A plasmon modulator by directly controlling the couple of photon and electron.

The manipulation of surface plasmon polaritons plays a pivotal role in plasmonic science and technology, however, the modulation efficiency of the traditional method suffers from the weak light-matter interaction. Herein, we propose a new method to overcome this obstacle by directly controlling the couple of photon and electron. In this paper, a hybrid graphene-dielectric- interdigital electrode structure is numerically and experimentally investigated. The plasmon is excited due to the confined carrier which is regulated by the potential wells. The frequency of plasmon can be tuned over a range of ~ 33 cm-1, and the obtained maximum extinction ratio is 8% via changing the confined area and the density of carrier. These findings may open up a new path to design the high efficiency all-optical modulator because the electrons can also be driven optically.

Nano-particle transport and the prediction of a valid area to be trapped based on a plasmonic antenna array.

Optical antennas are promising for optical trapping and particle manipulation, when converting light between localized energy and freely propagating radiation. In this paper, we proposed a numerical method for the transport of nanoparticles using the optical force field over a plasmonic Au antenna array. The plasmonic Au antenna array is designed to produce strong near-field hot spots when illuminated by a plane wave. The hot spots function as optical traps, separately addressable by their resonant wavelengths. By changing the traps sequentially, the nanoparticles can be handed off between adjacent traps. We also demonstrated a valid area in which the nanoparticles could be trapped and transferred stably by discussing the trapping potential that particles encountered. The simulated and calculated results showed that this method had promising applications in the field of biochemical diagnoses and high-accuracy optical manipulation.

A high-precision, template-assisted, anisotropic wet etching method for fabricating perovskite microstructure arrays.

Cesium lead-halide (CsPbX3; X = Cl, Br, I) perovskite microstructure arrays have become the basis for laser array applications, due to their outstanding spectral coherence, low threshold, and wideband tunability. Furthermore, the common fabrication methods for these arrays have the limitation to achieve both tailored design and high resolution simultaneously. Herein, we report a high-precision, template-assisted, wet etching (TAWE) method for the preparation of perovskite microstructure arrays. This method possesses the advantages of flexible design, controllable size, and ultrahigh accuracy (the resolution can reach 1 µm or higher). A 20 × 20 inverted pyramid array with a diameter of 3 µm and a period of 4 µm was fabricated using this method. CsPbBr3 perovskite quantum dots fabricated by means of hot injection were filled into the inverted pyramid array via spin-coating and pumped using a laser with a wavelength of 400 nm. The lasing characteristics of the array were then measured and analyzed; the threshold was measured to be 37.6 µJ cm-2, and the full width at half maximum of the amplified spontaneous emission spectrum was found to be about 4.7 nm. These results demonstrate that perovskite microstructure arrays prepared via this method have potential applications in laser arrays.

A simple multiple centrifugation method for large-area homogeneous perovskite CsPbBr3 films with optical lasing.

Large scale cesium lead-halide (CsPbX3, X = Cl, Br, and I) perovskite films have become the basis of laser applications. Common fabrication methods such as spin-coating and thermal evaporation have a trade-off between high quality and low cost. Herein, we reported a facile method for preparing a large area homogeneous perovskite CsPbBr3 film via a multiple centrifugal deposition and solvent annealing (MCDSA) method. This method is superior because it can control the thickness (180 nm to 880 nm) of the film, ensure the film is crack and pinhole free, has a large area (2.5 cm × 2.5 cm), and has a low surface roughness (a root mean square of 32 nm). Multiple times of centrifugation and solvent annealing in the MCDSA method are key to improving the quality of the film as well as the laser performance. With increased centrifugation cycles from one to four, the thickness of the film increases from 180 nm to 880 nm, leading to a decrease in the laser threshold from 18.1 µJ cm-2 to 14.2 µJ cm-2 and an increase in the gain coefficient from 78.5 cm-1 to 112.7 cm-1. When solvent annealing is employed, the gain coefficient is further increased to 122.7 cm-1.

