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BACKGROUND Acute respiratory distress syndrome (ARDS) is a common acute and severe disease in clinic. Recent studies indicated that Cxc chemokine ligand 5 (CXCL5), an inflammatory chemokine, was associated with tumorigenesis. The present study investigated the role of the CXCL5/Cxc chemokine receptor 2 (CXCR2) bio-axis in ARDS, and explored the underlying molecular mechanism. MATERIAL AND METHODS The pathological morphology of lung tissue and degree of pulmonary edema were assessed by hematoxylin-eosin staining and pulmonary edema score, respectively. Real-time PCR and Western blot analysis were performed to detect the expression levels of CXCL5, CXCR2, Matrix metalloproteinases 2 (MMP2), and Matrix metalloproteinases 9 (MMP9) in lung tissues. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the expression levels of CXCL5 and inflammatory factors (IL-1s, IL-6, TNF-alpha, and IL-10) in serum. RESULTS The results demonstrated that diffuse alveolar damage and pulmonary edema appeared in lipopolysaccharide (LPS)-induced ARDS and were positively correlated with the severity of ARDS. In addition, CXCL5 and its receptor CXCR2 were overexpressed by upregulation of MMP2 and MMP9 in lung tissues of ARDS. In addition, CXCL5 neutralizing antibody effectively alleviated inflammatory response, diffuse alveolar damage, and pulmonary edema, and decreased the expression levels of MMP2 and MMP9 compared to LPS-induced ARDS. CONCLUSIONS We found that CXCL5/CXCR2 accelerated the progression of ARDS, partly by upregulation of MMP2 and MMP9 in lung tissues with the release of inflammatory factors.

Objective To reveal the correlation between APACHE III score and sleep quality in patients in the intensive care unit (ICU). Methods This prospective, observational study included patients aged ≥18 years, who had been admitted to an integrated ICU for ≥48 h. Age, sex, Pittsburgh Sleep Quality Index (PSQI) prior to ICU, Numeric Rating Scales (NRS), noise, illumination, number of nursing interventions, Richards Campbell Sleep Questionnaire (RCSQ), and APACHE III score during sleep were evaluated. Results A total of 124 ICU patients were included, all with APACHE III scores Conclusion In ICU patients with APACHE III scores below 60 points, APACHE III score was not associated with sleep quality. PSQI score prior to ICU and noise were significantly inversely associated with sleep quality in this ICU patient population.

Three new saponins (1–3), a new natural product (4) and six other known compounds (5–10) were isolated from the whole Reineckia carnea plant. Their structures were established by comparison of their NMR spectra and MS data with literature data. In addition, all the isolated compounds were evaluated in vitro for anti-inflammatory activities against LPS-stimulated nitric oxide (NO) production in RAW 264.7 macrophages. Compounds 1–4 exhibited anti-inflammatory activities with IC50 values of 37.5 µM, 31.4 µM, 34.6 µM, and 56.1 µM, respectively. Furthermore, compounds 5–10 showed anti-inflammatory activities with IC50 values ranging from 20.3 to 42.9 µM.

To analyze the laboratory diagnosis results and epidemiological characteristics of imported malaria cases in Chongqing Municipality in 2015.According to the Standard Operating Procedures of Malaria Diagnosis Reference Laboratory Manual, all the blood samples collected from the imported malaria patients were detected by microscopy, RDT and nest PCR. Meanwhile, the epidemiological data of the malaria cases were collected from the Parasitic Diseases Information Management System and analyzed.Totally 31 cases of imported malaria were reported in Chonqing Municipality in 2015, among which, there were 2 vivax malaria cases (6.45%), 23 falciparum malaria cases (74.19%), 5 ovale malaria cases (16.13%), 1 malariae malaria case (3.22%). For the 5 ovale cases, three of them were confirmed asAll the malaria cases in Chongqing in 2015 are imported, no local cases have been found, which suggests that this municipality still maintain the malaria elimination state. However, the monitoring and management of imported malaria cases as well as the training on malaria control for related medical staff still need to be strengthened.

Additional file 7: Table S3. Primers used in this study.

Additional file 5: Table S1. Strains used in this study.

Additional file 6: Table S2. Plasmids used in this study.

