ALBERT

Description: A single-chamber microbial fuel cell (MFC) was used in this study to treat recycled stillage obtained from food waste ethanol fermentation. Corresponding substrates inside the system were evaluated by fluorescence spectra, and microbial communities were also investigated. Results demonstrated that output voltage and current, respectively, reached 0.29 V and 1.4 mA with an external resistance of 200 . Corresponding total organic carbon and chemical oxygen demand removal efficiency reached more than 50% and 70%, respectively. Results of fluorescence spectra demonstrated that tryptophan-like aromatic, soluble microbial by-product-like and humic acid-like substances accumulated and were not easily degraded. Microbial community analysis by high-throughput sequence indicated that Advenella and Moheibacter occupied the highest proportion among all genera at the anode instead of Geobacter . These results may be due to complicated accumulated stillage, and potential tetracyclines possibly influenced microbial communities. Details on how stillage affects MFC operation should be further studied, and a solution on relieving effects should be established.

Description: The structure of cucurbit[6]uril (CB[6]), as a fascinating supramolecular receptor, is regarded as ‘indestructible’. Herein, we investigated the hydrolysis of CB[6] catalysed by alkali. Our results showed that CB[6] was easily hydrolysed in 30% NaOH at 160°C within 3 h. Separation and purification of hydrolytic products demonstrated the presence of NH 3 , CO 2 , HCOONa, glycine and hydantoic acid. Based on the studies of the hydrolysis of substances similar to CB[6] including 4,5-dihydroxyethyleneurea, glycoluril and glycoluril dimer, we proposed that a plausible reaction mechanism involved a Cannizzaro reaction, which is supported by HPLC, mass spectrometry data and previous reports. Further studies are dedicated towards a controlled hydrolysis of CB[6], which will provide a new route for direct functionalization of CB[6].

Description: We describe a facile and low-cost approach for a flexibly integrated surface-enhanced Raman scattering (SERS) substrate in microfluidic chips. Briefly, a SERS substrate was fabricated by the electrostatic assembling of gold nanoparticles, and shaped into designed patterns by subsequent lift-up soft lithography. The SERS micro-pattern could be further integrated within microfluidic channels conveniently. The resulting microfluidic SERS chip allowed ultrasensitive in situ SERS monitoring from the transparent glass window. With its advantages in simplicity, functionality and cost-effectiveness, this method could be readily expanded into optical microfluidic fabrication for biochemical applications.

Description: Targeting fibroblast-like synoviocyte (FLS) migration and invasion-mediated bone erosion is a promising clinical strategy for the treatment of rheumatoid arthritis (RA). Drug sensitivity testing is fundamental to this scheme. We designed a microfluidic chip-based, cell co-cultured platform to mimic RA FLS-mediated bone erosion and perform drug-sensitive assay. Human synovium SW982 cells were cultured in the central channel and migrated to flow through matrigel-coated side channels towards cell culture chamber where RANKL-stimulated osteoclastic RAW264.7 and osteogenic medium (OS)-stimulated bone marrow mesenchymal stem cells (BMSC) were cultured in the microfluidic chip device, mimicking FLS migration and invasion-mediated bone erosion in RA. These SW982 cells showed different migration potentials to osteoclasts and BMSC. The migration of SW982 cells with high expression of cadherin-11 was more potent when SW982 cells were connected with the co-culture of RAW264.7 and BMSC. Simultaneously, in the co-cultured chamber, tartrate-resistant acid phosphatase (TRAP) activity of RANKL-stimulated RAW264.7 cells was enhanced, but alkaline phosphatase (ALP) activity was decreased in comparison with mono-cultured chamber. Furthermore, it was confirmed that celastrol, a positive drug for the treatment of RA, inhibited SW982 cell migration as well as TRAP activity in the cell-cultured microfluidic chips. Thus, the migration and invasion to bone-related cells was reconstituted on the microfluidic model. It may provide an effective anti-RA drug screen model for targeting FLS migration-mediated bone erosion.

Description: Cresol is a prototype molecule in understanding intermolecular interactions in material and biological systems, because it offers different binding sites with various solvents and protonation states under different pH values. It is found that the UV/Vis absorption spectra of o -cresol in aromatic solvents (benzene, toluene) are characterized by a sharp peak, unlike the broad double-peaks in 11 non-aromatic solvents. Both molecular dynamics simulations and electronic structure calculations revealed the formation of intermolecular -complexation between o -cresol and aromatic solvents. The thermal movements of solvent and solute molecules render the conformations of o -cresol changing between trans and cis isomers. The -interaction makes the cis configuration a dominant isomer, hence leading to the single keen-edged UV/Vis absorption peak at approximately 283 nm. The free conformation changes between trans and cis in aqueous solution rationalize the broader absorption peaks in the range of 260–280 nm. The pH dependence of the UV/Vis absorption spectra in aqueous solutions is also rationalized by different protonation states of o -cresol. The explicit solvent model with long-ranged interactions is vital to describe the effects of -complexation and electrostatic interaction on the UV/Vis absorption spectra of o -cresol in toluene and alkaline aqueous (pH 〉 10.3) solutions, respectively.

