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Airway inflammation and remodeling are critical pathological changes in asthma, and macrophage activation plays a vital role in this process. Sirtuin 1 (SIRT1) reduces airway inflammation by affecting macrophages in asthma. This study aimed to investigate the potential benefit and underlying mechanism of the SIRT1 agonist bergenin as a treatment for asthma. We performed in vivo and in vitro experiments by establishing a Sirt1fl/fl-LysMcre mouse asthma model and using the alveolar macrophage-like cell line MH-S, respectively. Our results show that Sirt1fl/fl-LysMcre asthmatic mice exhibited more severe airway inflammation and airway remodeling than wild-type mice. As an activator of SIRT1, bergenin attenuated asthmatic airway pathology and reduced production of interleukins 1β, IL-5, IL-6, and matrix metalloproteinase 9 (MMP-9) in wild-type asthmatic mice. However, the therapeutic effects of bergenin were significantly attenuated in Sirt1fl/fl-LysMcre asthmatic mice or following coadministration with the SIRT1 inhibitor EX-527. Further experiments showed that activation of SIRT1 by bergenin deacetylates nuclear factor κB and hinders its nuclear translocation, thereby affecting IL-1β, IL-5, IL-6, and MMP-9 production by regulating transcriptional activity. Our study suggests that bergenin can improve asthma-induced airway inflammation and remodeling by activating SIRT1 in macrophages.

This paper mainly focuses on the optimal output feedback control problem for networked control systems (NCSs) involving multiplicative noises, packet dropouts, input delays and measurement delays. ...

In order to further improve the anti-disturbance capability and reduce the conservativeness of unmanned aerial vehicle (UAV) attitude control system, a new enhanced anti-disturbance control law by combining the active disturbance rejection control with disturbance observer-based control is proposed. On the one hand, the disturbances such as external environmental disturbance and complex model nonlinearity are merged into an equivalent disturbance with bounded derivative, which is compensated by the active disturbance rejection control law. On the other hand, the disturbance observer-based control is utilized to estimate the disturbances which have the detailed priori information. The system stability analysis is given by the Lyapunov method. The numerical simulation is carried out to verify the efficiency of the proposed method.

A transmitted optical fiber sensing system based on orthogonal demodulation algorithm is used for hydrogen detection in this paper. WO3/Pt fabricated by sol–gel method was used as sensing material. WO3 film reacts with hydrogen by the catalysis of Pt and refractive index of the sensing film changed, by measuring the transmitted optical power the concentration of hydrogen can be detected. Orthogonal demodulation algorithm was used to demodulate the weak transmitted optical intensity signals. Compared with the traditional ratio-type transmitted optical fiber hydrogen sensing system, the noise reduced by 28 times. The limit of detection is 495ppm and with good repeatability and stability. In order to improve the sensitivity of the system, three pieces of sensing film were used to increase the interaction length of the sensing material with hydrogen and the sensitivity increased by 2.592 times. With the orthogonal demodulated technique and multi pieces of sensing film, high sensitivity, fast response and low cost hydrogen sensing system was implemented and is very promising for the monitoring of hydrogen leakage in the field of hydrogen production, transportation, and storage.

In this paper, an active disturbance rejection control guidance law is proposed for the problem of unmanned aerial vehicle (UAV) collision avoidance. First, a linear time-varying collision avoidance model based on a collision cone is established. Then the active disturbance rejection control guidance law is designed to ensure the security of UAV collision avoidance. In addition, the stability of a nonlinear active disturbance rejection system with an extended state observer is proved by the circle criterion, and the stability conditions are used to design the guidance coefficients. A simulation system based on a six-degrees-of-freedom UAV model is used to demonstrate the performance of this guidance law. The results conclusively demonstrate that this method can achieve collision avoidance in the presence of sensor noise, an unknown acceleration of an obstacle, and wind disturbance. Moreover, the manoeuvring range of collision avoidance using this method is narrower than the collision avoidance method based on nonlinear dynamic inversion guidance.

Aiming at the identification and classification of radar radiation sources, this paper proposes a classification method based on the Convolutional Neural Network(CNN) for radar signal classification. Firstly, this paper sets the appropriate learning rate, batch size, iteration number, momentum and weight decay coefficient. Secondly, the time domain real part waveform signal is modeled and the network structure is selected for analysis. Finally, according to the spectrogram of the time domain waveform by Short Time Fourier Transform(STFT), design two different convolutional neural network models. The results show that the network learns more distinguishing feature representations and has better generalization capabilities after STFT. The Deep Learning of CNN has a greater advantage in extracting the feature representations in the spectrogram of the radar signal.

