air channels of PCF cladding are azimuthally coated with two types of nanostructure polymers as primary and secondary coatings by electrostatic self-assembly (ESA) deposition technique. The primary coating does not affect PCF-LPG parameters such as grating resonance wavelengths and its intensity that can be used for sensing, but it increases the sensitivity to refractive index of chemical analytes in the air channels. The secondary coating is for selective absorption of analyte molecules of interest. Those two coatings significantly modify the cladding mode distribution of PCF-LPG and enhance the evanescent wave interaction with the external environment, leading to a highly sensitive and selective chemical sensor. The integrated sensor has potential in a variety of applications, especially for nano-liter scale measurement in situ. The functional nanostructure films which respond to different parameters can be introduced into the air channels of the PCF-LPGs as transducers with chemical selectivity. In this paper, we demonstrate a fiber-optic humidity sensor with the proposed nanofilm-coated PCF-LPG for detection of corrosion in civil infrastructural health monitoring.

The lanthanum-modified lead zirconate titanate(PLZT) actuator activated by high-energy lights can introduce actuation and control effects without hard-wired connections. A novel controlling algorithm for multi-modal vibration control of beam structures via photostrictive actuators is proposed in this paper. Two pairs of photostrictive actuators are laminated with the beams and the alternation of light irradiation is in accordance with the changing of the corresponding modal velocity direction. A binary-coded GA is used to optimize the location and size of photostrictive actuators to maximize the modal force index and guarantee the overall modal force index induced by two pairs of photostrictive actuator is positive. The control effect of multiple vibration modes of the beam under irradiation of set light intensity/variable light intensity is analyzed. Numerical results demonstrate that the method is rational and efficient, and the use of strategically positioned actuator patches can control the first two bending modes that dominate the structural vibration effectively.

Total-Routhian-surface calculations by means of the pairing-deformation-frequency self-consistent cranked shell model have been carried out for even-even germanium and selenium isotopes to search f ...

Long-period gratings (LPGs) have shown their significant promising applications in sensors owing to the attractive features that they posses such as small size, immunity for electromagnetic interference, geometric versatility, multiplexing capability, and resistance to corrosive and hazardous environments. Recent researches have revealed that LPGs written on the standard optical fibers could be used as a powerful sensing platform for structural health monitoring. In this work, we inscribe LPGs into SMF-28 optical fiber by focused-beam CO 2 laser, demonstrating as a refractive index sensor for nondestructive chemical detections in the civil infrastructures. Although evanescent-field based LPG sensors have been applied in quantitatively monitoring chemical analytes including moisture, chloride, and corrosion by-product, etc., the sensitivity, selectivity, and response time as well as thermo-stability of such sensors are still the issues for some special purposes. In order to improve those characteristics of the sensors, we propose two types of nano-film to be coated in grating region by electrostatic self-assembly (ESA) deposition processing. The primary coating does not affect on LPG transmission parameters such as resonance wavelength and its intensity that can be used for sensing, but it increases the sensitivity to refractive index change of surrounding material. The secondary coating is for selectively absorption of analyte molecule of interest. Response time of the nanofilm-coated LPG sensor is dependent on the analyte absorption and de-absorption rates as well as the thicknesses of the coating materials, which is also investigated. Multi-channel sensor system is being designed to monitor different analytes simultaneously, which is continuing to further explore the monitoring of structural health conditions through in situ measurements of corrosion in the concrete structures.

We propose that a non-thermal X-ray arc inside the remnant of Tycho's supernova (SN) represents the interaction between the SN ejecta and the companion star's envelope lost in the impact of the explosion. The X-ray emission of the remnant further shows an apparent shadow casted by the arc in the opposite direction of the explosion site, consistent with the blocking of the SN ejecta by the envelope. This scenario supports the single degenerate binary origin of Tycho's SN. The properties of the X-ray arc, together with the previous detection of the companion candidate and its space velocity by Ruiz-Lapuente et al. (2004) and Hern\'{a}ndez et al.(2009), enables us to further infer 1) the progenitor binary has a period of 4.9$^{+5.3}_{-3.0}$ days, 2) the companion gained a kick velocity of 42$\pm$30 km s$^{-1}$, and 3) the stripped envelope mass is about 0.0016($\leq0.0083$) $M_{\sun}$. However, we notice that the nature of the companion candidate is still under debate, and the above parameters need to be revised according to the actual properties of the companion candidate. Further work to measure the proper motion of the arc and to check the capability of the interaction to emit the amount of X-rays observed from the arc is also needed to validate the current scenario., Comment: 17 pages with 4 figures included, accepted to ApJ

With the advancement of the sensor network technology and cyber physical systems [2], the merging between the virtual cyber space and the real physical world is bound to happen, which will impact the lifestyle of the human being. The metropolitan area sensor networks, composed of millions of heterogeneous sensors and penetrating every aspect of the city life, provide gigantic amount of real-time information of the city, which makes it possible to reconstruct the real world in an on-line cyber space.