We used first-principles calculations to investigate the photo-induced electron transfer (PIET) process of the hemicyanine-(TiO2)(n), complex ((TiO2)(n)-dye) for n=5, 9, 15. The geometries of the (TiO2)(n)-dye in the ground state were optimized using density functional theory (DFT) and their excited states were investigated using the time-dependent OFT (TDDFT) method. The excited energies, which were calculated using the long-range-corrected functionals, CAM-B3LYP and omega B97X-D, were in good agreement with the experimentally observed values. The wave functions based on DFT were used to calculate the charge transfer integrals by the generalized Mulliken-Hush (GMH) approach. In addition, the photo-induced charge separation rate constant (k(CS)) and charge recombination rate constant (k(CR)) were calculated using Marcus theory. The calculated results showed that there were a cascade of electron transfer channels from the dye into the (TiO2) cluster, which increases the k(CS) value. In contrast, the single channel of charge recombination decreases the k(CR), value, which is negligible compared with k(CS), indicating that electron recombination is not favored.

Long term trajectory prediction of a flying vehicle is to estimate the position in the upcoming task procedure. For extratmosphere vehicles that have the ability to track and pursue other vehicles, due to its autonomous maneuver and high mobility, long term trajectory prediction is very difficult. In this paper, a trajectory prediction method for pursuing vehicles based on advanced guidance law recognition is proposed. With the behavioral characteristic of pursuing vehicle recognized and exploited, the proposed method is able to make long term trajectory prediction more precisely than existing methods that does not utilize guidance law recognition. Digital simulation results proved the correctness and effectiveness.

Additional file 2: Table S1. Homologous amino acid sequences of Esi protein.

Additional file 6: Table S4. Primers used in RT-qPCR.

Additional file 7: Table S2. Primers used in this study.

Additional file 6: Table S1. Strains and plasmids used in this study.

Additional file 5: Table S3. Primers used in construction of vectors and mutant strains.

Additional file 4: Table S2. Strains and plasmids used in this study.

Recognition of guidance law on non-cooperative vehicle is drawing research interest among the literature, while insufficient accuracy of modeling and measurement makes it a hard problem. In this paper, a Frequency Divided Adaptive Kalman Filter is proposed to implement guidance law recognition. In FD-AKF, a Low Pass Filter is applied to extract the noise directly from state vector and measurement vector, and estimate the co-variance matrices of observation noise and prediction noise online. Without intertwined iterating equation of prediction noise and observation noise, FD-AKF decouples the estimation on prediction noise and observation noise, and thus avoids the risk of bias and divergence. Simulation results show that, FD-AKF improves robustness of guidance recognition significantly over Kalman Filter and Sage-Husa.

Tetrathiafulvalene (TTF) is a kind of fused ring aromatic compound containing four sulfur atoms in one molecule, which is well known as a charge transport material. In order to calculate the charge mobility of this semiconductor, Marcus electron transfer theory and the embedded model, which can give small intramolecular reorganization energies, were employed. The calculated results were in good agreement with the experimental values, so the above computing model is appropriate to assess the electrical property of TTF. On this basis, we predicted the charge mobility of 2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6- tetrathiapentalene (BDH-TTP) crystals, for which the molecular structure is similar to TTF. The calculated results indicated that BDH-TTP is a p-type material, which has a better performance than TTF in hole transfer due to larger hole coupling and the smaller hole injection barrier. In addition, the direct coupling (DC) and the site energy correction (SEC) methods were used to calculate the charge transfer integrals. Although the results were slightly different, the qualitative trends were the same. Furthermore we took into account the anisotropic transfer properties of TTF and BDH-TTF, since obviously the mobilities along one dimension are larger than those along three dimensions. Finally, natural bond orbital analysis was used to study the interactions in all of the dimers.

The temperature-resilient, high tensile-strength fiber poly(p-phenylene benzobisoxazole) (PBO) is light-unstable and it degrades under ultraviolet radiation. In this paper we study the photolytic mechanism of the PBO monomer, 2-phenylbenzo(d)oxazole (PO). Following absorption of a photon and excitation into the first excited state (S1), the molecule overcomes an energy barrier of 25.59 kJ·mol - 1 to enter the transition state; the oxazole ring is then opened and both benzene rings form a dihedral angle of about 90° to obtain the product, which undergoes further addition reaction with water. Calculations reveal that ring-opening is easily achieved in the potential surface of S1. However, the pathway through which the oxazole ring opens in the ground state remains obscure. The topological properties of these compounds are in good agreement with the expected bond orders and the photolytic mechanism.

