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Surface plasmon coupled emission (SPCE) is a new analytical technique that provides increased and directional radiation based on the near-field interaction between fluorophores and surface plasmons but suffers from the limitation of insufficient sensitivity. The assembly of hollow-porous plasmonic nanoparticles could be the qualified candidate. After the introduction of gold nanocages (AuNCs), fluorescence signal enhancement was realized by factors over 150 and 600 compared with the normal SPCE and free space emission, respectively, with a fluorophore layer thickness of approximately 10 nm; hence, the unique enhancement of SPCE by the AuNCs effectively overcomes the signal quenching induced by resonance energy transfer (in normal SPCE). This enhancement was proven to be triggered by the superior wavelength match, the enhanced electromagnetic field, and new radiation channel and process induced by the AuNC assembly, which provides an opportunity to increase the detection sensitivity and establish an optimal plasmonic enhancement system. The amplified SPCE system was employed for multiwavelength simultaneous enhancement detection through the assembly of mixed hollow nanoparticles (AuNCs and gold nanoshells), which could broaden the application of SPCE in simultaneous sensing and imaging for multianalytes.

To clarify the influence of the changes in the overlying water environment on the internal nitrogen release from reservoir sediments in different seasons, the quantitative linear relationship between the intensity of the nitrogen release from the sediment and the environmental factors of the overlying water was established, and their contribution rate to the nitrogen pollution of the reservoir during different storage periods was investigated. In this study, the sediment samples were collected from the Dahekou Reservoir in the Xilingol League, and the orthogonal simulation experiments were conducted in the laboratory. The mathematical model, which was established using multiple linear regression methods, revealed the following. The order of the significance of the influences of the environmental factors on the nitrogen release from the sediments in the Dahekou Reservoir is water temperature (T) > dissolved oxygen (DO) > pH value > hydrodynamic force (K). The total nitrogen release flux from the sediments in the Dahekou Reservoir was 14.278 t/a in 2018, accounting for 27.91% of the total nitrogen (TN) pollution load input during the same period. In particular, in winter, the contribution rate of the nitrogen released from the sediments reached the highest level (57.06–63.26%), which was significantly higher than the river’s contribution to the total nitrogen pollution load of the reservoir. The nitrogen released from the sediments became the main source of nitrogen nutrients in the reservoir in the ice-sealed period.

Deposition is the main migration process of low-density microplastic aggregation in lakes. In order to explore the deposition law of low-density microplastic aggregation in Wuliangsu Lake, a microplastic trap was designed and applied to examine the deposition process based on the similarities and differences between microplastics and naturally occurring suspended solids. The deposition processes of different sizes and shapes of low-density microplastic aggregation were quantified in Wuliangsu Lake. The results showed that the deposition fluxes of all types of low-density microplastic aggregation increased with wind speed. The deposition of flux of low-density microplastic aggregations with a similar shape of fiber and with a size ranging from 0.05-0.5, 0.5-2, and 2-5 mm had better correlation with wind speed. The correlation coefficient changed from 0.218 to 0.836. The deposition of flux of low-density microplastic aggregations with a similar shape of fiber, fragment, grain, and film and with size ranging from 0.05-0.5, 0.5-2, and 2-5 mm under different wind speeds at different experiment sites changed from 0-(1458±284), 0-(368±144), 0-(71±37), and 0-(85±65)n·(m

Concern has been expressed regarding the impacts of climate change on river ice and ice jam formation in cold regions. Ice jams are easily initiated in bends and narrow channels and cause disasters. In this study, observations and remote sensing monitoring are used to study the freeze-up ice jam formation of bends. Sediment transport and freezing process of the river interact, influencing bed changes profile and sedimentary budget. River ice processes, channel evolution, ice hydro-thermodynamics, and ice jam accumulation are explored. The results show that the channel topography determines the river thalweg, and that the channel elevation interacts with the river ice through sediment transport. The channel shrinkage increases the probability of ice jam, and the sharp bend is prone to ice jam formation. Under the effect of secondary circulation flow in the bend and in the outer bank, the juxtaposed freeze-up and the hummocky ice cover occur in the same location, and frazil ice accumulates under the junction of the main channel and the shoals. Affected by the increase of the hydraulic slope and the velocity downstream, open water reaches develops downstream of the ice accumulation. An open water section is emerged upstream of the bend, due to the ice deposition, and partly cut-off supply of the frazil.