To explore effects of zinc on the contents of cyclin D2, cyclin-dependent kinase 4 (CDK4), and their DNA and total cellular protein in human umbilical cord blood-derived mesenchymal stem cells (hUCBMSCs).hUCBMSCs were isolated and cultured by density gradient centrifugation adherence method in vitro. At the serial subcultivation, the hUCBMSCs were randomly divided into 7 groups. In control group, hUCBMSCs were cultured with DMEM medium (containing 15%FBS). In treatment groups, hUCBMSCs were cultured with DMEM medium (containing 15%FBS plus ZnSO4.7H2O). The final concentrations of zinc were 0.5, 1.5, 2.5, 3.5, 4.5, and 5.5 mg/L, respectively. The cellular surface antigens of CD29, CD34, CD44, and CD45 at the 3rd generation of hUCBMSCs were detected by flow cytometry. MTT assay was used to detect cell activity of the 3rd generation of hUCBMSCs. The optimum concentration of zinc was selected by the results of MTT as experimental group. The cell growth curves of experimental group and control group were drown by counting cell. The cell surface antigen, reproductive cycle, and DNA content were detected by flow cytometry mothers. The contents of cyclin D2 and CDK4 were detected by Western blot method.The positive expression rates of CD29 and CD44 were more than 70% in hUCBMSCs. The cell activity of 2.5 mg/L treatment group was superior to other treatment groups, as experimental group. At 7, 14, and 28 days, the contents of DNA, total cellular protein, cyclin D2, and CDK4 of hUCBMSCs were significantly higher in experimental group than those in control group (P0.01). The percentage of hUCBMSCs at S stage and proliferation index in experimental group were also significantly higher than those in control group (P0.01).Zinc (0.5-4.5 mg/L) has the promoting effect on the hUCBMSCs activity, and 2.5 mg/L is the optimal concentration. Zinc (2.5 mg/L) can accelerate the proliferation and DNA reproduction of hUCBMSCs and increase the contents of cyclin D2, CDK4, and cellular total protein.

The array of axially aligned air channels and the robust waveguide characteristics of index-guiding photonic crystal fibers (IG-PCFs) integrated with long-period gratings (LPGs) make them a powerful platform for chemical sensing and detection. Compared to their conventional all-solid fiber counterpart, the IG-PCFs are a particularly attractive sensing device as they are both a waveguide and a vapor/aqueous transmission cell, permitting light intensity-analyte interaction over long path length without the removal of fiber cladding. While the fundamental core-mode in the IG-PCF has been utilized for evanescent field based sensing, there exist two inherent limitations: (1) only short distance extended by evanescent waves from the guiding core to the surrounding PCF cladding air channels to restrict the probing of an analyte only in the inner most ring of the air channels in cladding, and (2) less than 1% power of the core-mode overlap with the surrounding air channels leading to weak light intensity-analyte interactions due to the localization of the coremode in the fiber core area. Should a cladding-mode with maximum overlap in air channels be excited by an LPG, it would fundamentally increase the evanescent field sensitivity. In this work, we present the simulation for the mode properties of selected IG-PCF for optimization of mode field distribution and light power overlap with air channels in fiber cladding. The numerical calculation reveals that if the optimized cladding-mode is selectively coupled, the evanescent wave overlap (at wavelength of 1550 nm) with cladding air channels of the round and hexagonal structures can be increased from 0.11% and 0.13% up to 4.01% and 6.54%, respectively.

The excitation spectra of nuclei in the regions $150lAl190$ and $220lAl250$ are commonly considered as showing characteristics of the rotational motion. In the present work, however, there is evidence indicating that the nuclei can evolve from rotation to vibration. We have used two simple models to discuss the collective motions of a nucleus for different spin ranges. In addition, in order to get the insight into the rotational-like properties of nuclei, as an example, shape calculations using the total Routhian surfaces (TRS) model have been carried out for positive-parity states in $^{156}\mathrm{Gd}$. Also we have shown the result of the nucleus $^{102}\mathrm{Ru}$ which is given as an example of the reverse transition, i.e., vibration to rotation. The TRS plots reveal that, with increasing spin, the former nucleus becomes slightly soft in $\ensuremath{\gamma}$ and $\ensuremath{\beta}$ deformations, while the latter one becomes rigid in the $\ensuremath{\gamma}$ deformation.

In order to solve for the mode intensity distributions in a photonic crystal fiber (PCF) cross section and the propagation constant for the design of fiber bandpass filters, we numerically analyze the modal distributions of the fundamental core mode and different cladding modes. Based on the simulation results, we also experimentally demonstrate a simple fabrication of bandpass filters inscribed on the PCF by inserting a π-phase shift in a 12-period long-period grating (LPG). Two rejection bands with greater than 18 dB isolation and an ultra-wide band of 85.3 nm are achieved. The phase-shifted PCF-LPGs are fabricated using a CO2 laser with point-by-point focused pulses. The proposed fiber bandpass filter is compact and is not influenced by temperature effects.

