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Objective：To explore the mechanism of posterior pilon fracture with different proportion of the medial malleolus involved and evaluate clinical outcomes of anterior-posterior screws fixation.Methods: Patients admitted to our hospital with diagnosis of tibial posterior Pilon fracture were identified from January 2014 to January 2018. Mechanism from medical history, proportion of the medial malleolus involved (not involved/partial involved /total involved) from axial CT sacn were recorded to figure out the mechanism . Burwell—Charnley radiographic criteria of reduction, American orthopaedic Foot＆Ankle society ankle-hindfoot scale at 12 month follow-up were recorded to evaluate the curative effect of anterior-posterior screws fixation.Result: Sixty-nine patients were identified in this retrospective study. 43 males and 26 females were included, with mean age 46.9 years old（range, 21-76 years）. Mechanism of the 8 cases with fracture line do not involve midial malleolus but accompanied with die-punch fragment included 4 ground level fall, 2 fall off stairs, 1 sport injury, 1 fall from bike. Mechanism of the 52 cases with midial malleolus partial involved included 14 motor vehicle accident, 14 fall off stairs, 5 sport injury, 3 fall from bike and 16 fall from height. Mechanism of the 9 cases with medial malleolus totally involved included 6 falling from height, 2 falling of stairs and 1 motor vehicle accident. Five patients were treated with the fixation of Anterior-Posterior screws, fracture line of four cases do not involve midial malleolus and the rest one partial involved. The Burwell—Charnley radiographic criteria of reduction were fair in 4 and poor in one on the post-operation X-ray. Three of them got implant failure. The AOFAS ankle-hindfoot scale 12-month post-operation for the rest two patients were 78 and 72.Conclusion: There is a high risk of implant failure using A-P screws for the treatment of posterior pilon fracture. The mechanism of posterior fracture involve medial malleolus is mainly vertical force .

To overcome the inherent complexity of lignocellulosic biomass and improve its biological conversion efficiency, the central composite surface response methodology was used to optimize the process variables (temperature, reaction time and liquid-to-solid ratio) in liquid hot water pretreatment for biomethane production from the anaerobic digestion of Hybrid Pennisetum (a typical energy crop in southern China). Temperature, reaction time and water content were varied between 160–200 °C, 20–60 min and 60–90 mL respectively. The biomethane yields from pretreated material were considered as response variables to different processes conditions. Results showed untreated Hybrid Pennisetum had a biomethane potential of 218.6 L/kg volatile solid (VS) (corresponding to a biodegradability of 62.6%). The effect of liquid hot water pretreatment on the biomethane yield was distinct. Pretreatment severities less than 4.55 resulted in increased biomethane yields. However, further increasing the severity led to lower biomethane yields. The optimum biomethane yield (290.6 L/kg VS) was obtained from pretreated Hybrid Pennisetum at 175 °C for 35 min, with the highest biodegradability of 83.2%. Energy balance showed that, under the optimal pretreatment condition, the highest energy conversion efficiency of 76.1% was attained in theory. If the process energy inputs are included, a process energy efficiency of 51.7% could be realized with proper heat recovery.

This study investigated whether bioaugmentation can improve the anaerobic digestion (AD) performance of food waste (FW), as well as the effects of addition dosage and frequency on the bioaugmentation’s performance and economic feasibility. The findings demonstrated that all the bioaugmented digesters, regardless of dosage and frequency, performed more effectively in biogas production than the non-bioaugmentation control. Furthermore, relatively higher dosages or frequencies increased AD performance. Introducing 0.25 g L−1 d−1 of bioaugmentation seed every three days increased OLR and volumetric biogas production 8-fold and 12-fold, respectively, compared to the non-bioaugmentation control. Whole-genome sequencing analysis showed that bioaugmentation enhanced the population of the acetoclastic Methanothrix (belong to the order Methanosarcinales). Moreover, high abundance of Methanothrix (exceeding 80%) contributed to a better AD performance. Economic analysis of an up-scale biogas plant suggested that an appropriate bioaugmentation process increased income, thus increasing the profit to 3696 CNY d−1 if treated at 21 t FW.

This study is the first to integrate gamma-valerolactone/water (GVL/water) pretreatment with anaerobic digestion (AD) for biogas production and lignin nanoparticles (LNPs) synthesis. The hydrothermal treatment was conducted at 135 to 180 °C with GVL at 0 to 90%. After pretreatment, the compositions of hybrid pennisetum were changed with the removal of lignin, hemicellulose, and cellulose to different extent. Subsequent anaerobic digestion achieved a maximal specific methane yield of 228.00 ± 4.37 mL/g VS, compared with that at 165.11 ± 1.99 mL/g VS for the control. The highest actual methane yield (150 mL/g RM) was achieved by pretreatment with GVL/water (50/50) at 150 °C for 90 min. LNPs at 200 to 2000 nm were synthesized from the liquid waste with a yield at ~4 mg/mL. The mass balance of this integrated method was discussed. In general, the maximal valorisation of hybrid pennisetum was achieved based on a catalyst-free of GVL/water pretreatment.