Hepatitis B Virus (HBV) infection in infancy or early childhood leads to high rate of persistent infection (25-90%). The immunological basis of high rate of viral persistence in vertically acquired HBV infections is not completely understood. Dendritic cells (DCs) are one of the most potent antigen-presenting cells (APC) and play pivotal roles in the enhancement or regulation of antiviral immune reactions. Aim of the present study was to investigate whether an HBV-infected maternal environment might influence the infants’ DC phenotype and function. Monocyte-derived DC (MoDC) of neonates born to HBsAg-positive mothers were studied phenotypically by Flow Cytometry (FCM) and functionally by mixed lymphocyte reaction (MLR) and enzyme-linked immunosorbent assay (ELISA). An electron microscope was used to analyze the morphological changes of MoDC. MoDC from neonates whose maternal HBV DNA was>5×107 copies/ml showed a reduced surface expression of CD80, CD86, and HLA-DR as compared to that in neonates whose maternal HBV DNA was negative (CD80: t=3.238, P=0.002; CD86: t=3.543, P=0.001; HLA-DR: t=2.785, P=0.008). T-cell proliferation assays also showed an impaired allostimulatory capacity in comparison to that in neonates whose maternal HBV DNA was negative, especially in the cultures at a DC: T cell ratios of 1:5 and 1:10 (t=-5.442, P

To explore the relationship between the variations of the physiochemical properties of traditional Chinese medicine(TCM) decoction before or after precipitation in alcohol and the wall stickiness in spray drying. In this study, widely used TCMs in clinic were selected to determine the physiochemical properties of TCM decoction before or after precipitation in alcohol separately.Afterwards, the principle component analysis(PCA),Hierarchical cluster analysis(HCA),and orthogonal partial least squares-discriminate analysis(OPLS-DA) were used to evaluate the relationship between the variations of those liquid before or after precipitation in alcohol and hot-melt stickiness in spray drying.Three types of statistical analysis methods all indicated that ethanol precipitation affected physiochemical properties of TCM decoction, and the variations of physical properties showed significant association with hot-melt stickiness in spray drying.The results of PCA-X and HCA suggested that the dynamic surface tension(DST) was impacted most by the alcohol deposition treatment,at the same time,the other 5 physiochemical properties were also affected.OPLS-DA verified that PCA-X and HCA results, and revealed that DST,equilibrium surface tension(EST) and pH were significantly affected by alcohol deposition treatment,and the order of the affecting factors from high to low was DST,EST and pH.Therefore,the downward trend of DST and pH were the important factors that directly affected the hot-melt stickiness of TCM after precipitation in alcohol,which would be probably caused by losing macromolecules alcoholic insoluble components and increasing relative proportions of organic acid and small molecule sugar.

Recurrent oral ulcer (ROU) is a common disease, and seriously affects the quality of life. There are obvious advantages in improving clinical symptoms, maturity of regenerated mucosa and healing quality, and reducing recurrence rate of ROU. But there is a lack of sufficient experimental data. Tongue diagnosis is an important basis for disease differentiation, syndrome differentiation and treatment, and clinical efficacy monitoring. Tongue coating can reflect the local and global pathological state. The back of the tongue forms a relatively complete and independent microecosystem. The change of tongue body may be a colony indicator for ROU. The pathogenicity of colonized bacteria in ROU may be used as a potential diagnostic marker. Based on microecology, the author reviews the pathogenesis of ROU and the correlation between microecology and both the therapeutic effect and mechanism of ROU in traditional Chinese medicine. DOI: 10.11855/j.issn.0577-7402.2018.09.15