Calculations based on density functional theory (DFT) have been carried out for the gas-phase ion-molecule reactions of CS 2 with CHX •- ( X = F , Cl , and Br ) to investigate the effect of the halogen-substituent on the reaction mechanism. The doublet potential energy surfaces (PESs), involving two striking reaction patterns named by the middle-C attack and the end-S attack in terms of anion attack on the C and S atoms of CS 2, have been explored and characterized in detail. Compared with the results of the end-S attack, reaction with the middle-C attack pattern displays more efficiency on PES. For a given reaction pattern, the reactions of CHCl •- and CHBr •- occur with similar efficiencies and reactivity trends. The CHF •- anion displays remarkably different reactivity, which is traced to its lower electron binding energy and the effect of the electronegative fluorine substituent. This is in good agreement with the experimental observation. According to the property of the product branching ratios in experiment, dynamical effect is used to evaluate the reason that the end-S attack with less energetically favorable obtained in our theoretical studies is comparable to the middle-C attack.

Purpose To investigate whether a synthetic LXR agonist TO901317 (TO90) ameliorates ocular inflammation in a mouse model of experimental autoimmune uveitis (EAU) and to explore its underlying mechanism. Methods EAU was induced with subcutaneous injection of IRBP161-180 peptide (SGIPYIISYLHPGNTILHVD) in B10.RIII mice. TO90 (50 mg/kg/d) or vehicle was administrated orally for successive 16 days or 8 days as prevention or effector phase, respectively. The severity of EAU was evaluated with clinical and histological scores. The levels of LXRs, NF-κB subunit p65, and an LXR target gene ABCA1 in the retina were detected with real-time PCR and Western blotting. The expressions of proinflammatory genes, including TNF-α, IL-1β, IL-6, MCP-1, IFN-γ, and IL-17, were detected by real-time PCR. IRBP-specific lymphocyte proliferation was detected by MTT. Intracellular IFN-γ and IL-17 in CD4(+) T cells were measured by flow cytometry. Results We found both LXRα and LXRβ were expressed in mouse retina. After administering TO90 orally to B10.RIII mice, the expression of LXRα but not LXRβ was upregulated in the naive mice. Compared with naive mice, LXRα expression was increased in vehicle and TO90-treated EAU mice, but the LXRβ expression was unchanged. The protein level of ABCA1 was enhanced in TO90-treated naive and EAU mice but was unchanged in vehicle-treated EAU mice, suggesting activation of LXRα by TO90 is ligand dependent. TO90-mediated activation of LXRα improved the clinical and morphological scores in EAU mice. Meanwhile, activation of LXRα decreased the expressions of proinflammatory cytokines, including TNF-α, IL-1β, IL-6, MCP-1, IFN-γ, and IL-17 in the retina. TO90 treatment inhibited IRBP-specific immune responses. The proportions of Th1 and Th17 expressing IFN-γ and IL-17 were reduced in TO90-treated EAU mice in both prevention and effector phases. Furthermore, TO90 significantly downregulated the expressions of an NF-κB subunit p65 at the protein and mRNA levels. Conclusions TO90 activates LXRα and potently attenuates ocular inflammation in EAU. Alleviation of ocular inflammation could partially result from inhibition of the NF-κB signaling pathway. TO90 reduces IFN-γ and IL-17 expression in both prevention and treatment scenarios. Our data suggest that the LXR agonist may become a novel class of therapeutic agent for autoimmune uveitis.

An innovative method based on dynamic particle swarm optimization (DPSO) algorithm is presented to demodulate the strain profile along a fiber Bragg grating (FBG) from its reflection spectrum, which is calculated by using the modified transfer matrix method. To improve the optimization performances of algorithm itself, the inertia weight of the DPSO algorithm is adjusted dynamically according to the distance between the individual particle and the global optimal particle in the current population. Then the numerical simulation and experimental verification of the reconstruction of nonuniform strain profiles are comprehensively carried out. Both the simulation examples and experimental results verify the feasibility and validity of the present method.

The Rossi X-ray Timing Explorer ({\sl RXTE}) has made hundreds of observations on three famous young pulsars (PSRs) B0531+21 (Crab), B1509-58, and B0540-69. Using the archive {\sl RXTE} data, we have studied the phase-resolved spectral properties of these pulsars in details. The variation of the X-ray spectrum with phase of PSR B0531+21 is confirmed here much more precisely and more details are revealed than the previous studies: the spectrum softens from the beginning of the first pulse, turns to harden right at the pulse peak and becomes the hardest at the bottom of the bridge, softens gradually until the second peak, and then softens rapidly. Different from the previous studies, we found that the spectrum of PSR B1509-58 is significantly harder in the center of the pulse, which is also in contrast to that of PSR B0531+21. The variation of the X-ray spectrum of PSR B0540-69 seems similar to that of PSR B1509-58, but with a lower significance. Using the about 10 years of data span, we also studied the real time evolution of the spectra of these pulsars, and no significant evolution has been detected. We have discussed about the constraints of these results on theoretical models of pulsar X-ray emission., 42 pages, 24 figures