Microalgae have been considered as one of the most promising biomass resources for the generation of biodiesel, whereas algal residues (AR) after lipid extraction need to be utilized to enhance its economy and sustainability. This study proposed an integrated biochemical method for microalgae Chlorella sp. processing to achieve a high energy yield (12.33 KJ g−1VS). The microalgae were first pretreated with mixed enzymes for lipid extraction. After that, the AR obtained from the lipid extraction of microalgae was co-digested with energy grass (GR) Pennisetum hybrid for methane production. Results indicated that the lipid yield from microalgae was enhanced by 54.45% with mixed enzymes pretreatment of cellulase, xynalase and pectinase compared to that without enzymatic pretreatment. The maximal methane yield (207.35 ± 15.66 mLCH4 g−1VS) of AR and GR co-digestion was obtained with the AR and GR VS ratio at 1:3. Energy yields evaluation based on the biodiesel and methane yields indicated that the energy yield for this two-step combined method was 169% higher than that for biodiesel alone. Thus, the proposed integrated approach was verified to be applicable for microalgae processing for energy production.

Cell wall disruption is an essential downstream processing step for improving the efficiency of lipid extraction from microalgae. Enzyme-assisted extraction of lipid from microalga Scenedesmus sp. with cellulase, xylanase and pectinase, using various parameters, such as enzyme concentration, temperature, pH and incubation time, was optimized by central composite design (CCD) coupled with response surface methodology (RSM). Both the lipid extraction from microalgae and the fatty acid methyl esters (FAMEs) production under optimal conditions showed a ∼twofold in the yields compared to the control group with no enzymatic treatment. SEM images, FTIR measurement, XPS and HPLC analysis showed that the enzymatic pretreatment caused significant alterations in the cell wall structure of microalgae. And the disruption of microalgal cell walls was primarily attributed to the breakage of β-glucosidic linkages in cellulose and hemicellulose. The study showed a promising approach can lead to an improvement in the lipid extraction yield from microalgae and further provide valuable information for the use of enzymes in microalgal processes.

This study aims to investigate the performance of bioaugmentation with an acid-tolerant methanogenic culture to recover deteriorated anaerobic digestion caused by organic overloading. The function of bioaugmentation was evaluated in terms of substance metabolism, microbial community structure, and gene function. Our findings demonstrate that routine bioaugmentation effectively recovered the failing digester by degrading accumulated volatile fatty acids and increasing pH. In contrast, a non-bioaugmentation reactor (control) did not recover by itself, while abiotic augmentation restored the digestion performance temporarily but the digester failed again at an organic loading rate of 1.5 g L−1 d−1. Using whole genome pyrosequencing analysis, we found that after bioaugmentation, the populations of Methanothrix (acetoclastic methanogens) and Methanolinea (hydrogenotrophic methanogens) increased significantly, which may be the main contributors for the positive effect on methane production. On the genic level, bioaugmentation may enhance the function of genes involved in cell motility, signal transduction mechanisms for methanogens, and energy production and conversion for bacteria.

The anaerobic digestion (AD) performance for breakfast, lunch, and dinner kitchen waste (KW) produced by the canteen at Guangzhou University was assessed by a batch experiment under mesophilic and thermophilic conditions. The AD concentrations were 9.54 g VS/L, 20.12 g VS/L, and 39.99 g VS/L, respectively. The concentration of 20.12 g VS/L under thermophilic conditions had the best AD performance among all the KW. The maximum specific methane yield of 591 ± 30 mL/g VS was obtained from dinner KW (D-KW). Due to the differing organic composition, the specific methane yield of D-KW and lunch KW (L-KW) was 41.16% and 19.76% higher than that of breakfast KW (B-KW) under the optimal condition, respectively, whereas that of D-KW was 17.96% higher than that of L-KW. The specific methane yield was significantly correlated to the crude fat content. When the concentration was increased to 39.99 g VS/L, accumulation of toxic materials was observed and the AD process stopped. The potential biogas yield, based on production of 5904.43 tons of KW per year at the Guangzhou Higher Education Mega Center (HEMC), is 1.08 million m3 biogas, equivalent to 2.15 million KW h of electricity.

This study investigated the co-digestion performance of Pennisetum hybrid and cow manure via batch mode tests to optimize the feedstock ratio. On the basis of the batch test results, the long-term operational performance of the co-digestion system at different ratios was assessed at mesophilic temperature and organic loading rates (OLRs) of 2.0–5.5 g of volatile solids (VS) L–1 day–1 via semi-continuous mode. Batch tests showed that the maximum specific methane yield of 170.35 ± 11.61 mL/g of VS was obtained at a Pennisetum hybrid/cow manure ratio of 100:0, with the specific methane yield decreasing with an increased proportion of cow manure. In the semi-continuous experiments, the mono-digestion of Pennisetum hybrid failed at the OLR of 2.0 g of VS L–1 day–1. This failure was accompanied by the accumulation of volatile fatty acids (VFAs). The stable operational OLR increased by 1.0–1.5 times with the addition of cow manure. The volumetric biogas yield increased with the augmentation of the OLR from 2.0 t...