A theoretical calculation of MP2/6-311++G** and MP2/aug-cc-pVDZ was used to predict the single-electron lithium bond system of H–Be⋯Li–Y (Y = H, OH, F, CCH, CN and NC). The results confirmed H–Be and Li–Y could interact to form the complexes I (HBe⋯Li–H), II (HBe⋯Li–OH), III (HBe⋯Li–F), IV (HBe⋯Li–CCH), V (HBe⋯Li–CN), and VI (HBe⋯Li–NC). The binding energies for these complexes ranged from −22.06 to −27.69 kJ mol−1 at the CCSD(T)/aug-cc-pVDZ//MP2/aug-cc-pVDZ level. Complex strength was in the order I

Figure S2. PCR amplification of the junction regions between the seven epothilone-modules. Genome templates for each PCR sample are as follows: 1, M. xanthus DZ2; 2, M. xanthus ZE5; 3, M. xanthus ZE9; 4, M. xanthus ZE14; 5, S. cellulosum So0157-2; 6, distilled water; M, DNA Marker DL2000 plus II.

Table S3. Primers used in this study.

Table S1. The insertion sites of the epothilone genes and the production of epothilones in different transposition recombinants.

Figure S1. Diagram for the construction of the CAT reporter gene vectors. The epop and aphII promoters were linked to p15A to generate p15-epop-cat and p15A-aph-cat, respectively. Then, the IR-Tpase-IR or Mx8 attp element was subcloned to each of the two plasmids above, respectively, to build the four final plasmids pTp-epoP, pMx8-epoP, pTp-aph and pMx8-aph, which were initiated by aphII and epoP, respectively. The plasmids were electroporated into M. xanthus to assay the promoter activities.

Table S2. Significantly up- and down-regulated Myxococcus genes in different recombinants.

ZnO nanorods are successfully synthesized by annealing the precursors in argon with the chemical precipitation method. The structural and optical properties of ZnO nanorods are investigated. As annealing temperature increases, the intensity of the green emission increases while the intensity of the yellow emission decreases. The result suggests that the green emission depends strongly on the annealing temperature.

We have investigated the microstructures of GaN films laterally epitaxially overgrown (LEO) on Si(111) substrates using hydride vapour phase epitaxy. The threading dislocation density in the LEO GaN is reduced by about two orders. Different etching angles of the two sidewalls of SiO2 masks (66o and 90o) lead to the asymmetry of the LEO and cause the particular microstructures of LEO GaN. In micro-Raman spectra, the intensities vary weakly periodically about 5 µm perpendicular to the mask stripes. The indistinct selective growth in the top surface is discussed.

PbSe films were grown on (111)-oriented BaF2 substrates by using molecular beam epitaxy. High resolution x-ray diffraction characterization showed good crystalline quality of PbSe films. Both longitudinal optical phonon at 135 cm-1 and transverse optical phonon at 47.6 cm-1 were observed by Raman scattering measurements. The Raman tensor calculation demonstrates that both transverse-optical and longitudinal-optical (LO) phonons in PbSe crystal are Raman active on (111)-oriented surface. Furthermore, 2LO phonon at about 270 cm-1 and polaron at about 800 cm-1 in PbSe, were also observed. The observed Raman frequencies are in good agreement with theoretical calculations using point ion model.

Hydrogenated amorphous silicon carbide (a-SiC:H) films were grown by using an organic source, xylene (C8H10), instead of methane (CH4) in a conventional plasma enhanced chemical vapor deposition system. The optical band gap of these samples was increased gradually by changing the gas ratio of C8H10 to SiH4. The film with high optical band gap was soft and polymer-like and intense photoluminescence were obtained. Room temperature electro-luminescence was also achieved with peak energy at 2.05 eV (600 nm) for the a-SiC:H film with optical band gap of 3.2 eV.

