Hybrid coupling enhances photoluminescence of monolayer MoS2 on plasmonic nanostructures.

The efficiency of photoluminescence (PL) of transition-metal dichalcogenides (TMDCs) significantly influences their practical applications in optoelectronic devices. In this work, we study multiple coupling among excitons, surface plasmons, and optical modes, and their effects on PL of monolayer MoS2 atop plasmonic nanohole arrays. Under the illumination of visible light, strong intensity enhancement of PL from monolayer MoS2 is observed in the system. We further demonstrate that there exist excitons induced from MoS2, localized and propagating surface plasmons excited from nanoholes, and optical modes related to the incident laser. And hybrid coupling of those modes significantly improves the PL signals and also lightens the PL images of monolayer MoS2. This work provides a unique way to improve the emission of monolayer TMDCs. The atomically thin TMDCs coupled to plasmonic metamaterials are also promising for advanced applications such as ultrathin integrated light-emission diodes, photodetection, and nanolasers.

[Allelopathy of grape root aqueous extracts].

Taking the tissue-cultured seedlings of grape cultivar Red Globe as test objects, this paper examined the effects of their root aqueous extracts on seedling's growth, with the allelochemicals identified by LC-MS. The results showed that 0.02 g x ml(-1) (air-dried root mass in aqueous extracts volume; the same below), 0.1 g x ml(-1), and 0.2 g x ml(-1) of the aqueous extracts inhibited the growth of the seedlings significantly, and the inhibition effect increased with increasing concentration of the extracts. The identified allelochemicals of the extracts included p-hydroxybenzoic acid, salicylic acid, phenylpropionic acid, and coumaric acid. Pot experiment showed that different concentration (0.1, 1, and 10 mmol x L(-1)) salicylic acid and phenylpropionic acid inhibited the seedling' s growth remarkably. With the increasing concentration of the two acids, the plant height, stem diameter, shoot- and root fresh mass, leaf net photosynthetic rate and starch content, and root activity of the seedlings decreased, while the leaf soluble sugar and MDA contents increased. No obvious change pattern was observed in leaf protein content.

[Therapeutic effect of staged surgery for central cord syndrome of the cervical spine].

OBJECTIVE: To evaluate the effect of staged surgical treatment on central cord syndrome of the cervical spine. METHODS: A retrospective analysis was conducted in 36 cases of central cord syndrome of the cervical spine treated with staged surgery. The patients (aged 50 to 79 years, mean 56.9 years) were divided into group A (50 to 64 years old, n=20) and group B (above 65 years old, n=16), and each group was further divided into 2 subgroups according to the range of decompression in the second stage, namely A1, B1 and A2, B2. ASIA motor score (AMS) was analyzed before the first-stage surgery, before the second-stage surgery and at the last follow-up after the second-stage surgery. RESULTS: All the surgeries were performed successfully. The patients were followed up for 12 to 32 months (mean 18.4 months) after the second-stage surgery. After the first-stage surgery, the AMS was 75.8-/+14.6 in group A, 73.2-/+13.1 in group B, 78.5-/+10.2 in group A1, 76.8-/+9.5 in group A2, 72.2-/+12.6 in group B1 and 77.4-/+18.3 in group B2. The AMS at the last follow-up was 90.7-/+10.5 in group A, 89.5-/+12.4 in group B, 91.3-/+13.2 in group A1, 90.7-/+14.8 in group A2, 88.5-/+11.2 in group B1 and 92.4-/+13.6 in group B2. There was no significant difference between groups A and B or between the subgroups A1 and A2 and groups B1 and group B2. The AMS was 75.8-/+14.6 after the first-stage surgery and 90.7-/+10.5 at the last follow-up in group A, significantly higher than those in group B (73.2-/+13.1 and 89.5-/+12.4, respectively, P<0.05). CONCLUSION: Staged surgery is effective for treatment of central cord syndrome of the cervical spine, and the effect of the surgery is not related to the patients' age or the range of decompression.

[Effects of grape-replanting on soil bacterial and fungal populations].

Rhizosphere and non-rhizosphere soil samples were collected from the vineyards having been planted for 3 and 30 years, and PCR-DGGE technique was adopted to study the effects of grape-replanting on the population structure and diversity of soil bacteria and fungi. The bacterial and fungal diversities were higher in 30-year-planted vineyard than in 3-year-planted vineyard, and higher in rhizosphere soil than in non-rhizosphere soil. After 30 years replanting, the population structure of bacteria and fungi approached the same in rhizosphere soil and non-rhizosphere soil but differed from that in fallow soil; while in the 3-year-planted vineyard, the population structure in rhizosphere soil was different from that in non-rhizosphere soil and fallow soil. Comparing with that in 3-year-planted vineyard, the rhizosphere soil microbial population in 30-year-planted vineyard had a greater change. In bacterial population, Flavobacterium sp. (DQ339585) and Bacillus sp. (AY039821) decreased while Pedobacter sp. (AJ871084) increased; in fungal population, Omphalina farinolens (EF413029) appeared, Pestalotiopsis sp. (DQ657877, DQ657875, DQ657871), Phacidium lacerum (DQ470976), and Lecythophora decumbens (AF353597) decreased, while Pilidium acerinum voucher (AY48709) increased. Bacillus sp., Flavobacterium sp. , and Pestalotiopsis sp. had antagonism to pathogen, and their decrease reduced the resistance of grape against pathogen. The increase of Pilidium acerinum voucher might relate to the severe disease after grape-replanting.