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Previous studies have evaluated treatment efficacy of various antibiotics for patients with mild-to-moderate scrub typhus (ST). However, the efficacy of different antibiotics for treating severe ST remains uncertain.A retrospective study of patients with severe ST was undertaken in China. The treatment efficacy rates of doxycycline, azithromycin and chloramphenicol were compared, using treatment failure and time to defervescence as primary outcomes.In total, 876 patients with severe ST who initially received doxycycline, azithromycin or chloramphenicol were recruited. The treatment failure rate did not differ significantly between patients receiving doxycycline and patients receiving azithromycin (6.0% vs 11.4%; P=0.109). However, a higher treatment failure rate was observed for chloramphenicol compared with doxycycline (14.6% vs 6.0%; P=0.004). No significant difference in time to defervescence was observed between patients receiving doxycycline, azithromycin or chloramphenicol. Further subgroup analysis revealed a higher risk of treatment failure for chloramphenicol compared with doxycycline in patients with acute kidney injury, pneumonia and shock; and a higher risk of treatment failure for azithromycin compared with doxycycline in patients with meningitis. Significant correlation was found between azithromycin resistance and meningitis (P=0.009), and between chloramphenicol resistance and acute respiratory distress syndrome (ARDS) (P0.001) using Cramer's V correlation coefficient. Multi-variate Cox regression analysis revealed significant associations between time to defervescence and presence of ARDS, shock, myocarditis, meningitis and acute kidney injury.Azithromycin and doxycycline were found to have significant therapeutic effects in patients with severe ST. In contast, chloramphenicol was less efficacious for the treatment of these patients.

Wenzhou mammarenavirus (WENV) is a zoonotic pathogen newly discovered in east and southeast Asia. WENV has been found in wild rodent animals around the world while its standing is barely understood in Guangzhou city, where is known as a region of outbreak hotspot for zoonotic emerging infectious diseases. To investigate the prevalence and genomic characteristics of mammarenavirus in Guangzhou City, lung tissue samples from wild rodent species were collected from five districts of Guangzhou City in the year 2015 and 2016. The viral RNA was extracted and then subjected to mammarenavirus-specific PCR. The result revealed approximately 1.0% (3/306) nucleic acid positivity for lung tissue samples obtained from three rodent species: Mus musculus, Rattus flavipectus, and Rattus norvegicus. Viral metagenomic sequencing of three samples was then carried out and two full segment L and three full segment S sequences were obtained. Phylogenetics analysis indicated the sequences of the new mammarenavirus strain have 76.2% - 94.4% similarity to known WENV encoded genes, with the highest similarity to the WENV 9–24 strain. Population structure analysis grouped all known WENV into seven lineages, and this WENV Guangzhou strain was grouped with WENV 9–24 as well. Though the seroprevalence result was not available, our data provides the first nucleic acid evidence of circulating WENV in Guangzhou city, and it suggested WENV had a broader host tropism than previously known.

La correcta medicion de los parametros de las plumas es una cuestion clave para garantizar la calidad de la fabricacion de volantes de badminton. Sin embargo, la deteccion manual sigue siendo el principal metodo de medicion de parametros utilizado en la actualidad. Por eso, este estudio propone un principio de diseno y un metodo de medicion, mediante una estructura basica con una sola camara multi-sistema para la medicion de parametros. En primer lugar, sobre la base del principio de imagen en lente convexa, con el dispositivo de medicion propuesto, se tomaron las imagenes de las plumas dentro de un espejo a diferentes angulos. Se obtuvieron tambien las formulas para medir su curvatura, caida, ancho y espesor. En segundo lugar, se analizo la relacion entre la caida y la profundidad de campo. El analisis indico que todas la plumas con diferentes niveles de caida debian situarse dentro de los limites de la profundidad de campo para asegurar que la camara obtenia imagenes claras. Por ultimo, los valores medidos se compararon con los resultados obtenidos por medicion manual con un calibre normal. La curvatura, caida, espesor y ancho de los trozos de pluma pueden medirse con el dispositivo propuesto de una sola camara segun los resultados practicos obtenidos. Los resultados de este estudio pueden servir como referencia para aumentar el rendimiento y la calidad de la pluma de badminton y reducir el coste del dispositivo y los errores humanos. Keywords: imagen digital de pluma, espejo plano, curvatura y caida, medicion de parametros