The acid-tolerant methanogenic propionate degradation culture was acclimated in a propionate-fed semi-continuous bioreactor by daily adjusting the digestate pH. The performance of propionate fermentation, the respond of microbial community structure to the acidic environment, and the microbial network for propionate degradation in the acid-tolerant culture was investigated. The results demonstrated that after long term of acclimation to low pH, the digester could produce methane from propionate at pH 4.8–5.5 with 0.3–0.4 L g−1 propionic acid (HPr) d−1 of the volatile solids (VS) methane production. The predominant methanogens shifted from acetoclastic methanogens (∼87%) to hydrogenotrophic methanogens (∼67%) in the bioreactor with the dropping pH, indicating that hydrogenotrophic methanogens were more acid-tolerant than acetoclastic methanogens. Smithella (∼11%), Syntrophobacter (∼7%) and Pelotomaculum (∼3%) were the main propionate oxidizers in the acid-tolerant propionate-utilizing culture. Methanothrix dominant acetoclastic methanogens, while Methanolinea and Methanospirillum were the major H2 scavengers to support Syntrophobacter and Pelotomaculum syntrophic propionate degradation.

Intercropping improves yield and is broadly adopted worldwide; however, the risk and regulatory mechanism of nitrate leaching in intercropping compared with monocropping remain elusive. A fixed plot field experiment was conducted with three cropping patterns (maize monocropping, potato monocropping, and maize–potato intercropping) under four (nitrogen) N levels in Kunming, China during 2014–2017. Based on crop N uptake and soil nitrate transformation, the underlying mechanism of potential nitrate-N (NO3−-N) leaching (NO3−-N accumulation below the root layer) and N regulation was explored under intercropping and monocropping. The results showed that the area-scaled potential NO3−-N leaching under intercropping was mitigated by 3.4–37.4%, with a mean of 15.8% relative to the weighted mean of maize- and potato-monocropping. Intercropping-related mitigation of potential NO3−-N leaching was enhanced with increasing N level. Intercropping increased the ammonia-oxidizing archaea population and soil nitrification potential but had no significant impact on the abundance of ammonia-oxidizing bacteria and narG. Redundancy analysis and structural equation modeling indicated that soil water played a crucial role in regulating the intercropping-related mitigation of potential NO3−-N leaching, while the improvement in N uptake by intercropped maize reduced the potential NO3−-N leaching at low and medium N levels. The results highlight the intercropping advantage over monocropping in mitigating the risk of NO3−-N leaching. This study provides insights into the environmental impacts of diversified cropping systems and regulating mechanisms.

The methanogenic propionate degradation consortia were enriched in a propionate-fed semi-continuous bioreactor. The microbial community shift with depth, the microbial network and its correlation with metabolic pathway were also investigated. The results demonstrated that the maximum organic loading rate (OLR) of the reactor was 2.5 g propionic acid (HPr) L−1 d−1 with approximately 1.20 LL−1 d−1 of volumetric methane production (VMP). The organisms in the enrichment were spanning 36 bacterial phyla and 7 archaeal orders. Syntrophobacter, the main Hpr oxidizer in the digester, dominated bacteria with relative abundance changing from 63% to 37% with depth. The predominant methanogens shift from hydrogenotrophic Methanoculleus (∼60%) at the upper liquid layer to acetoclastic Methanothrix (∼51%) at the lower sediment layer in the bioreactor. These methanogens syntrophically support Syntrophobacter by degrading HPr catabolism by-products (H2 and acetate). Other bacteria could scavenge anabolic products (carbohydrate and protein) presumably derived from detrital biomass produced by the HPr-degrading community.

The effect of variable sodium concentrations on the anaerobic digestion performance of Sargassum sp. was investigated, and the variation in bacterial and archaeal communities was analyzed by high-throughput gene sequencing. Results showed that the maximum methane yield of 290.41 ± 34.21 mL of CH4 g–1 of volatile solids was obtained at a sodium concentration of 4.42 g L–1, increased by 38.1% compared to the control group. Meanwhile, higher volatile fatty acids production was observed at the sodium concentration of 4.42 g L–1. The inhibitory concentration values of 10%, 50%, and 90% occurred at the sodium concentrations of 6.3, 11.3, and 18.7 g L–1, respectively. The hydrolytic, acidogenic, and acetogenic bacteria and the hydrogenotrophic methanogens could normally metabolize at sodium concentrations of 2.46–24.08 g L–1, whereas the acetoclastic methanogens were severely inhibited at sodium concentrations greater than 20.15 g L–1. The microbial community structure showed that Paludibacter and Fibrobacter pl...

BACKGROUND Propionate accumulation may lead to digester failure. This study aimed to investigate the effect of ammonia, a metabolic product of protein, on propionate degradation. The shift of microbial community was also investigated. RESULTS Propionate accumulated over the experimental period in the reactor with a total ammonia nitrogen (TAN) concentration of 2.5 g N L−1, as a result the digester failed after 4 hydraulic retention times (HRT) at an organic load rate (OLR) of 0.8 g propionic acid (HPr) L−1 d−1. The average HPr degradation rate was below 54% during the fourth HRT, while >97% of the degraded HPr was converted to methane. The reactor without ammonia stress did not experience HPr accumulation and OLR was increased stepwise to 1.2 g L−1 d−1 at the 8th HRT. The average HPr degradation rate and methane recovery rate of this reactor in the last HRT was 99% and 74%, respectively. According to the shifts of microbial community, acetoclastic methanogen was more vulnerable to ammonia than hydrogenotrophic methanogen CONCLUSION TAN concentration of 2.5 g N L−1 inhibited propionate degradation more severely than methanogenesis. The loss of abundance of Clostridiaceae and Syntrophobacter might be the main reason for the poor performance under ammonia stress. © 2017 Society of Chemical Industry

