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Recently, graphene oxide (GO) based materials have shown great potential in the treatment of implant bacterial infections due to its inherent antibacterial activity. However, the effect of GO-based materials on biological systems particularly the antibacterial mechanisms is still not clear. In this study, GO, NaBH4 treated GO (GO-Y), copper decorated GO (GO-Cu, GO-Cu-GO) composited coatings were prepared on the surface of silicon dioxide (SiO2) substrate by spin-coating and chemical in-situ formation. The growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) on GO-Y, GO-Cu, and GO-Cu-GO were significantly inhibited, especially on GO-Cu and GO-Cu-GO coatings. The implied antibacterial mechanism of GO-Cu-Cu coatings was further studied and discussed. The enhanced antibacterial performance of GO-Cu-GO coatings has significant potential application in preventing clinical implant bacterial infections. Moreover, the systematic study of various antibacterial effects also enriches our knowledge of the possible antibacterial mechanisms of graphene-based materials. [ABSTRACT FROM AUTHOR]

Heading date (HD) and flowering date (FD) are critical for yield potential and stability, so understanding their genetic foundation is of great significance in wheat breeding. Three related recombinant inbred line populations with a common female parent were developed to identify quantitative trait loci (QTL) for HD and FD in four environments. In total, 25 putative additive QTL and 20 pairwise epistatic effect QTL were detected in four environments. The additive QTL were distributed across 17 wheat chromosomes. Of these, QHd-1A , QHd-1D , QHd-2B , QHd-3B , QHd-4A , QHd-4B and QHd-6D were major and stable QTL for HD. QFd-1A , QFd-2B , QFd-4A and QFd-4B were major and stable QTL for FD. In addition, an epistatic interaction test showed that epistasis played important roles in controlling wheat HD and FD. Genetic relationships between HD/FD and five yield-related traits (YRTs) were characterized and ten QTL clusters (C1–C10) simultaneously controlling YRTs and HD/FD were identified. The present work laid a genetic foundation for improving yield potential in wheat molecular breeding programmes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We studied the mechanisms of protective effects of propofol on ketamine-induced damage to neonatal cognitive function. MATERIALS AND METHODS: We utilized a rat model of ketamine anaesthesia. Eighty neonatal rats (7 days after birth) were divided into four groups: normal saline group, ketamine group, and low- and high-dose propofol combined with ketamine groups. Six hours after anaesthesia, we obtained hippocampal tissue, and quantified apoptotic index and total protein concentration, and assessed global proteomics changes induced by two tested drugs. The latter changes were documented by two-dimensional electrophoresis and matrix-assisted laser desorption/ ionization time of flight mass spectrometry. To evaluate cognitive functions, water maze test was applied after animals grew for 21 days. We further repeated proteomics studies at 21 days post-anaesthesia. RESULTS: Ketamine markedly up-regulated apoptotic index and decreased total protein concentration. Propofol dose-dependently reverted these adverse changes. Six hours postanaesthesia, combined propofol and ketamine administration up-regulated the following proteins in the hippocampus: PD1A3, NDUFB10, HSPA8, ATP5JD, and PSMA1. Furthermore, the following proteins were down-regulated: PPIA, PKM2, GFAP, NSE, PPIA, PKM2, and GFAP. After 21 days, animals treated with ketamine showed marked disturbances in cognitive function as demonstrated by increased time of the water maze test, whereas propofol diminished these changes. In addition, expression of proteins largely normalized in propofol-treated animals, with only two up-regulated proteins (FUBP3 and PRDX5) and three down-regulated proteins (GAPDH, AKR1A1, and VCP). CONCLUSIONS: Adverse effects of ketamine on cognitive function are reverted by propofol, also through beneficial effects on protein expression in the hippocampus. [ABSTRACT FROM AUTHOR]