Blocked impurity band (BIB) detectors, developed from extrinsic detectors, have long been employed for ground-based and airborne astronomical imaging and photon detections. They are the state-of-the-art choice for highly sensitive detection from mid-infrared to far-infrared radiation. In this work, we demonstrate the existence of an interfacial barrier in blocked impurity band structures by evidence of temperature-dependent dark currents, bias-dependent photocurrent spectra and corresponding theoretical calculations. The origin of the build-in field is studied. The temperature-dependent characteristics of space charge effects are also investigated in detail. It is found that at higher temperature (T 14 K), the space charge influence is negligible, and the interfacial barrier is mainly caused by bandgap narrowing effects. Based on interfacial barrier effects, a dual-excitation model is proposed to clarify the band structure of BIB detectors. The photocurrent spectra related to the two excitation processes, i.e., the direct excitation over the interfacial barrier and excitation to the band edge with subquent tunneling into blocking layer, are successfully extracted and agree reasonably well with the calculated band structure results. The effects of interfacial barrier on the photocurrent spectrum, peak responsivity and internal quantum efficiency of the devices are investigated. With the consideration of interfacial barrier effects, the calculated peak responsivity shows good agreement with the experimental result. It is suggested that interfacial barrier effects should be considered for successfully designing the BIB detectors. Additionally, the build-in field is found to equivalently lower the critical field for impact ionization. This study provides a better understanding of the working mechanism in BIB detectors and also a better device optimization.

Variations of pressure along the vertical direction in a cylindrical silo are measured, of which the side wall is comprised of two separated up and down parts. The deviation of the measured results from the so-called Janssen model of silo stress is discussed. The measurements show that certain deviations from the model are always observed, no matter whether the slowly downward motion of silo bottom by “fully mobilized friction” as suggested by Vanel et al is carried on. Moreover without mobilizing the friction, the deviation may increase considerably if a tiny sink of the upper side-wall caused by weight of filled grains is present. The effect can be however eliminated by the friction mobilized. These indicate that distributions of grain weight at the bottom and lateral wall are complex and variant, and dependent on preparation manner and deformation of experiment setup. So stress boundary conditions need to be taken into account in the nonlinear elastic theory for analyzing static stress distribution of granular matter.

The two-photon absorption coefficient spectra of indirect transitions in silicon have been measured using a picosecond Nd:YAG pulsed laser pumped optical parametric generator, whose wavelength being tunable. By employing the pulsed laser with the photon energy less than the indirect energy gap of silicon, the photovoltaic response between two electrons of the silicon photovoltaic diode has been detected significantly. The peak intensity of the pulsed photovoltaic response shows a quadratic dependence on the incident intensity. This suggests a typical two photon absorption process. A relationship between the pulsed photovoltaic response and the incident intensity has been established with an equivalent RC circuit model to derive the two-photon absorption coefficient, and the spectra can also be obtained by turning the incident wavelengths. The results show that when the incident photon energy change from 0.689 eV to 0.912 eV, the two-photon absorption coefficient increase form 0.42 cm/GW to 1.17 cm/GW. The mechanism for the two-photon absorption coefficient increasing with the incident photon energy can be attributed to the electrons excited from valance band finding an increasing availability of conduction-band states as the photon energy increase from Eig/2 to near Eig. This photon frequency dependence of the two-photon absorption coefficient has been fairly interpreted by the Dinu model.

The standard diffusion length （Lp） test procedure is apt to damage the p-n junction, so we often use characteristic decay length （L） obtained by laser beam induced current （LBIC） instead of Lp. Two dimensional modeling is used to get the relations of L and Lp. Calculated L/Lp ratio is about 1.1, and it is not affected by doping concentration, Shockley-Read-Hall （SRH） lifetime and mobility. For HgCdTe photodiodes, we get characteristic decay length from the LBIC experiment, and get the true diffusion length by division by the ratio 1.1.