BACKGROUND The main obstacle associated with methane production in anaerobic digestion processes from marine macroalgae is inhibited by the sea salts. This study aims to investigate the anaerobic digestion performance of marine macroalgae by acclimating inoculum to varying salinity, and to analyze the influence of salinity on microbial community by high-throughput gene sequencing. RESULTS The relationship between specific methane yield and salinity followed the third-order polynomial equation: y = 271.533 + 6.449X − 0.261X2 + 0.002X3. The acclimating inoculum produced methane efficiently at 35 g L−1 with a specific methane yield of 220.88 mL CH4 g−1 VS. Methanogenesis was considerably impeded at salinity greater than 55 g L−1. The bacterial phyla Bacteroidetes, Firmicutes, and Proteobacteria and the Methanobacterium, Methanosaeta, and Methanosarcina genera in archaea were predominant at different salinities. Hydrogenotrophic methanogens such as Methanobacterium can tolerate salinity up to 85 g L−1, whereas acetoclastic methanogens, Methanosaeta and Methanosarcina were severely inhibited at salinity greater than 65 g L−1. CONCLUSION The acclimating inoculum can be used as anaerobic microbial resources for efficient methane production from marine macroalgae under seawater conditions of 35 g L−1. The hydrolytic, acidogenic, acetogenic bacteria and hydrogenotrophic methanogens normally metabolized at different salinities, whereas acetoclastic methanogens were severely inhibited at high saline conditions. © 2017 Society of Chemical Industry

Visible light mediated photoredox arylations can proceed under very mild conditions and have therefore become attractive. Nowadays, various metal nanomaterials and metal complexes have been developed as photocatalysts for direct arylation of heteroaromatics. These photocatalysts, however, still suffer from corrosion, high cost, aggregation or poor stability. We report the design and fabrication of a g-C3N4/rGO nanocomposite and demonstrate its excellent activity, high apparent quantum efficiency, and recyclability to catalyze the metal free direct arylation of heteroaromatics under visible light at room temperature. Moreover, the g-C3N4/rGO catalyst can be reused more than five times without significant loss of activity, confirming this catalyst's excellent stability. The present strategy to fabricate a metal-free g-C3N4/rGO nanocomposite for direct C–H arylation open a new avenue towards replacing metal-based catalysts in fine organic synthesis.

To enhance the biodegradability and methane production of hybrid Pennisetum, a pretreatment method with high selectivity for lignin removal, namely sodium chlorite/acetic acid (SCA) pretreatment, was examined in this work. Results showed that SCA pretreatment can selectively remove lignin with minimal impact on cellulose and hemicellulose. After up to 200 min of SCA treatment, 79.4% of lignin was removed and over 90% of the holocellulose was retained. The physicochemical changes after pretreatment were analyzed by confocal laser scanning microscopy, X-ray diffractometer and Fourier transform infrared spectroscopy, showing that the majority of lignin was removed from secondary cell walls and cell middle lamella while the chlorite-resistant lignin remained in the cell corner. Lignin removal significantly enhanced the biodegradability from 59.6% to 86.4% and increased methane production by 38.3%. Energy balance showed that SCA pretreatment was efficient to increase the energy output of hybrid Pennisetum.

The biomass of grass-based Pennisetum hybrid commonly use for a biogas production via anaerobic digestion. However, it is necessary to determine a method to optimize the plant harvest time for high biogas production. Moreover, ensiling of biomass in the presence of diverse microbes may offer a solution to improve biogas production. In this study, whole plant of Pennisetum biomass (including stems and leaves) was collected at different harvesting time (plant heights of 70, 100, 150 cm), and then comparatively assessed for further ensiling and biogas production. Compared to leaves, stems exhibited a significant linear relationship (R2 = 0.99) with whole plants in terms of ensiling quality (i.e. pH and NH3-N). Microbial analysis further revealed that Lactobacillus was the dominant bacterial genus during ensiling of stems and whole plants, with the highest relative abundance of 50.08% obtained at the height of 100 cm. Ensiling of biomass at a height of 100 cm achieved the best digestion performance, with the methane yields of 316 ± 20 mL/g VS for leaves, 361 ± 43 mL/g VS for stems, and 356 ± 28 mL/g VS for whole plants. A harvesting time at the plant height of 100 cm was the optimal from the silage quality and anaerobic digestion performance.