The traditional thermal expansion method using a dilatometer fails to accurately determine the original firing temperatures of low-fired ancient pottery. For this reason, we have developed an improved method of determining firing temperatures for low-fired pottery. This paper explains the theory of the improved method and presents the reasonably satisfactory results obtained on ancient pottery from the Donghulin site ( c. 10 000 bp). The method and the results are very important for the study of ancient pottery culture and clay moulds used for bronze casting. [ABSTRACT FROM AUTHOR]

The spatial distribution of the aerosols over 86 Chinese cities was reconstructed from air pollution index (API) records for summer 2000 to winter 2006. PM10 (particulate matter ≤10 μm) mass concentrations were calculated for days when PM10 was the principal pollutant, these accounted for 91.6% of the total 150 428 recorded days. The 83 cities in mid-eastern China (100° E to 130° E) were separated into three latitudinal zones using natural landscape features as boundaries. Areas with high PM10 level in northern China (127 to 192 μg m-3) included Urumchi, Lanzhou-Xining, Weinan-Xi'an, Taiyuan-Datong-Yangquan-Changzhi, Pingdingshan-Kaifeng, Beijing-Tianjin-Shijiazhuang, Jinan, and Shenyang-Anshan-Fushun; in the middle zone, high PM10 (119-147 μg m-3) occurred at Chongqing-Chengdu- Luzhou, Changsha-Wuhan, and Nanjing-Hangzhou; in the southern zone, only four cities (Qujing, Guiyang, Guangzhou and Shaoguan) showed PM10 concentration >80 μg m-3. The median PM10 concentration decreased from 108 μg m-3 for the northern cities to 95 μg m-3 and 55 μg m-3 for the middle and southern zones, respectively. PM10 concentration and the APIs both exhibited wintertime maxima, summertime minima, and the second highest values in spring. PM10 showed evidence for a decreasing trend for the northern cities while in the other zones urban PM10 levels fluctuated, but showed no obvious change over time. The spatial distribution of PM10 was compared with the emissions, and the relationship between the surface PM10 concentration and the aerosol optical depth (AOD) was also discussed. [ABSTRACT FROM AUTHOR]

Superconducting Fault Current Limiter (SFCL) is an attractive appliance for modern electrical power system. A 10.5 kV/1.5 kA three-phase HTS fault current limiter was developed by IEE, CAS. This improved rectifier-type SFCL with HTS coil of 6.25 mH is going on a demonstrated long-term reliable operation in a real 10.5 kV substation located in Hunan, China. In a three-phase-to-ground short circuit test of grid, the prospective fault current of 3.5 kA was limited to 635 A at the pre-setup short-circuit point successfully. [ABSTRACT FROM AUTHOR]

Polycrystalline Cux O films produced by plasma oxidation are investigated for nonvolatile memory applications. Reversible bistable resistive switching from a high-resistance state to a low-resistance state, and vice versa, is observed in an integrated Al/Cux O/Cu structure under voltage sweeping. More than 3000 repetitive cycles are observed in 180-µm memory devices with an on/off ratio of ten times. Data testing shows that the devices meet the ten-year retention requirement for the storage of programmed logic signals. [ABSTRACT FROM AUTHOR]

The forming process, which is the first transition from fresh state to low resistance state, was investigated in CuxO memory films prepared by plasma-induced oxidation. X-ray photoelectron spectroscopy investigation of surface chemical bonds of CuxO films and Auger electron spectroscopy depth spectra show that the formation of a highly resistive CuO layer on the CuxO surface is the main reason for the requirement of a large forming voltage. After selectively deoxidizing the CuO into Cu2O, the need for the "forming" process disappears. [ABSTRACT FROM AUTHOR]

Developing and implementing biosafety standards for pathogenic microbiology laboratories is essential to achieving scientific, efficient, and standardized management and operation. This article analyzes the current standardization construction in biosafety in pathogenic microbiology laboratories domestically and internationally. It proposes a framework for the biosafety standard system of pathogenic microbiology laboratories, which mainly includes four parts: basic standards, management standards, technical standards, and industry applications. It provides a reference for the standardization work of pathogenic microbiology laboratories and helps to standardize the biosafety industry in China.