A series of dinuclear lanthanide(III) compounds, namely, [Ln2(tmhd)2L2(CH3OH)2] (Ln(III) = Sm (1), Eu (2), Dy (3) and Er (4); H2L = 2-amino-benzoic acid (8-hydroxy-quinolin-2-ylmethylene)-hydrazide, Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione), have been synthesized, structurally and magnetically characterized. The X-ray structural analysis exhibit that 1–4 are phenoxo-O-bridged dinuclear compounds and central Ln(III) ions are eight-coordinated with one bidentate tmhd−, one CH3OH and two μ2-O bridging Schiff base ligands. Magnetic measurements indicated that slow magnetic relaxation behaviors were observed in 3, with energy barrier (ΔE/kB) of 13.14 K and τ0 = 4.58 × 10−6 s, however, no out-of-phase (χ″) alternating current (ac) signals noticed in 1, 2 and 4. Additionally, solid-state luminescence properties reveal that 1–3 display the characteristic LnIII luminescence at room temperature.

It was recently demonstrated that the density of states (DOS) is the key factor to determine charge transport, photoelectric and contact properties in disordered organic semiconductors. However, the density of states in organic semiconductors is unclear at present. Although the Gaussian DOS is the most popular, some works support the exponential DOS or combination of both forms. In this paper, we propose three exponential-type DOS, one has complete exponential tail, and other two cuts tails at some places. The variations of mobility with carrier density are obtained through numerically solving variable range hopping (VRH) equations. It is shown that the relationships of mobility with density and Fermi level are very different among results obtained from Gaussian, un-cutting and cutting exponential-type DOS. The results show that the experimental mobility-density data can be well fitted by using single cutting exponential-type DOS in the wide ranges of density, but cannot be fitted by using single Gaussian and un-cutting exponential-type DOS. Instead of the Gaussian and pure exponential DOS, the DOS with exponential core and clearly cutting tail is recommended.

Two new Ln2 compounds, namely [Ln2(L)2(CH3OH)2] (Ln = Gd (1) and Dy (2)), have been successfully synthesized and further characterized by crystallography. Structural analysis shows that both 1 and 2 are binuclear compounds, and each LnIII ion is eight-coordinated model and the coordination polyhedron of centre LnIII ion can be represented as a distorted dodecahedron with triangular faces. The magnetic studies reveal that weak antiferromagnetic exchange is existed between the two neighbouring Gd(III) ions in 1. Furthermore, for 1, it exhibits magnetic refrigeration property (magnetic entropy changes −ΔSm = 24.75 J kg−1 K−1 for magnetic field intensity ΔH = 7.0 T at 3.0 K); while for 2, it displays slow magnetic relaxation behavior under zero dc field. When under an external dc field (dc = 3000 Oe), remarkable single-molecule-magnet (SMM) behavior was observed in 2 with the anisotropic barrier (ΔE/kB) of 16.65 K and pre-exponential factor (τ0) of 3.12 × 10−6 s.

To investigate the relationship between maternal peripheral blood mononuclear cells (PBMC) hepatitis B virus (HBV) covalenty closed circular deoxyribonucleic acid (cccDNA) and other HBV serological markers and its effects on HBV intrauterine transmission.We enrolled 290 newborns and their hepatitis B surface antigen (HBsAg) positive mothers. HBV cccDNA in PBMC and HBV DNA in serum were detected by a real-time PCR-TaqMan probe while HBV serological markers were detected with an electrochemiluminescence immunoassay.There was a positive correlation between the levels of PBMC HBV cccDNA and serum HBV DNA and HBeAg (r = 0.436 and 0.403, P0.001). The detection rate of pattern A ['HBsAg (+), HBeAg (+), and anti-HBc (+)'] was significantly higher in the PBMC HBV cccDNA positive group than in the control group (χ2 = 48.48, P0.001). There was a significant association between HBV intrauterine transmission and PBMC HBV cccDNA (χ2 = 9.28, P = 0.002). In the presence of serum HBV DNA, HBeAg, and PBMC HBV cccDNA, the risk of HBV intrauterine transmission was three times higher (OR = 3.69, 95% CI: 1.30-10.42) than that observed in their absence. The risk of HBV intrauterine transmission was the greatest (OR = 5.89, 95% CI: 2.35-14.72) when both PBMC HBV cccDNA and pattern A were present. A Bayesian network model showed that maternal PBMC HBV cccDNA was directly related to HBV intrauterine transmission.PBMC HBV cccDNA may be a direct risk factor for HBV intrauterine transmission. Our study suggests that serological markers could be combined with PBMC-related markers in prenatal testing.