Bioresource evaluation is prerequisite and important to reduce cost of feedstock collection and avoid battle for feedstock to promote the healthy development of bioenergy industry. This study estimated Thai bioresources from arable field crops, horticultural plants and livestock with product quantity or livestock number, residue-product ratio or manure productivity, and moisture content. Rice straw and husk, para rubber residues and cattle manure separately have the top amount in arable field crop biomass, horticultural residues and livestock manures. The northeastern region has the most amounts of arable field crop biomass and livestock manures, and the southern region possesses the largest quantities of horticultural residues. The available energy potentials from residues of arable field crops and horticultural plants can reach to maximum of 4.91 × 105 TJ and 7.65 × 105 TJ, respectively, which can theoretically share 21.67% of current total primary energy supply. The available biogas potential from livestock manures is nearly ten times than its current generation. After analysis the status of technologies and government policies for Thai bioenergy industry, it indicates that the utilization of bioenergy in the form of electricity, heat and transportation fuels has promising prospect in Thailand. The provinces of Thailand which are more suitable for developing bioenergy industry are suggested. This work may guide the reasonable layout of bioenergy industry in Thailand via the presence of bioresouces distribution in every province.

In this study, batch experiments were conducted to compare the effect of temperature and substrate source on microbial communities in the anaerobic digestion of kitchen waste. The results showed that the microbial communities of anaerobic digestion were not sensitive to varied sources of waste, but shifted with the change in operating temperatures. In the reactors operated at mesophilic conditions, Levilinea, Syntrophomonas, Methanothrix, and Methanosphaerula, etc. were the dominant microbes during the process. While in thermophilic reactors, Levilinea, Ornatilinea, Methanosphaerula and Methanomassiliicoccus, etc. prevailed. Meanwhile, an enrichment in Coprothermobacter, Defluviitoga, Defluviitalea, Tepidimicrobium, Lutispora and Fonticella were observed as the temperature changed from mesophilic to thermophilic, suggesting these genera could be selectively enriched at thermophilic conditions. The results provided fundamental understanding of the microbiology that could support the scale up of food waste anaerobic digestion.

The effect of additives on the silage quality, microbial community, and anaerobic digestion performance of Pennisetum purpureum with high moisture content was studied. The sample treated with a mixed additive had best silage quality with the lowest pH and highest lactic acid/acetic acid ratio. Different additives influenced the dominant desirable bacteria. Correspondingly, Enterobacter was the dominant bacterial genus for sample with non-fermentative additives, whereas for the samples with fermentative or mixed additives, both Enterobacter and Lactobacillus had high relative abundance. The parameters of NH3-N, hemicellulose and lactic acid were positively correlated with the specific methane yield, while the lignin content was inversely correlated with the specific methane yield. The higher specific methane yield of 293.81 ± 0.15–334.69 ± 22.75 mL/g VS was obtained for samples treated with fermentative additive. Therefore, the mixed additive and fermentative additive are recommended for the silage of material with high-moisture content to improve the silage quality and methane yield.

A three-axis atomic magnetometer for nuclear magnetic resonance gyroscopes (NMRGs) is demonstrated. To satisfy the miniaturization demand of NMRGs, a magnetic-resonance-based atomic magnetometer is used to detect the longitudinal magnetic field. Simultaneously, the longitudinal field is modulated to measure the magnetic field in x and y axes based on a nonlinear magneto-optical rotation magnetometer. Magnetic field sensitivities of 100 fT/Hz1/2 in x and y axes and 20 fT/Hz1/2 in the z axis are achieved. The bandwidths of this magnetometer are 96 Hz in x and y axes and 6 Hz in the z axis. A high-sensitivity three-axis magnetometer is essential to accomplish the rotation detection in NMRGs and also plays a vital role in optimizing the performance of gyroscopes.

We report on the realization of modulation transfer spectroscopy on the D2 transition of 133Cs for frequency stabilization of the 852 nm distributed Bragg reflector diode lasers. Proper modulation frequency, optimal pump and probe beam power are investigated according to the peak-to-peak amplitude and the slope of the modulation transfer spectroscopy signals. The laser frequency can be locked robustly for more than one day. The beat signal between two independent lasers has a frequency drift of 716 kHz at 5000 s. The result shows that the fractional frequency instability of the locked laser falls below 5 × 10−11 at 1000 s averaging time.

Three-dimensional networks composed of one-dimensional nanomaterials are widely used in electrocatalysis owing to their high charge transfer efficiencies. In this study, we report a hydrothermal lysine-assisted route for the synthesis of the Pd nanochain networks (Pd NCNs). In addition, we demonstrate the application of Pd NCNs in microbial fuel cells (MFCs), which represent a promising technology for wastewater treatment that also directly generates electrical energy. The Pd NCNs exhibit superior activity for the oxygen reduction reaction under neutral conditions because of their unique structure and down-shifted Pd d-band center, as compared with the commercial Pd black catalyst. The maximum power density generated in a membraneless single chamber MFC operating on wastewater with the as-prepared Pd NCNs as cathode catalysts is ~14.10 W m−3 or 563.99 mW m−2, which remains stable for over 100 days, clearly demonstrating the potential application of Pd NCNs in MFCs.

Elephant grass might be a potential source of fine chemical precursors and bioenergy. In the present study, we investigated the dynamics of hydrolysis of elephant grass. Three models were used to fit the hydrolysis rate constants—flat, spherical, and cylindrical models. The hydrolysis rate constants obtained using the spherical model presented the best fit between the experimental and theoretical values. Furthermore, we determined the secondary reinforcement points and interventions that can be introduced to speed up the hydrolysis process. Our findings will provide information for studies on the hydrolysis of elephant grass and promote its application in the biogas industry as an alternative biofuel.