Owing to high critical temperature (125 K) and high upper critical field, TlBa2Ca2Cu3O9 (Tl-1223) superconductor is a kind of superconducting power transmission material working at liquefied natural gas temperature, and it has a great potential application value in the strong and weak electric field. In this work, the Tl-1223 superconducting films are fabricated by rapidly heating-up sintering technology (RHST) on (00l) lanthanum aluminate substrates. The Tl-Ba-Ca-Cu-O target is used as a sputtering source to deposit the precursor films by the radio-frequency magnetron sputtering technique. The Tl-contained pellets, named annealing targets, are fabricated by the solid-state reaction of stoichiometric quantities of Tl2O3, BaO2, CaO and CuO powders with an initial cation ratio of m Tl:Ba:Ca:Cu=0.4-1.8:2:2:3. The amorphous precursors together with the annealing target providing Tl source are sealed in a silver foil and annealed at 820℃ for 5 min in argon atmosphere, then converted into Tl-1223 superconducting phase. The heating rates are set at 2.5℃/s from room temperature to 350℃, 5℃/s from 350℃ to 650℃, and 35℃/s from 650℃ to 820℃, respectively. The prepared films are characterized by X-ray diffraction and scanning electron microscope. In the conventional low heating rate process, all of the precursor films sintered together with the annealing targets containing different Tl content are first converted into Tl-2212 superconducting phase. That is because the sample residence time in the phase transition temperature range of Tl-2212 is longer, while the phase-formed temperature of Tl-2212 is lower than that of Tl-1223. In the RHST, when the metal ion molar ratio of Tl to Ba in the annealing target is 1.8:2, the main phase of the film is (00l)-oriented Tl-2212. In addition, the film also contains a small number of Tl-2223 grains. On reducing the ratio to 1:2, the film is composed of Tl-1212, Tl-2212, Tl-1223 and Tl-2223 grains. As the ratio decreases to 0.8:2, the film contains the (00l)-oriented Tl-1223 grains and traces of Tl-2223 grains. With the ratio decreasing to 0.4:2, purely c-axis oriented Tl-1223 film is obtained. The critical transition temperature Tc onset of the as-grown film is only 103 K. The film annealed again in oxygen gas has a dense crystal structure and excellent electrical properties. The Tc onset of the sample is about 116 K, and the critical current density Jc is about 1.5 MA/cm2 (77 K, 0 T). The experimental results show that the new sintering process to grow Tl-based films has several advantages such as the short processing cycles, less raw-material consumption, and low production cost.

Sphingosylphosphorylcholine (SPC) is a naturally occurring bioactive sphingolipid in blood plasma, metabolizing from the hydrolysis of the membrane sphingolipid. It has been shown to exert multifunctional role in cell physiological regulation either as an intracellular second messenger or as an extracellular agent through G protein coupled receptors (GPCRs). Because of elevated levels of SPC in malicious ascites of patients with cancer, the role of SPC in tumor progression has prompted wide interest. The factor was reported to affect the proliferation and/or migration of many cancer cells, including pancreatic cancer cells, epithelial ovarian carcinoma cells, rat C6 glioma cells, neuroblastoma cells, melanoma cells, and human leukemia cells. This review covers current knowledge of the role of SPC in tumor.

The fan-beam optical sensor is made up of many semiconductor lasers and detectors fixed around the wall alternately at a cross section of pneumatically conveying pipe. When the sensor works, a scanning light source emits a 50° lamellar fan-beam through the gas-solid two phase flow, and the projection data resulting extinction effect of solid particles are detected at the same time. With the projection data, the flow rate mass can be calculated, and then the flow image can be reconstructed. In this paper, the design of the sensor including spatial arrangement of the structural parts, basic principle and measurement sensitivity distribution are introduced. The mathematical measurement model of solid mass flow rate is presented together with the testing results.

Concerning the recognition of feather quill crease feature,a new feature extraction method was proposed.In order to solve the scaling and translation sensitivity of Radon transform,an improved Radon transform was used to extract moment invariants of target region and local projection technology was adopted to eliminate interference physiological texture of feather quill.Obtaining invariants matrix by changing the scale factor,Singular Value Decomposition(SVD) was provided here to obtain feature invariant for classification and recognition.The results show that this suggested method has higher robustness and higher recognition rate compared with other algorithms.