The effects of absorption layer parameters and hetero-interface charge on photoresponse of long-wavelength HgCdTe photodiode have been studied. The correlations between thickness of absorption layer and absorption length and diffusion length are investigated. An empirical formula is proposed to estimate the optimal thickness of absorption layer. Our theoretical investigations indicate that, when the wavelength of incident light is longer than the cut-off wavelength, the photoresponse monotonically increases with the increase of absorption layer thickness, and saturates subsequently. The wavelength of the maximal photoresponse increases with the increase of absorption layer thickness, and tends to shift toward long wavelength region. The optimal absorption layer thickness increases with increasing minority carrier life time and wavelength of incident light. It is found that the positive interface charge can induce a p-n junction at the substrate interface and significantly reduce the photoresponse. By using the metal-oxide-semiconductor diode model, possible physics mechanisms are investigated, and an approach is proposed to reduce the effects of hetero-interface charge on the photoresponse.

The Franz-Keldysh effect in the two-photon absorption process in the space charge region of an Hg0.695Cd0.305Te photodiode is demonstrated. By employing as the exciting light source a pulsed laser beam at λ0=7.92μm from an optical parametric generator and difference frequency generator pumped by a pico-second Nd:YAG laser, the photo-response has been measured as a function of the excitation intensity. The peak intensity of the pulsed photo-response shows a quadratic dependence on the incident intensity. A relationship between the pulsed photo-voltage and the incident optical intensity has been established with an equivalent RC circuit model to derive the degenerate single beam two-photon absorption coefficient. The results show that the two-photon absorption coefficient within the space charge region of the photodiode is about a factor of 2.7 higher than that outside the space charge region, implying an electric field induced enhancement of the two-photon absorption. This indicates that the Franz-Keldysh effect exists not only in the one-photon absorption process but also in the two-photon absorption process.

The performance of two-color middle wavelength photovoltaic HgCdTe detector is simulated numerically for design optimization. Three recombination mechanisms (radiation, Auger, and Shockley-Read-Hall(SRH)recombination), trap-assisted tunneling, and band-to-band tunneling are considered in two-dimensional model. The tunneling through barrier layer is calculated by transfer matrix method. The n-p-p-p-n structure is designed in simultaneous mode. The effect of SRH recombination electron lifetime in p-region on spectral response is examined, and the dependence of crosstalk on composition gradient of barrier layer is analyzed. Simulation results show that the quantum efficiency decreases rapidly with decrease of SRH electron lifetime in p-region,and at least about 10ns of SRH electron lifetime is essential for good performance of the detector. Crosstalk decreases to the steady value determined by optical crosstalk as the composition gradient of barrier layer increases to about 0.03, so critical composition gradient of about 0.03 is necessary for suppressing the electrical crosstalk.

A study of the carrier transport performance of GaAs/AlGaAs very long wavelength quantum well infrared photodetectors (peak wavelength: 15 μm; period: >40) has been carried out based on quantum wave transport theory. It was shown that the thermoexcitation effect dominates in the devices. By the current continuity and self-consistent calculation based on Schrdinger equation and Poisson equation, we found that the main feature resulting from the model is the redistribution of the carriers and the electric field along the whole structure being made uneven to maintain current conservation. The high-field region extends over a few barriers near the emitter contact, which takes up a considerable part of the applied voltage. The conventional flat band model assumes that the applied voltage drops linearly across the structure, leading to the numerical value of dark current to be far from the experiments, especially at small bias. The numerical result of self-consistent calculation well explains the measurement data.

A two-dimensional (2D) metal (Copper) sphere array is designed for the optical coupling of 9.5μm long-wavelength quantum well infrared photodetectors (LW-QWIPs). The optical coupling is studied based on Huygens' principle. It was shown that a metal sphere array with 3μm period and 0.9μm radius can reach optimal optical coupling for the 9.5μm LW-QWIPs. The maximal quantum efficiency hits 66%, which is highly superior to the conventional 45° angle coupling. The theoretical results provide detailed guidelines for 2D metal sphere array optical coupling for 9.5μm LW-QWIPs.

This paper reports the fabrication of ZnMnO semiconductor by high-dose Mn impla ntion. We studied the influence of implantation dose and annealing on its optica l properties. The broad band at 575cm-1 in Raman spectrum is attribut ed to defects related to high-dose Mn implantion. The vibration modes at 528cm-1 are considered to be associated with Mn impurities. Room temperature photoluminescence spectra show that the high-dose Mn implantion can enhance the intensity in visible band.

