Construction of 2D-layered quantum dots/2D-nanosheets heterostructures with compact interfaces for highly efficient photocatalytic hydrogen evolution.

The emergence of two dimensional (2D) nanosheets provides flexible platforms for the construction of semiconductor heterostructures for photocatalytic hydrogen evolution. However, the compact and conformal contact between the components with different dimensions remains challenge. Herein, we anchor the 2D layered black phosphorous quantum dots (BPQDs) onto the 2D ZnIn2S4 nanosheets with sulfur vacancies (V-ZIS). This unique interface between 2D layered QDs and 2D nanosheets ensures a sufficient contact area between the BPQDs and the V-ZIS, which is conducive to the transport and the spatial separation of photogenerated electrons and holes. A synergistic effect of sulfur vacancies and type-Ⅱ heterojunction results in an excellent photocatalytic hydrogen evolution performance of the BPQDs/V-ZIS composites. The hydrogen evolution rate by the BPQDs/V-ZIS without any noble-metal as cocatalyst is up to 5079 µmol g-1h-1 under visible light irradiation with an apparent quantum yield (AQY) of 12.03% at 420 nm, which is dramatically higher than most other photocatalysts reported previously.

Effects of Atrazine on Chernozem Microbial Communities Evaluated by Traditional Detection and Modern Sequencing Technology.

Atrazine is a long residual herbicide commonly used in maize fields. Although atrazine can effectively control weeds and improve crop yield, long-term application leads to continuous pollution in the agricultural ecological environment, especially in the soil ecosystem, and its impact on soil microorganisms is still not clear. Four methods were used in the experiment to clarify the effect of atrazine on the bacterial populations of cultivated soil layers of chernozem in a cold region in different periods: high-performance liquid chromatography (HPLC), colorimetry, microplate, and high-throughput sequencing. The level of residual atrazine in cold chernozem decreased from 4.645 to 0.077 mg/kg soil over time, and the residue gradually leached into deep soil and then decreased after accumulating to a maximum value. Atrazine significantly affected the activities of urease and polyphenol oxidase activity in the soil layers at different periods but had no significant effect on sucrase and phosphatase activity. Atrazine significantly reduced the diversity of microbial carbon source utilization and total activity in soil layers of 0-10 and 20-30 cm but only reduced the diversity of microbial carbon source utilization in the 10-20 cm layer. Atrazine had no significant effect on bacterial populations (10-12 phyla, 29-34 genera), but had a slight effect on the relative abundance of various groups. Atrazine significantly reduced the diversity of bacterial populations in cultivated soil layers of chernozem in a cold region, and the diversity of bacterial populations decreased with decreased residue. This lays a foundation for guiding the safe use of herbicides on farmland in Northeast China.

[Long-term efficacy of nasal endoscopic opticnerve decompression for traumatic optic neuropathy].

OBJECTIVE: To analyze the long-term efficacy of nasal endoscopic opticnerve decompression for traumatic optic neuropathy(TON) and to explore its possible influencing factors. METHOD: To summarize the clinical data of 39 cases underwent transnasal decompression, which were followed-up for more than 1 year. The data, including optic canal CT scanning, flashed-elicited visual-evoked potential (FVEP), preoperational vision and visual field examination were reviewed. Nasal endoscopic optic nerve decompression was preformed. Whether or not optic nerve sheath incision decided to perform was according to preoperative CT and situations in operation. Postoperative follow-up including vision, visual field, funduscopy, nasal endoscopy were performed. RESULT: Total efficacy rate was 30. 77% (12/39), inefficacy rate was 69. 23%(27/39). The efficacy rate was 85. 71% with better than nolight perception, and the efficacy rate was 18. 75% with nolight perception, the clinical effect in the group of preoperative better than nolight perception was better than that of nolight perception, the difference was statistically significant (P<0. 05). The efficacy rate was 34. 38% with duration of less than 7 days from the traumatic point to the operation point, and the efficacy rate was 14. 29% for more than 7 days, but the difference was not statistically significant (P> 0. 05). The efficacy rate was 26. 32% with optic nerve sheathincision, while the efficacy rate was 35. 00% without optic nerve sheath incision, and there was no statistically significant difference (P>0. 05); Postoperative vision tended to stabilize until about 6 months post-operation, without complications. CONCLUSION: The long-term efficacy of nasal endoscopic opticnerve decompression for TON was certain; The efficacy with preoperative residual vision was better than that of nolight perception, the factor of long or short duration from the trauma point to the operation point and the factor of optic nerve sheath incision didn't influence long curative effect. To avoid the secondary damage to the optic nerve after trauma was the key to increase long curative effect in TON.

V-ATPase Is Involved in Silkworm Defense Response against Bombyx mori Nucleopolyhedrovirus.

Silkworms are usually susceptible to the infection of Bombyx mori (B. mori) nucleopolyhedrovirus (BmNPV), which can cause significant economic loss. However, some silkworm strains are identified to be highly resistant to BmNPV. To explore the silkworm genes involved in this resistance in the present study, we performed comparative real-time PCR, ATPase assay, over-expression and sub-cellular localization experiments. We found that when inoculated with BmNPV both the expression and activity of V-ATPase were significantly up-regulated in the midgut column cells (not the goblet cells) of BmNPV-resistant strains (NB and BC8), the main sites for the first step of BmNPV invasion, but not in those of a BmNPV-susceptible strain 306. Furthermore, this up-regulation mainly took place during the first 24 hours post inoculation (hpi), the essential period required for establishment of virus infection, and then was down-regulated to normal levels. Amazingly, transient over-expression of V-ATPase c subunit in BmNPV-infected silkworm cells could significantly inhibit BmNPV proliferation. To our knowledge this is the first report demonstrating clearly that V-ATPase is indeed involved in the defense response against BmNPV. Our data further suggests that prompt and potent regulation of V-ATPase may be essential for execution of this response, which may enable fast acidification of endosomes and/or lysosomes to render them competent for degradation of invading viruses.

[Study of sonochemical degradation of microcystins].

Sonochemical degradation of microcystins (MC) produced by microcystis in water and the influence of various ultrasonic parameters were studied. The results show that microcystins could be effectively degraded in ultrasonic fields. 150 kHz is the best ultrasound frequency for microcystins degradation, and the removal ratio of microcystins reached 70% after 20 min ultrasonic irradiation at 150 kHz and 40 W. Furthermore, ultraviolet irradiation strengthened the ultrasonic degradation of microcystins.