Track quality (TQ) evaluation of tactical data link is most crucial content in track processing, and is also the basis of tactical data link. In this paper, a new assessment method is presented to calculate the TQ. At first, TQ area equation defined in the U.S. Army tactical data link formatted message standard (TADIL) 6016B is introduced. Meanwhile, according to the educing and analyzing, this paper shows that the track quality in U.S. Army data link is defined according to the ellipse expression based on the distributing, and the TQ acreage value equals to the acreage of ellipse. Moreover, a new method of distance measurement on TQ value is proposed. At last, simulations show the affection of the geography location error, radar measurement error and extrapolation error on the TQ value.

In order to measure the total cross section for thermal neutrons, a photoneutron source (PNS, phase 1) has been developed for the acquisition of nuclear data for the Thorium Molten Salt Reactor (TMSR) at the Shanghai Institute of Applied Physics (SINAP). PNS is an electron LINAC pulsed neutron facility that uses the time-of-flight (TOF) technique. It records the neutron TOF and identifies neutrons and $\gamma$-rays by using a digital signal processing technique. The background is obtained by using a combination of employing 12.8 cm boron-loaded polyethylene(PEB) (5$\%$ w.t.) to block the flight path and Monte Carlo methods. The neutron total cross sections of natural beryllium are measured in the neutron energy region from 0.007 to 0.1 eV. The present measurement result is compared with the fold Harvey data with the response function of PNS., Comment: 9 pages,10 figures

Sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy was employed to study the speciation of sulfur in raw coal, ash by-product and fine particulate matter from a small coal-burning boiler. By means of least square analysis of the XANES spectra, the major organic and inorganic sulfur forms were quantitatively determined. The results show that about 70% of the sulfur in raw coal is present as organic and a minor fraction of the sulfur occurs as other forms: 17% of pyrite and 13% of sulfate. While in bottom ash, fly ash, and PM(2.5), the dominant form of sulfur is sulfate, with the percentage of 80,79 and 94, respectively. Moreover, a number of other reduced sulfur including thiophenic sulfur, element sulfur and pyrrhotite are also present. During coal combustion, most of organic sulfur and pyrite were oxidized and released into the atmosphere as SO(2) gas, part of them was converted to sulfate existing in coal combustion by-products, and a small part of pyrite was probably reduced to elemental sulfur and pyrrhotite. The results may provide information for assessing the pollution caused by small boiler and developing new methods for the control of SO(2) pollution.

In order to further understand the sources of PM2.5 in Shanghai air, the synchrotron X-ray fluorescence microprobe at the BL-4A Beamline of Photon Factory of High Energy Accelerator Research Organization, Japan, was applied to analyze the individual PM2.5 particles collected from Shanghai air in the winter of 2007. Eight categories of emission sources were recognized in these individual particles. The source identification shows that most of the analyzed PM2.5 particles are derived from vehicle exhaust and metallurgical emissions. This suggests that the important emission sources of PM2.5 in Shanghai air would be vehicle exhaust and metallurgical activities.

The impact of coal-burning emission on sulfur in camphor leaves was investigated using Proton Induced X-ray Emission (PIXE) and synchrotron radiation technique X-ray Absorption Near-Edge Structure (XANES) spectroscopy. The PIXE results show that the sulfur concentrations in the leaves collected at the polluted site are significantly higher than those in controls. The Sulfur XANES spectra show the presence of organic (disulfides, thiols, thioethers, sulfonates and sulfoxides) and inorganic sulfur (sulfates) in the leaves. The inorganic sulfur in the leaves of camphor tree polluted by coal combustion is 15% more than that of the control site. The results suggest that the long-term coal-burning pollution resulted in an enhanced content of the total sulfur and sulfate in the leaves, and the uptake of sulfur by leaves had exceeded the metabolic requirement of plants and the excess of sulfur was stored as SO(4)(2-). It can monitor the sulfur pollution in atmosphere.

In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithms are also proposed.