[Comparative Analysis of Different Soil Amendment Treatments on Rice Heavy Metal Accumulation and Yield Effect in Pb and Cd Contaminated Farmland].

Using selected sepiolite (SEP) and biochar (BC) as contrasts, we investigated the effects of a new cross-linked modified chitin (CC) on the bioavailability of Pb and Cd in soils, the yield of rice, and the absorption and accumulation of Pb and Cd in different parts of rice plants in a field environment. We hope this study provides the basis for the application of this material to improve soil fertility, and a direction for further soil improvement studies. A field experiment was carried out in 2015-2016 on selected Pb- and Cd-contaminated rice fields in Linghai, Liaoning. The changes in soil pH and available Pb and Cd in the soil were analyzed after the rice was harvested(October 2016). The effects of different treatments on the growth traits and yield of rice, the absorption of Pb and Cd by rice roots, stems and leaves, and grains were compared. The results showed that adding 167-333 kg·hm-2 CC could increase the soil pH value by 0.36-0.45 units, decreasing the contents of available Pb and Cd in the soil by 46.39%-64.01% and 29.73%-43.24% respectively (P<0.05). This treatment significantly reduced the Pb and Cd contents in all parts of rice (P<0.05) compared to conventional fertilization; Pb and Cd contents in different parts of rice were significantly reduced (P<0.05) by 16.09%-38.14% and 21.22%-31.38% in the root, 19.17%-46.92% and 25.66%-45.34% in the stem and leaf, and 29.47%-58.25% and 44.75%-64.02% in the grain, respectively. The treatment of adding 333 kg·hm-2 CC (CC-2) reduced the contents of Pb and Cd in rice grains to 0.2041±0.011 mg·kg-1 and 0.1922±0.021 mg·kg-1, respectively, which were lower than or close to the limit values of Pb and Cd in rice (0.20 mg·kg-1) as per GB 2762-2005. Compared to conventional fertilization, SEP treatment, and BC treatment, without adding any amendments, the yield per mu of rice under CC treatment increased by 33.6-47, 27.6-44, and 8.67-34.77 kg, respectively. The effect of CC-2 treatment on yield was the most obvious; the yield of rice per mu increased by 47 kg, and the yield increase rate was 8.59%. The ability of CC to repair soil contaminated by Pb and Cd and to reduce the contents of Pb and Cd in rice was not weaker than that of SEP and BC. The CC treatment also controlled the migration and redistribution of Pb and Cd in soil-rice systems, and significantly increased the yield of rice. It has good potential to ensure the safe production of rice.

[Sn-glycerol-3-phosphate acyltransferases (GPATs) in plants].

Sn-glycerol-3-phosphate acyltransferase (GPAT) catalyzes the acylation at sn-1 position of glycerol-3-phosphate to produce lysophosphatidic acid (LPA) in an acyl-CoA or acyl-ACP-dependent manner, which is the initial and rate-determining step of TAG biosynthetic pathway. Some GPATs have sn-2 transfer activity. Part members of the GPAT gene family have been cloned from different plant species. Based on their subcellular localizations, GPATs can be classified into three types, plastid GPATs, mitochondria GPATs and endoplasmic reticulum GPATs. GPATs exhibit diverse biochemical properties and are involved in synthesis of several lipids such as TAG, suberin, and cutin which play important roles in the growth and development of plants. This review summarized the current understanding of the chromosomal locus and gene structure of GPAT genes and the subcellular localization, sn-2 regiospecificity, substrates specialty, and functions of GPATs in plants.

[Expression of HCV NS5A gene in HepG2 cell and the effect of the NS5A expression on PI3K in vitro].

