Prediction of metasurface spectral response based on a deep neural network.

The two-dimensional optical metasurface can realize the free regulation of light waves through the free design of structure, which is highly appreciated by researchers. As there are high requirements for computer hardware, long time for simulation calculations, and data waste in the process of using the time-domain finite-difference method to solve the optical properties of the metasurface, the deep neural network (DNN) is proposed to predict the spectral response of an optical metasurface. The structural parameters of the metasurface are taken as inputs and the metasurface transmission spectrum is used as the output. To achieve better prediction results, different gradient descent algorithms were selected and the parameters of the DNN model were optimized. After 5 × 104 times of epoch training, the loss function mean squared error (MSE) reaches 2.665 × 10-3, the sum error of 98% test data is less than 3.23, and the relative error is less than 2%. The results show that the DNN model has an excellent prediction effect. Compared with the traditional simulation method, the efficiency of this model is improved by 104 times, which can improve the efficiency of optical micro-nano structure design.

Metasurface parameter optimization of Fano resonance based on a BP-PSO algorithm.

An all-dielectric metasurface is proposed, and the transmission spectrum is analyzed by numerical simulation. The Fano resonance line appears in the transmission spectrum. The mechanism of Fano resonance is analyzed based on multipole coupling theory. The mathematical model between structural parameters and spectral performance is established by the back propagation (BP) neural network. Then, the genetic algorithm, sparrow search algorithm, and particle swarm optimization (PSO) algorithms are used to find the structural parameters corresponding to the optimal performance. The result shows that the quality factor is increased by three times, reaching 3805, and the modulation depth is close to 100% after PSO optimization. Our study provides a new method for the design of metasurfaces and parameter optimization of optical micro-nano structures.

Effect of azithromycin in combination with simvastatin in the treatment of chronic obstructive pulmonary disease complicated by pulmonary arterial hypertension.

OBJECTIVE: To evaluate the effect of azithromycin in combination with simvastatin in the treatment of chronic obstructive pulmonary disease (COPD) complicated by pulmonary arterial hypertension. METHODS: Eighty-six patients who developed COPD and pulmonary arterial hypertension and received treatment from August 2013 to October 2014 were selected and randomly divided into an observation group and a control group using random number table, 43 in each group. Patients in the control group were orally administrated 20 mg of simvastatin, once a day. Patients in the observation group took 0.25g of azithromycin enteric-coated tablets, once a day, besides simvastatin. The treatment course of both groups was six months. Blood gas analysis indexes, forced expiratory volume in first second (FEV1), six minutes walking distance, dyspnea grade and blood lipid parameter were recorded and compared between the two groups. RESULTS: Arterial partial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2) of the observation group were (68.13±3.03) mmHg and (45.08±2.27) mmHg after treatment, respectively. In the control group, the values were (60.01±4.72) mmHg and (38.93±1.61) mmHg, respectively. The improvement amplitude of the observation group was superior to that of the control group (P<0.05). FEV1, forced vital capacity (FVC) and 6-minutes walking distance of the observation group were (1.08±0.11) L, (2.1±0.2) L and (380.34 ± 31.28) m respectively after treatment, superior to the control group ((0.93±0.09) L, (1.7±0.1) L) and (302.79±29.74) m, and the difference had statistical significance (P<0.05). The levels of peripheral systolic blood pressure (PSBP) and peripheral diastolic blood pressure (PDBP) of patients in the observation group were both lower than those of the control group, and the difference had statistical significance (P<0.05). CONCLUSION: Azithromycin in combination with simvastatin has definite effect in the treatment of COPD in combination with pulmonary arterial hypertension as it can significantly relieve ventilation disturbance, improve lung function, and decrease pulmonary arterial pressure. Hence it is worth clinical promotion.

Decreased serum 5-oxoproline in TB patients is associated with pathological damage of the lung.

BACKGROUND: Tuberculosis (TB) is a serious world-wide health problem, causing millions of deaths every year. Metabolomics is a relatively new approach to identify disease specific biomarkers. However, there is little information available on metabolite biomarkers in TB. In this study, we used gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS) to identify serum metabolite biomarkers associated with the active state of TB. METHODS: Potential biomarkers were selected by comparing serum metabolites in 10 healthy donors with 10TB patients, and in 6TB patients before and after treatment. Selected biomarkers were then validated using a larger population of samples from 120 healthy donors and 120TB patients derived from different clinical backgrounds RESULTS: The 5-oxoproline level was consistently low in patients with active TB. Further validation in larger population of clinical samples showed that 5-oxoproline was associated with pathological damage of the lung but not with age, sex, or bacterial burden in TB patients. CONCLUSIONS: Serum 5-oxoproline may be a useful biomarker for active TB and pathological damage of the lung.

Flammeovirga pacifica sp. nov., isolated from deep-sea sediment.

Strain WPAGA1T was isolated from marine sediment of the west Pacific Ocean. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belonged to the genus Flammeovirga. Strain WPAGA1T exhibited highest 16S rRNA gene sequence similarity with Flammeovirga yaeyamensis NBRC 100898(T) (98.1 %) and lower sequence similarity with Flammeovirga arenaria IFO 15982T (94.6 %) and other members of the genus Flammeovirga (<94.2 %). DNA-DNA relatedness studies showed that strain WPAGA1T was distinct from F. yaeyamensis NBRC 100898T and F. arenaria NBRC 15982T (43±4 % and 32±2 % relatedness values, respectively). Strain WPAGA1T could be distinguished from all known members of the genus Flammeovirga by a number of phenotypic features. However, the dominant fatty acids of strain WPAGA1T (iso-C15:0, C16:0 and C20:4ω6,9,12,15c), the major polyamine (cadaverine) and the G+C content of the chromosomal DNA (32.9 mol%) were consistent with those of members of the genus Flammeovirga. Based on phenotypic and chemotaxonomic features and 16S rRNA gene sequences, strain WPAGA1T can be assigned to the genus Flammeovirga as a representative of a novel species, for which the name Flammeovirga pacifica sp. nov. is proposed; the type strain is WPAGA1T (=CCTCC AB 2010364T=LMG 26175T=DSM 24597T=MCCC 1A06425T).