Description: Large intra-season differences in concentrations of CO and O3 ([CO], [O3]) were detected at Miyun, a rural site north of Beijing, in summer 2006. Despite an increase in mean daytime [CO] from 500 ppbv in June to 700 ppbv in July, mean daytime [O3] dropped from 67 ppbv in June to 50 ppbv in July and August. The observed changes in CO and O3 are attributed to the influence of the summer monsoonal circulation that develops over the North China Plain in July. Photochemical production of O3 is reduced as a consequence of increased cloudiness during July and August, as indicated by the strong negative correlation observed between [O3] and satellite observations of cloud optical depth, with cloudiness having little effect on CO. The analysis suggests a strategy for emission controls that could be implemented in an economically efficient manner to minimize the frequency of high levels of O3 during summer in Beijing.

Description: A series of aggressive measures was launched by the Chinese government to reduce pollutant emissions from Beijing and surrounding areas during the Olympic Games. Observations at Miyun, a rural site 100 km downwind of the Beijing urban center, show significant decreases in concentrations of O3, CO, NOy, and SO2 during August 2008, relative to August 2006–2007. The mean daytime mixing ratio of O3 was lower by about 15 ppbv, reduced to 50 ppbv, in August 2008. The relative reductions in daytime SO2, CO, and NOy were 61%, 25%, and 21%, respectively. Changes in SO2 and in species correlations from 2007 to 2008 indicate that emissions of SO2, CO, and NOx were reduced by 60%, 32%, and 36%, respectively, during the Olympics. Analysis of meteorological conditions and interpretation of observations using a chemical transport model suggest that restrictions on emissions during the Olympics were responsible for about 80% of the observed decreases in O3, with natural variations in meteorology accounting for the remaining 20%. Use of the Olympics emissions results in no significant biases between model and observations. The model predicts that emission restrictions such as those implemented during the Olympics can affect O3 far beyond the Beijing urban area, resulting in reductions in boundary layer O3 of 2–10 ppbv over a large region of the North China Plain and Northeastern China.

Description: A series of aggressive measures was launched by the Chinese government to reduce pollutant emissions from Beijing and surrounding areas during the Olympic Games. Observations at Miyun, a rural site 100 km downwind of the Beijing urban center, show significant decreases in concentrations of O3, CO, NOy, and SO2 during August 2008, relative to August 2006–2007. The mean daytime mixing ratio of O3 was lower by about 15 ppbv, reduced to 50 ppbv, in August 2008. The relative reductions in daytime SO2, CO, and NOy were 61%, 25%, and 21%, respectively. Changes in SO2 and in species correlations from 2007 to 2008 indicate that emissions of SO2, CO, and NOx were reduced at least by 60%, 32%, and 36%, respectively, during the Olympics. Analysis of meteorological conditions and interpretation of observations using a chemical transport model suggest that although the day-to-day variability in ozone is driven mostly by meteorology, the reduction in emissions of ozone precursors associated with the Olympic Games had a significant contribution to the observed decrease in O3 during August 2008, accounting for 80% of the O3 reduction for the month as a whole and 45% during the Olympics Period (8–24 August). The model predicts that emission restrictions such as those implemented during the Olympics can affect O3 far beyond the Beijing urban area, resulting in reductions in boundary layer O3 of 2–10 ppbv over a large region of the North China Plain and Northeastern China.

Description: Although China has surpassed the United States as the world's largest carbon dioxide emitter, in situ measurements of atmospheric CO2 have been sparse in China. This paper analyzes hourly CO2 and its correlation with CO at Miyun, a rural site near Beijing, over a period of 51 months (Dec 2004 through Feb 2009). The CO2-CO correlation analysis evaluated separately for each hour of the day provides useful information with statistical significance even in the growing season. We found that the intercept, representing the initial condition imposed by global distribution of CO2 with influence of photosynthesis and respiration, exhibits diurnal cycles differing by season. The background CO2 (CO2,b) derived from Miyun observations is comparable to CO2 observed at a Mongolian background station to the northwest. Annual growth of overall mean CO2 at Miyun is estimated at 2.7 ppm yr−1 while that of CO2,b is only 1.7 ppm yr−1 similar to the mean growth rate at northern mid-latitude background stations. This suggests a relatively faster increase in the regional CO2 sources in China than the global average, consistent with bottom-up studies of CO2 emissions. For air masses with trajectories through the northern China boundary layer, mean winter CO2/CO correlation slopes (dCO2/dCO) increased by 2.8 ± 0.9 ppmv/ppmv or 11% from 2005–2006 to 2007–2008, with CO2 increasing by 1.8 ppmv. The increase in dCO2/dCO indicates improvement in overall combustion efficiency over northern China after winter 2007, attributed to pollution reduction measures associated with the 2008 Beijing Olympics. The observed CO2/CO ratio at Miyun is 25% higher than the bottom-up CO2/CO emission ratio, suggesting a contribution of respired CO2 from urban residents as well as agricultural soils and livestock in the observations and uncertainty in the emission estimates.

Description: Large intra-season differences in mixing ratios of CO and O3 were detected at Miyun, a rural site north of Beijing, in summer 2006. Despite an increase in mean daytime mixing ratio of CO from 500 ppbv in June to 700 ppbv in July, mean daytime O3 dropped from 67 ppbv in June to 50 ppbv in July and August. The observed changes in CO and O3 are attributed to the influence of the summer monsoonal circulation that develops over the North China Plain in July. Photochemical production of O3 is reduced as a consequence of increased cloudiness during July and August, as indicated by the strong negative correlation observed between O3 and satellite observations of cloud optical depth, with cloudiness having little effect on CO. The analysis suggests a strategy for emission controls that could be implemented in an economically efficient manner to minimize the frequency of high levels of O3 during summer in Beijing.