To investigate whether bioaugmentation could improve the digestion performance of high C/N ratio feedstock without co-digestion with nitrogen-rich substrate, different forms of enriched methanogenic culture were introduced to the continuous feed digesters. The performance efficiency of bioaugmentation on digestion improvement was compared. The effect of bioaugmentation on microbial community composition was revealed as well. Results demonstrated that routine bioaugmentation with liquid culture (containing the microbes and the medium remains) showed the best performance, with the organic loading rate (OLR), methane percentage, volumetric methane production (VMP) and volatile solid methane production (VSMP) higher at 1.0 g L−1 d−1, 24%, 0.22 L L−1 d−1 and 0.23 L g−1 VS d−1 respectively, compared to the non-bioaugmentation control. Whole genome pyrosequencing analysis suggested that consecutive microbial consortium addition could reconstruct the methanogens community by increasing the populations of acetoclastic methanogens Methanothrix, which could accelerate the degradation of acetate and methane production.

Goals are constructs that direct choice behavior by guiding a decision maker toward desirable (or away from undesirable) end states. Often, consumers are motivated to satisfy multiple goals within a single choice. Although previous research has recognized this possibility, it has not directly formulated models of choice as a multigoal problem. The authors develop such a model, referred to as the multiple-goal-based choice model, which incorporates (1) simultaneous multiple goal pursuit and (2) context-driven goal adaptation but (3) does not require a priori identification of the number or nature of the goals. Goal adaptation within a single choice instance, allied to repeated choices, is the key to empirical identification of multiple latent goals. The proposed model is tested and supported using discrete choice experimental data on digital cameras through multiple validation exercises. The model can lead to significantly different policy implications with regard to consumers’ valuation for new product designs, compared with extant utility-based choice models.

Random utility models have been widely employed in environmental valuation. But stochastic choice set formation models in the random utility framework are rarely applied in this literature, although previous research has shown that ignoring choice set formation (when it exists) leads to biased parameter estimates and welfare measures. This paper conducts Monte Carlo (MC) experiments to investigate the directionality and magnitude of welfare measure bias arising from ignoring or misspecifying choice set formation. We find that when attribute cutoff-based choice set formation exists in the data generation process, typical RUM models ignoring or misspecifying choice set formation underestimate welfare measures by 30-50%. Models that approximate choice set formation may produce unbiased welfare measures, but constitute a promising area for future research. This paper illustrates the importance of applying choice set formation in environmental valuation and provides practical guidance about the usage of stochastic choice set formation models. Refereed/Peer-reviewed

Material flow analysis (MFA) was applied to study the process of biogas production from switchgrass using a mid-temperature (35 ± 1 °C) batch anaerobic digestion process. The flow distributions of energy and material, including carbon (C) and nitrogen (N), were analyzed, as were the material and energy conversion efficiencies. The results showed that biogas and CH4 production were 268.80 and 135.31 NmLgVS-1 added, respectively, and the average CH4 content in biogas was 50.34%. Based on the MFA of the anaerobic digestion process, 30.6%, 3.6%, and 65.8% of C was converted into biogas, biogas slurry, and biogas residue, respectively; and 11.7% and 88.3% of N was converted into biogas slurry and biogas residue, respectively. The conversion efficiencies of the material and energy from switchgrass to biogas were 36.1% and 30.1%. Because of the low conversion efficiencies of matter and energy during biogas production, it is necessary to strengthen the secondary use of the fermentation residue. This study provides a basis for the optimization of the anaerobic digestion process and efficient utilization of resources and energy of energy-grass.

Benzothiadiazole (BTH) is an artificial inducer of systemic acquired resistance. Due to rice being an important food crop and model plant, we investigated its response to BTH using label-free proteomics technology coupled with bioinformatics. Protein expression levels were verified using the multi-reaction monitoring mode and semi-quantitative RT-PCR. BTH treatment can up- or down-regulate many proteins produced by the rice host at all four periods, with the numbers of proteins being 6/24, 9/10, 14/10, and 8/20, respectively. Compared with mock treatments (phosphate buffered saline with 0.1 % dimethylsulfoxide and 0.5 % Tween-20), some proteins related to plant resistance were only detected after BTH treatments, such as ascorbate peroxidase (POD) 3, chitinase A, thioredoxin-dependent POD 2, beta-1,3-glucanase 2, POD superfamily protein, major facilitator superfamily (MFS) protein, copper/zinc-superoxide dismutase (SOD) 1, pathogenesis-related protein (PR) 1. Other proteins showing up-regulation after BHT treatment included PR-5, glyceraldehyde-3-phosphate dehydrogenase C, plasma-membrane associated cation-binding protein 1, and oxidoreductase family proteins. These results indicated that BTH was involved with inducing rice resistance. Some up-regulated proteins were also involved in other metabolic processes. The activity and expression level of POD, phenylalanine ammonia-lyase (PAL), and SOD, lipoxygenase (LOX), beta-1,3-glucanases, and chitinases were determined using the enzyme activity assay and semi-quantitative RT-PCR. These results indicated that BTH can enhance the activity of beta-1,3-glucanases, LOX, PAL, and POD. BTH can also induce up-regulation of the copper/zinc-SOD, ascorbate POD, glutathione POD 1, Chitinase, and LOX1 genes.