AIM: To reveal the influence of HCV-NS5A on PI3K, we probe into the relationship between NS5A and PI3K in vitro. METHODS: Full length NS5A gene of HCV was amplified by PCR, using the plasmid containing HCV full-length open reading frame (ORF) as template, and cloned into the eukaryotic expressing plasmid pcDNA3.0(-) by DNA recombination technique. The recombinant vector was identified by digestion with restriction enzymes and polymerase chain reaction and by directly sequencing. Then both the recombinant vector pcDNA3.0(-)-NS5A and the control vector pcDNA3.0(-) were transfected HepG2 cell using Lipofectamin2000. RESULTS: Expressing NS5A was proven by RT-PCR and Western blot analysis in transfected HepG2 cell. Further more we examined the PI3K protein expressed in the HepG2 cell expressing recombinant NS5A. CONCLUSION: NS5A can activate PI3K in vitro and its signal cascade pathway.

[The research on monoamine neurotransmitters changes in plasma and cerebrospinal fluid in patients with persistent vegetative state].

AIM: To study the relationships between the pathogenesis of persistent vegetative state (PVS) and the levels of monoamine neurotransmitters in plasmas and cerebrospinal fluids (CSFs) in patients with PVS. METHODS: The high-pressure liquid chromatography (HPLC) was used to detect. RESULTS: It was found that the level of dopamine (1.95 +/- 0.99) was significantly increased in plasma compared with the control (1.16 +/- 0.47) (P < 0.05), but the levels of 5-HT, TYR, TRP, GABA of plasma were insignificantly changed. In cerebrospinal fluid, the level of DA was insignificantly changed, and the level of 5-HT (0.49 +/- 0.32) was significantly decreased compared with the control (1.02 +/- 0.35) (P < 0.05), but the levels of TYR (1.36 +/- 0.11), TRP (0.63 +/- 0.40), GABA (1.15 +/- 0.61) were significantly increased respectively compared with the controls (0.40 +/- 0.24; 0.29 +/- 0.22; 0.37 +/- 0.45) (P < 0.05; P < 0.05; P < 0.01). The levels of GABA and DA in plasma were significant correlated (P < 0.05), and GABA and DA in CSF were also significant correlated (P < 0.01). CONCLUSION: The results of this study suggested that PVS is related to the decrease of 5-HT in CSF and the increase of DA in plasma.

[Association between apolipoprotein E gene polymorphism and the patients with persistent vegetative state in the Chinese].

We studied the relationship between apolipoprotein E gene polymorphism and persistent vegetative state (PVS) to explore the genetics background of PVS, and evaluated the effect of ApoE gene polymorphism on lipid levels in plasma. The ApoE genotype of fifty-six patients with PVS and fifty-three controls were determined by PCR and restriction fragment length polymorphism (PCR-RFLP). Plasma lipid levels were measured by using routine methods. Results demonstrated that there were five genotypes in the two groups: E3/3, E3/4, E2/2, E2/3 and E2/4. The genotype frequencies of ApoE gene in PVS were 21(37.5%), 26(46.4%), 2 (3.6%), 5(8.9%), 2(3.6%) and that in control were 37(69.8%), 7(13.2%), 2(3.8%) 5(9.4%), 2(3.8%) respectively. We compared the genotype frequencies between the two groups and found there was a significantly increase in E3/4(chi 2 = 14.236, P < 0.001) and decrease in E3/3(chi 2 = 5.348, P < 0.05). epsilon 2, epsilon 3 and epsilon 4 allele frequencies of ApoE were 11(9.8%), 73(65.2%), 28(25%) in PVS and were 11 (10.4%), 86(81.1%), 9(8.5%) in control respectively. Allele frequencies, significantly increased in epsilon 4 (chi 2 = 10.533, P < 0.001) and decreased in epsilon 3 (chi 2 = 7.022, P < 0.01). We also found that E3/4, E2/4 genotype and epsilon 4 allele can largely increase total cholesterol (TC) and lower density lipoprotein cholesterol (LDL-C) levels in plasma, and epsilon 2 alleles also can largely increase LDL-C levels inplasma. Our finding indicates that the ApoE gene polymorphism may be in association with the PVS, and may be a factor in the genetic susceptibility to PVS in Chinese; Genotype and alleles of ApoE in PVS can affect the lipid levels in plasma.