A new device was designed to measure adhesive force and predict whether traditional Chinese medicine extracts would appear hot-melt sticking in spray drying process．Based on the physical property tester as fundamental test platform, the device was fixed with a camera, a temperature and humidity sensor probe and a set of equipment for hot air. This device could simulate the dry environment of spray dryer and analyze the variables of testing solutions' adhesiveness against drying time. To establish and validate a model of predicting hot-melt sticking in spray drying, data was collected by using data mining. The results of this study proved that the device could be used to predict the hot-melt sticking in spray drying based on the adhesive force of materials (testing solutions). In addition, the study also found that the adhesiveness of the hot-melt sticking materials gradually increased with the evaporation of water, while that of non-sticking materials first increased and then rapidly decreased.

To explore the correlation between chemical compositions (organic acids, small molecule sugars, protein and others) of traditional Chinese medicine extracts and the wall stickiness in spray drying. In this study, 55 types of most common used Chinese herbs were selected to determine the content of 7 chemical components such as citric acid and fructose from plant extraction. The status of wall stickiness was observed during the drying process. The principle component analysis (PCA-X), hierarchical clustering analysis(HCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were then used to evaluate the correlation between each chemical compositions and wall stickiness, so as to look for the essential chemical compositions associated with the wall stickiness. All of the above 3 statistical analysis methods showed significant results in distinguishing the two groups (sticky or non-sticky). PCA-X score chart and HCA clustering scatter plot suggested that the small molecular substance was the main factor causing wall stickiness, which was then proved by the reality where some of the traditional herb extracts were in non-sticky state after drying but in sticky state after alcohol precipitation. OPLS-DA results revealed that L-malic acid, citric acid, fructose and glucose were the difference factors for the wall stickiness of the extracts. Under small molecular components, L-malic acid, citric acid, fructose and glucose were the crucial factors that directly led to the hot melt sticky wall of the herbal extracts, and macromolecular substances might ameliorate the function of wall stickiness.

We investigate a percolation process where an additional parameter q is used to interpolate between the classical Erdös–Rényi (ER) network model and the smallest cluster (SC) model. This model becomes the ER network at q = 1, which is characterized by a robust second order phase transition. When q = 0, this model recovers to the SC model which exhibits a first order phase transition. To study how the percolation phase transition changes from second order to first order with the decrease of the value of q from 1 to 0, the numerical simulations study the final vanishing moment of the each existing cluster except the N-cluster in the percolation process. For the continuous phase transition, it is shown that the tail of the graph of the final vanishing moment has the characteristic of the convexity. While for the discontinuous phase transition, the graph of the final vanishing moment possesses the characteristic of the concavity. Just before the critical point, it is found that the ratio between the maximum of the sequential vanishing clusters sizes and the network size N can be used to decide the phase transition type. We show that when the ratio is larger than or equal to zero in the thermodynamic limit, the percolation phase transition is first or second order respectively. For our model, the numerical simulations indicate that there exists a tricritical point qc which is estimated to be between 0.2 < qc < 0.25 separating the two phase transition types.

A spinel-structured LiNi0.5-xCr2xMn1.5-xO4(x=0, 0.05) were prepared via co-precipitation routes. The experiment results from XRD, SEM and electrochemical analyses show that the substitutions of Ni and Cr for Mn in LiMn2O4can not prevent Mn2+from being oxidized into Mn3+in solution process, however,Mn2+oxidation does not change their final crystal structures of spinel phase, but do influence the Li/Ni2+cation mixing and Mn3+occurrence in lattice. After substitution the first charge and discharge capacities decrease but its cycleability is improved significantly, especially for the Ni and Cr co-substitution