The photoneutron source (PNS, phase 1), an electron linear accelerator (linac)-based pulsed neutron facility that uses the time-of-flight (TOF) technique, was constructed for the acquisition of nuclear data from the thorium molten salt reactor(TMSR) at the Shanghai Institute of Applied Physics (SINAP). The neutron detector signal, with the information on the pulse arrival time, pulse shape, and pulse height, was recorded by using a waveform digitizer (WFD). By using the pulse height and pulse-shape discrimination (PSD) analysis to identify neutrons and $\gamma$-rays, the neutron TOF spectrum was obtained by employing a simple electronic design, and a new WFD-based DAQ system was developed and tested in this commissioning experiment. The developed DAQ system is characterized by a very high efficiency with respect to millisecond neutron TOF spectroscopy, Comment: 5 pages, 7 figures

In order to explore the interaction between the expression of ZnT3 (Zinc Transporter 3) mRNA (Messenger Ribonucleic Acid) and the concentration of elemental zinc in mouse brain, zinc distribution in brain was determined by synchrotron radiation X-ray fluorescence (SRXRF) technique and a ZnT3 mRNA expression in tissue was examined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method.The results show that the zinc concentration is not evenly distributed in brain slices. Its concentrations in cerebral cortex and hippocampus are nearly 5-10 times higher than those in other positions. A corresponding relation is that ZnT3 mRNA in cerebral cortex, hippocampus and testis has higher abundant degree, but it is not examined out in other tissues. Furthermore, the results promote that ZnT3 facilitates the accumulation of zinc in synaptic vesicles and may play an important role in structuring of vesicular zinc pool.

A magneto-optical chip of Fe-(Co6Ag94) granular films was fabricated by using of combinatorial Fe ions implanting into co-sputtered Co6Ag94 films and 16 units with different Fe content were prepared via binary masking scheme. The structures and surface morphologies of as-prepared and annealed Fe-Co6Ag94 films were analyzed by X-ray diffraction and atomic force microscopy respectively. It reveals that the Co, Fe and FeCo granules precipitate, grow and then form nanoparticles embedded in the Ag matrix during annealing. In addition, the measurement of the magneto-optic polar Kerr effect shows that Kerr rotation increases with increasing Fe content, which contributes to the magnetic moment. Precipitation and growth of the magnetic granules during annealing also increase the Kerr rotation due to the size effects. Further, Mossbauer study confirms that the formation of granules with certain size plays a principal role in the enhancement of magneto-optic polar Kerr effect. (C) 2003 Elsevier Ltd. All rights reserved.

In order to evaluate the evolution of contamination we collected river water and sediment samples in the every spring season since 1998. The elemental analysis of water and sediment samples was performed by PIXE using the 3X2 MeV NEC Tandem accelerator at the Taipei Institute of Physics. The characterization of alpha- and beta-radioactive levels for water and sediment samples was performed by a BH1216, low background radioactivity instrument at the Shanghai Institute of Nuclear Research. The PIXE results showed that the elemental contents of Cl, K, Ca, Cr, Mn, Fe, Zn and Pb in river water gradually decreased with the rising tide. At high tide, their concentrations were minimum and then increased toward the ebb tide. The analysis also demonstrated that the radioactivity of water samples had been gradually decreasing year by year. It was found that the decreasing rate of alpha-radioactivity was a little quicker than that of beta-radioactivity. Further aspects of environmental data evaluation and assessment are also discussed.

This note deals with the scanning of femoral head slices from both normal and osteoporosis subjects using synchrotron radiation X-ray fluorescence (SRXRF) microprobe technique. The sample preparation and experimental apparatus are described in detail. The quantitative computerized tomography (QCT) of elemental distribution, such as Ca, P, K, Fe, Zn, Sr and Pb in bone slice tissue including cartilage, substantial compact and substantial spongy, is investigated. Combined with the correlation between P, K, Zn, Sr and Ca, the loss way of minerals and the physiological functions of some metal elements in bone are also discussed.

On account of the ease with which positron annihilation experiments may be made and the well-known manner in which positrons behave much in the way that hydrogen protons do, the positron technique is thus commonly used to study hydrogen-charging and hydrogen-absorbed metals and alloys. Indeed, the positron technique has been an indispensable and powerful tool to investigate the influence of hydrogen on microstructures and properties of materials, thus a lot of the related papers have been published. However, papers regarding the use of positrons to detect molecular hydrogen content are few in the literature. This is because hydrogen-charging of metallic materials is a quite complicated process. Generally speaking, when hydrogen-charging, the content of hydrogen increases but occasionally it becomes lower instead of higher with increasing charging time. In addition, positrons, after entering a material, are affected not only by the old defects and the newly generated defects, but by hydrogen proton screening as well. Therefore, the existence of certain relationships between the measured positron parameter and hydrogen content in the material has not been found. Among the curves of positron parameter as a function of charging time which appeared in publications, the one which has a wavelike characteristic was frequentlymore » seen. In this letter, the author found that the measured Doppler lineshape parameter happens to be roughly directly proportional to the molecular hydrogen content involved in a particular material.« less