We investigate the self-emissions from serial high-temperature superconductor bicrystal Josephson junction arrays embedded in a quasi-optical resonator. A bicrystal substrate is used as a dielectric resonator antenna, which increases the coupling strength between the junction array and the electromagnetic (EM) wave. Both three-dimension (3D) electromagnetic simulations and experiments are performed. Strong off-chip radiations are measured from the junction array at 78 GHz and 78 K. The proposed method and the experimental results are important for millimeter wave applications in junction arrays.

The double-side Tl2 Ba2 CaCu2O8 (Tl-2212) superconducting thin films were fabricated on CeO2 buffered sapphire substrates. The reactive magnetron sputtering technique was used to grow CeO2 buffer thin films on sapphire substrates. Making use of the metal cerium as a sputtering source, the depositing rate is much higher compared with the CeO2 target. The Tl-2212 thin films on CeO2 buffered sapphire substrates were fabricated by a dc magnetron sputtering and post-annealing process. The x-ray diffraction indicates that the thin film is pure Tl-2212 phase with the c-axis perpendicular to the substrate surfaces, and epitaxially grown on the CeO2 buffered sapphire. The critical transition temperature Tc is around 106K, the critical current density Jc is around 3.5MA/cm2 at 77K, and the microwave surface resistance Rs at 77K and 10 GHz of the film is as low as 390 μΩ.

The experimental results of mm-wave coherent emission from a high temperature superconducting bicrystal Josephson junction array embedded in a Fabry-Perot resonator are reported in this paper.The mm-wave coherent emission from the series junction array results from the interaction of the junctions with the substrate serving as the dielectric resonator as well as the Fabry-Perot resonator.The central frequency of emission of a Josephson junction array containing 166 bicrystal junctions was 75.84 GHz,and the detected emission power was about 10 pW at 77 K.

We proposed a method for implementing impedance matching and phase locking of Josephson junction arrays based on Hes previous report on the coupling mechanism of a millimeter wave radiation to bicrystal Josephson junction arrays embedded in a Fabry-Perot resonator，and relevant electromagnetic simulations and numerical calculations were performed. A bicrystal Josephson junction array was fabricated on a YSZ bicrystal substrate，and embedded in a Fabry-Perot resonator. Impedance matching was implemented by integrating an optimized half-wavelength dipole array fed in series with the junction array，and numerical calculations showed that the radiation efficiency of a single junction reached 94%. Through making good use of the radiation characteristics of the antenna array and optimizing the model，the FP resonator and the substrate can be driven to resonate in proper modes respectively，which benefits the high frequency electromagnetic coupling between the junction array and the resonators. The numerical simulations proved that this method is effective for realizing self-voltage locking and mutual-phase locking of junction arrays. The method proposed in this paper and calculation results are valuable for guiding the applications of Josephson junction arrays in THz signal generators and voltage standards.

The millimeter wave irradiation characteristics of a Tl-2212 high-temperature superconducting thin film bicrystal Josephson junction embedded in a hemispherical Fabry-Perot resonator was studied. The coupling characteristics of the bicrystal Josephson junction with the Fabry-Perot resonator have been investigated experimently, showing that it was greatly affected by the factors such as the location of the sample in the open resonator, the angle between them, the pattern of the junction and the distance between the two reflecting mirrors of the resonator. The optimized coupling between Josephson junction and applied microwave was achieved by refined adjustment of the factors. In this case, 9 orders distinct Shapiro steps were observed. Taking advantage of the Fabry-Perot resonator technique, the coupling problem between high-temperature superconducting thin film Josephson junction and applied millimeter wave was well solved, which is of significance for the research on radiation and detection of millimeter wave and terahertz wave of high-temperature superconducting Josephson junction.

A linear phase high temperature superconducting （HTS） filter fabricated on LaAlO3 substrates is presented. The designed passband of the HTS filter is 10 MHz and the group delay ripples over 80% of the passband is less than 20 ns. The filter consists of novel resonators, which are able to minimize the spurious couplings between resonators. As a result, the filter shows not only the linear phase characteristic but also the symmetrical frequency response. The measured passband is 9.85 MHz. The return loss is better than 16 dB and the out-of -band rejection is better than 80 dB. The measured group delay ripples is about 20 ns, which is in good agreement with the simulated result.