In order to protect C/C composites from oxidation, SiC-MoSi 2 composite coating was synthesized by chemical vapor infiltration /reaction (CVI/CVR) technology. A porous Mo layer was prefabricated on SiC coated C/C composites, and then MoSi 2 and SiC were subsequently prepared in a CVI /CVR process using methyltrichlorosilane (MTS) as precursor. The deposition and reaction mechanism of the MoSi 2 -SiC composite coating was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The oxidation behavior of SiC-MoSi 2 coated specimens was tested. The results show that the porous Mo layer can be densified with SiC phase decomposed from MTS, and transformed into SiC-MoSi 2 by reacting with MTS as well. A dense composite coating was prepared with optimized deposition parameters. The coated specimen exhibits a good oxidation resistance with a little mass loss of 1.25% after oxidation at 1500 °C for 80 h.

In order to further study the cracks initiation and distribution mechanism of SiC coating, then optimize the coating structure and composition on surface of C/C composites, CVD method is used to deposit SiC coating on C/C composites and pyrolytic carbon. Through the analysis on the reasons of cracks initiation via SEM, the influence of different kinds of substrates and the toughening of SiC whisker on the cracks initiation and distribution are researched. The results show that the cracks easily form in the area near the defects and sample edge, and the cracks also mainly distribute in the direction which are perpendicular to the first fiber layer. Compared with pyrolytic carbon matrix, cracks on C/C composites matrix are width and numerous, and SiC whisker toughening coating can significantly reduce the number of cracks.

This paper establishes a method to assess thread from air defenses to air attack virtual target. A novel decision-making system is presented for suppression of air defenses by virtual target, which seeks the maximal integrative operational effectiveness. On the basis of characteristics of multiple attribute decision, the model of thread assessment is established. The target choice and the attack sequence at the suppression of air defenses are got by using the model. Then, a new evaluation model to measure the integrative operational effectiveness is developed by introducing the concept of availability matrix, dependability matrix and capability matrix. These matrices are decided by three factors of virtual target: maneuverability, fire attack, electronic jamming. The method is tested and the relevant simulation results show its efficiency.

Space morphology of Dong villages in northern Guangxi has accumulated a rich history and culture, and there exists a unique style in terms of settlement patterns, spatial structure, geomantic pattern and other aspects. Through the description for space morphology of villages, we will analyze the impact of modern civilization on traditional culture of Dong and its causes, and put forward the concept to promoting cultural heritage of villages through cultural reconstruction, idea renewal, resource management and other measures.

We discussed the syntheses table of the standard amino acid based on the graph theory that transformed the syntheses table into a network graph and using the connected-graph concept to discuss the performance of the table based on the various classification results. Finally, we selected a set with 29 specific representative classifications of twenty amino acids to calculate each connected-rate and on average connected-rate of 29 specific reached to 0.944. It means the similar amino acid have been arranged together and get a suitable position in the table, meanwhile the performance of this table reached our required

It is well known that there are some similarities among various naturally occurring amino acids. The standard amino acids have been grouped by their general properties and the chemical structures of their side chains. In this paper we divided the molecular weight of amino acid into two parts: backbone molecular weight Mband side chain molecular weight Ms. We naturally grouped the amino acids into two sets according to the rate of Ms/ Mb. We developed a method to construct a syntheses table to reflect the relevant physicochemical properties based on the PAM250 matrix and successfully established an elegant table of the twenty amino acids. Our work proved that PAM250 matrix could be used not only in finding reasonable alignments but also in grouping similar amino acid.

The analysis of the codon usage pattern of Porcine Cytomegalovirus (PCMV) DPOL gene has both theoretical and practical value in understanding the basics of molecular biology and selecting appropriate expression systems to improve the expression level. In this study, the codon usage pattern of PCMV DPOL gene and other 36 reference herperviruses were analyzed, the results showed that the codon of PCMV DPOL gene was strong bias toward the synonymous codons with G or C at the third codon position, and was closer relatively to these viruses which were classified in Betaherpesvirinae. Correlation analysis indicated that there was no obvious correlation between PCMV DPOL gene and it’s host swine, and 13 codons showed distinct usage preference between PCMV DPOL gene and H.sapiens, whereas 16 in the E.coli and 27 in the yeast. Thus the mammal expression system may be more appropriate for the expression of PCMV DPOL gene.