Alkaline pretreatment with NaOH was used to improve methane yield from Pennisetum Hybrid. The pretreatments were carried out with different NaOH solutions (2–8% w/w) at three temperatures (35, 55 and 121 °C) for different periods of time (24, 24 and 1 h). All treated and untreated Pennisetum Hybrid were digested under mesophilic conditions (37 °C) to biogas, significant effects of the pretreatments on the yield of methane were observed. Results showed the modified Gompertz equation was reliable (determination coefficients (R2) greater than 0.96) to describe the kinetic behavior of anaerobic digestion of Pennisetum Hybrid. The best result, obtained by the treatment at 35 °C 2% NaOH for 24 h, resulted in the methane yield of 301.7 mL/g VS, corresponding to 21.0% improvement in the methane yield. Compositional, SEM, XRD and FTIR analysis confirmed that lignin removal, structural modification and cellulose crystalline variation were responsible for the improvement.

The silage quality and anaerobic digestion performance of Pennisetum purpereum with molasses-processed wastewater addition were assessed. The silage samples with molasses-processed wastewater addition obtained higher lactic acid concentration of 15.18-23.38mg/g FM, lower pH value of 3.96-4.45 and lower NH3-N content of 0.47-0.64mg/g FM. No obvious difference was observed in the dominant phyla and genus, but the relative abundance of Lactobacillus reached up to 77.39%, increased by 84% compared to the silage samples without molasses-processed wastewater addition. Combined the silage quality and bacterial community, the decreased in pH value of fresh material caused by molasses-processed wastewater addition was the main reason for improving the silage quality. Meanwhile, the increased in COD concentration is beneficial for improving the specific methane yield and the maximum specific methane yield of 259±5.75mL/g VS was obtained with adding 20g/kg molasses-alcoholic wastewater. Molasses-processed wastewater is an alternative additive for silage.

Sine oculis homeobox homolog 1 (SIX1) protein is a member of the homeobox transcription factor family. Overexpression of SIX1 contributes to cancer progression and is associated with adverse outcomes in various cancer types including breast, ovarian, uterine cervical and liver. To investigate the clinicopathological significance of SIX1 protein expression in gastric adenocarcinomas (GAC), localization of the SIX1 protein was determined in MKN-1, a gastric cancer cell line, using immunofluorescence (IF) staining; SIX1 mRNA level was detected in fresh tissues of GAC and normal gastric mucosa using quantitative real-time polymerase chain reaction (qRT-PCR); and SIX1 protein expression was assessed in 163 GAC, 35 gastric dysplasia and 26 normal gastric mucosa using immunohistochemical (IHC) staining. Correlations between SIX1 protein expression and pathological parameters of GAC were analyzed using Chi-square tests, differences in survival curves were analyzed using log-rank tests, and multivariate survival analysis was performed using the Cox proportional hazards regression model. SIX1 protein showed a mainly cytoplasmic staining pattern in GAC using IF and IHC staining. The positive SIX1 protein expression rate was 80.4% in GAC, which was significantly higher than in either gastric dysplasia (45.7%) or normal gastric mucosa (26.9%) (P

Runt-related transcription factor 3 (RUNX3) has recently been reported to be a possible predictor of sensitivity of cancer cells for photodynamic therapy (PDT), a promising therapeutic modality for keloids. In this study, we aimed to elucidate the implications of RUNX3 for keloid pathogenesis and sensitivity to pheophorbide a-based PDT (Pa-PDT). RUNX3 and proliferating cell nuclear antigen (PCNA) expression were examined in 6 normal skin samples and 32 keloid tissue samples by immunohistochemistry. We found that RUNX3 expression was detected more often in keloid tissues than in dermis of normal skin. In keloid tissues, RUNX3 expression was significantly increased in patients presenting with symptoms of pain or pruritus, and was also significantly related to PCNA expression. The therapeutic effect of Pa-PDT was comparatively investigated in keloid fibroblasts (KFs) with and without RUNX3 expression. Significant differences were found after Pa-PDT between KFs with and without RUNX3 expression in cell viability, proliferative ability, type I collagen expression, generation of reactive oxygen species (ROS), and apoptotic cell death. In addition, RUNX3 expression was significantly decreased after Pa-PDT in KFs, and KFs with downregulation of RUNX3 showed significantly increased cell viability after Pa-PDT. Pa-PDT may be a potential therapeutic modality for keloids, and RUNX3, as a possible contributor to keloid pathogenesis, may improve sensitivity to Pa-PDT in KFs.

The catalytic activity of surface-modified carbon powder, Vulcan XC-72R (XC), for the oxygen reduction reaction (ORR) at an air cathode in a microbial fuel cell (MFC) has been investigated. The effects of treatment with different chemicals such as nitric acid and ammonia on the chemical characteristics of XC were studied. The catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), Boehm titration, and X-ray photoelectron spectroscopy. FTIR analysis showed that the functional groups of the materials were changed by chemical treatment, with nitric acid causing the introduction of oxygen-containing groups, and ammonia leading to the introduction of nitrogen-containing groups. Electrochemical measurements of MFCs containing various modified carbon materials as ORR catalysts were performed, and the results showed that chemically modified carbon materials are promising catalysts in MFCs.