On the base of considering the safety, reliability, economy, power quality in the power grid running and so on, the paper established a set of comprehensive evaluation indexes system for the regional power grid running state. Then it determined the evaluation indexes weight by the projection pursuit method, and defined the priority order for the evaluation objects by the theory of possibility degree and ranking in the ranking interval number method. Therefore, it constructed a comprehensive evaluation model for the regional power grid running state. After a comprehensive evaluation analysis for the power grid running state in five regions, it showed that the comprehensive evaluation indexes system and model for regional power grid running state proposed in the paper was feasible.

The influence of ?-irradiation on properties of METGLAS 2605S2 and FC3-1 Fe78B13Si9 has been investigated by M?issbauer spectroscopy and bending test. The ductility and orientation of magnetization were changed by ?-irradiation. They probably correlated with the change of microscopic free volume and release of stress in the ribbon, respectively.

This paper deals with the osteoporosis model of New Zealand rabbits in order to study the function of inorganic elements for women patients with osteoporosis. The thirty cases of iliac crest are collected and determined using neutron activation analysis (NAA). The results show that the fluorine concentrations in the experimental group are higher than those in control group and the magnesium concentrations are significantly lower (P

The speciation of iron in atmospheric particulate matter (APM) was investigated by EXAFS. APM samples with different particle sizes and from different sampling sites were collected in Shanghai, China. The chemical components of iron in the samples were calculated by the regression analysis of their EXAFS spectra. The results show that the iron in all samples mainly consists of Fe2O3, Fe3O4 and Fe2(SO4)3, however, their proportions are different in different samples.

An algorithm is presented for extracting a moving target from the background. It combines the continuity information of the target with Bayesian decision theory to segment the video images without any a priori knowledge. Experiments with an IBM-PC computer on a large number of video images have shown that this algorithm performs better than other segmentation schemes. It can be implemented for real-time operation and is especially useful for the real-time videotheodolite (RTV). >

Refractive-index (phase-contrast) radiology was able to detect lung tumors less than 1 mm in live mice. Significant micromorphology differences were observed in the microradiographs between normal, inflamed, and lung cancer tissues. This was made possible by the high phase contrast and by the fast image taking that reduces the motion blur. The detection of cancer and inflammation areas by phase contrast microradiology and microtomography was validated by bioluminescence and histopathological analysis. The smallest tumor detected is less than 1 mm(3) with accuracy better than 1 x 10(-3) mm(3). This level of performance is currently suitable for animal studies, while further developments are required for clinical application.

Our experimental results demonstrate that full-field hard-X-ray microscopy is finally able to investigate the internal structure of cells in tissues. This result was made possible by three main factors: the use of a coherent (synchrotron) source of X-rays, the exploitation of contrast mechanisms based on the real part of the refractive index and the magnification provided by high-resolution Fresnel zone-plate objectives. We specifically obtained high-quality microradiographs of human and mouse cells with 29 nm Rayleigh spatial resolution and verified that tomographic reconstruction could be implemented with a final resolution level suitable for subcellular features. We also demonstrated that a phase retrieval method based on a wave propagation algorithm could yield good subcellular images starting from a series of defocused microradiographs. The concluding discussion compares cellular and subcellular hard-X-ray microradiology with other techniques and evaluates its potential impact on biomedical research. (C) 2012 Elsevier Inc. All rights reserved.

Refractive-index (phase-contrast) radiology was able to detect lung tumors less than 1 mm in live mice. Significant micromorphology differences were observed in the microradiographs between normal, inflamed, and lung cancer tissues. This was made possible by the high phase contrast and by the fast image taking that reduces the motion blur. The detection of cancer and inflammation areas by phase contrast microradiology and microtomography was validated by bioluminescence and histopathological analysis. The smallest tumor detected is less than 1 mm3 with accuracy better than 1 × 10−3 mm3. This level of performance is currently suitable for animal studies, while further developments are required for clinical application. Refereed/Peer-reviewed