In this paper, the band profiles of HgCdTe (MCT) heterojunctions with the configuration of wide/narrow gap-p on narrow/wide gap-n are calculated, respectively. In the theoretical model employing a valence band offset, a new simple carrier density approximation is proposed to include the carrier degeneracy and conduction band non-parabolicity in the calculations. The effects of the location of p-n junction (zB) and the interface charge density (Q) on the band profiles of MCT heterojunctions are studied systemically, which is found to be significant and can't be neglected. With the help of the results of above research, the optimal design related to zB and Q is obtained.

Using the material chip technology,large area photodiodes of n-on-p structure with different boron implantation dose are fabricated on the Hg1-xCdxTe film for mid-infrared wavelength region(x=0.291).Current-voltage characteristics of the photodiodes are measured at 77K and zero bias resistance-area products of different photodiodes are fitted from the data in the voltage range of -0.2—0.08V.The study indicated that the R0A products of different elements depended distinctly upon the implanted boron dose.A large R0 value has also obtained in another chip with x=0.2743.All the samples in this study are grown by Riber 32P molecular-beam epitaxy system and all the junctions-forming process is same to the standard planar technology but using a series of metallic masks during the boron ion implantation.

We have studied the carrier concentration and the mobility in GaN expitaxial thin films deposited on sapphire substrate using infrared reflection spectroscopy. By theoretical calculation and fitting with the experimental IR reflection spectra for a series of Si-doped GaN epilayers and the sapphire substrate, we obtain the phonon vibrating parameters and plasmon frequency and damping constant in GaN. The carrier concentration and mobility have been deduced. The results show that the data for carrier concentration coincide with Hall measurement while the mobility is lower than Hall data by a factor of about 0.5. The variation of the LO phonon-plasmon coupling mode with doping level has been clearly observed. Raman measurement has been performed on the same series of samples, showing that the behavior of the LO phonon-plasmon coupling mode is similar to that in IR measurement.

Microstructure and adhesion properties of nitrogen-doped diamond-like amorphous carbon (DLC) film deposited by r f plasma-enhanced chemical vapor deposition method is studied by atomic force microscope, Auger electron spectroscopy (AES) and micro-indentation analysis. Results show that, with the increase of nitrogen content, particles of tens of nanometer in size appear in the film. The atomic lateral force microscope and AES analyses show that these nano particles are nitrogen-rich amorphous carbon nitride CNx, where x is larger than 0.126. Micro-indentation measurement shows that this DLC/CNx nano-composite structure reduces the residual stress of the film and improves the adhesion between DLC film and Si substrate.

The infrared spectra of PrBa2Cu3O6+x (x=1, 0.3) ceramics and films with c-axis orientation are reported in this paper, and the phonon modes in c-axis and ab-plane are distinguished by treating the different vibrational behaviour for film and ceramic samples. Due to the fact that PrBa2Cu3O6+x possesses the similar crystal structure as RBa2Cu3O6+x (R=Y and other rare earth elements), by comparing the phonon spectra, espeacially the B1u (x=1), Eu and A2u (x=0.3) modes of Pr, Y and other rare earth elements, it is found that the valence value of Pr depends on the oxygen content, i.e., the Pr valence is 3+ in PrBa2Cu3O6.3 while it is larger then 3+ in PrBa2Cu3O7.

The micro-photoluminescence(μ-PL) scan has been performed on a single V-groove GaAs/AlGaAs quantum wire in the direction perpendicular to the wire.The variatio n of μ-PL spectra from various quantum structures with different spatial positi ons has been observed.In the region of quantum wire (QWR) the PL spectra contain the peaks from QWR,necking quantum well (NQWL) and vertical quantum well (VQWL) ,while in the area about 1μm and farther away from the QWR the PL spectra show the peaks from side-wall quantum well (SQWL) and top quantum well (TQWL).All the scanned PL spectra have been fitted by Gauss line shape.The asymmetric PL peaks of QWR and SQWL were decomposed into two components which were ascribed to the optical transitions between the electron ground state in the conduction band and the heavy hole and the light hole ground states in the valence band.The variati on of PL intensity from luminescent components with the spatial positions direct ly demonstrates the origin of the photoluminescence relating to different quantu m structures,and reflects the carrier transfer from SQWL to QWR,resulting in th e PL quenching of SQWL.