Microbial fuel cell (MFC), which can directly generate electricity from biodegradable materials, has been receiving increasing attention. Effects of temperature change on power density, electrode potential, columbic efficiency, chemical oxygen demand removal and internal resistance in two chambers MFCs were examined in this paper. The maximum power density of 7.89 W/m3 was achieved at 37 degrees C, with 199% higher at 10 degrees C (2.64 W/m3), 24% higher at 30 degrees C (6.34 W/m3) and 21% higher at 43 degrees C, no steady power generation was observed at 55 degrees C. Low temperature to 10 degrees C might have a huge effect on anode potential, especially at higher current, but increasing the temperature to 43 degrees C had a main effect on the cathode performance when the MFCs have been established at 37 degrees C. The internal resistance of MFC was about 29 omega at 37 degrees C, and increased 62% and 303% when MFC switched to 30 degrees C and 10 degrees C. Similarly, internal resistance increased 48% at 43 degrees C. The effect of temperature on MFC performance was expressed by internal resistance, the higher the internal resistance of MFC, the lesser the power density obtained. The Columbic efficiencies were 8.65% at 30 degrees C, 8.53% at 37 degrees C, and 13.24% at 43 degrees C. These results demonstrate that MFCs can effectively be operated over a wide range of temperatures.

Using cross-sectional survey data on prices, station and market characteristics for 730 gasoline stations in the Greater Saint Louis area, we estimate a switching regression model of station decisions. We employ a binary probit choice model to study a station’s decision to enter a contract relationship with greater control from the upstream refinery, or a contract relationship with greater degree of independence, as a function of market and station characteristics. We then estimate stations’ pricing decisions with self-selectivity corrections for the station’s contract decision. We show that incorrect inferences about retail gasoline station’s pricing behavior would result if the endogeneity in the choice of con-tract type were treated as exogenous condition in the estimation.

The biomass yield and mesophilic anaerobic digestion performance of Pennisetum hybrid that were collected at different harvest periods and cutting frequencies were investigated. Results indicated that chemical composition, biomass yield, and specific methane yield of Pennisetum hybrid were significantly influenced by harvest period and cutting frequency. The contents of total solids, volatile solids, carbon, cellulose, lignin and starch increased with a prolonged harvest period, whereas the nitrogen and crude protein content decreased. Specific methane yields decreased considerably from 280 to 119 mL/g VS with a prolonged harvest period, whereas the biomass yield per hectare increased. A maximum dry matter yield of 41.63 t/ha was achieved when the Pennisetum hybrid was harvested in October. When the cutting frequencies increased from twice to three times per year, the specific methane yields increased as the biomass yield decreased. Because of the reverse trend of anaerobic digestion performance...

In this study, we sought to investigate the expression of microRNA (miR)-214 on the osteogenic differentiation of bone marrow‑derived mesenchymal stem cells (BMSCs) and explore the possible underlying mechanisms. We found that the overexpression of miR‑214 effectively promoted the adipocyte differentiation of BMSCs in vitro, reduced alkaline phosphatase (ALP) activity and the gene expression of collagen type I (Col I), osteocalcin (OCN) and osteopontin (OPN) in the BMSCs. We further found that the overexpression of miR‑214 suppressed the protein expression of fibroblast growth factor (FGF), phosphorylated c‑Jun N-terminal kinase (p-JNK) and phosphorylated p38 (p-p38) in the BMSCs. The downregulation of miR‑214 promoted the osteogenic differentiation of BMSCs, and increased ALP activity and Col I, OCN and OPN gene expression in the BMSCs. It also increased FGF p-JNK and p-p38 protein expression in the BMSCs. The use of JNK inhibitor (SP600125) enhanced the inhibitory effects of miR‑214 overexpression on osteogenic differentiation, ALP activity, and Col I, OCN and OPN gene expression in the BMSCs. Lastly, the use of p38 inhibitor (SB202190) also enhanced the inhibitory effects of miR‑214 overexpression on ALP activity, and Col I, OCN and OPN gene expression in the BMSCs. These results provide a mechanism responsible for the suppressive effects of miR‑214 on the osteogenic differentiation of BMSCs involving the inhibition of the JNK and p38 pathways.

Fair share scheduling has been widely used in many distributed systems. Layered Queueing Networks (LQN) are a widely used performance evaluation technique for distributed systems. Therefore, being able to evaluate performance of systems using fair share scheduling is essential. However, Fair share scheduling in a LQN model could only be solved using simulation previously. A main concern of simulation is long execution times. This paper uses a method called ‘Dynamic Parameter substitutions’ (DPS) to solve the Fair share scheduling analytically. DPS is an iterative method to calculate state-based parameters using performance results that are found using Mean Value Analysis (MVA). The paper shows how DPS is integrated into the LQNS solver (LQNS-DPS), which makes solutions of models with fair scheduling both fast and scalable. LQNS-DPS was verified using two sets of models, both with cap and guarantee shares. Over 150 randomly parameterized models, throughput found using LQNS-DPS was on average no worse than 6 % of the result found from simulation.