Microbial consortium and its spatial distribution in a compartmentalized anaerobic reactor.

The compartmentalized anaerobic reactor (CAR) is a patent novel high-rate reactor, which consists of three compartments. The reactor has a great potential for application due to its many advantages. In this work, the microbial consortium, spatial distribution, and their relationship with performance of CAR were investigated by means of polymerase chain reaction, denaturing gradient gel electrophoresis, and fluorescence in situ hybridization. The results showed that the predominant archaea were Methanobacterium, Methanosaeta, and Methanospirillum, and the predominant bacteria were Firmicutes, Deltaproteobacteria, Spirochaetes, Actinobacteria, and Gammaproteobacteria in the microbial consortium. The methanogenic archaea (MA), the hydrogen-producing acetogenic bacteria (HAB), and the hydrolytic fermentative bacteria (HFB) were found to be predominant in the upper, middle, and bottom compartments, respectively. The results revealed that the granular sludge took on a stratified microbial structure. The HFB, HAB, and MA were located in the outer shell, middle layer, and core, respectively. The microbial populations from the bottom compartment were relatively homogeneous in the granular sludge, and from the middle and upper compartments, they were relatively heterogeneous in the granular sludge. The microbial consortia and their spatial distribution were in accordance with the organic loading rate and chemical components in the three compartments.

Anaerobic ferrous oxidation by heterotrophic denitrifying enriched culture.

Heterotrophic denitrifying enriched culture (DEC) from a lab-scale high-rate denitrifying reactor was discovered to perform nitrate-dependent anaerobic ferrous oxidation (NAFO). The DEC was systematically investigated to reveal their denitrification activity, their NAFO activity, and the predominant microbial population. The DEC was capable of heterotrophic denitrification with methanol as the electron donor, and autotrophic denitrification with ferrous salt as the electron donor named NAFO. The conversion ratios of ferrous-Fe and nitrate-N were 87.41 and 98.74 %, and the consumption Fe/N ratio was 2.3:1 (mol/mol). The maximum reaction velocity and half saturation constant of Fe were 412.54 mg/(l h) and 8,276.44 mg/l, and the counterparts of N were 20.87 mg/(l h) and 322.58 mg/l, respectively. The predominant bacteria were Hyphomicrobium, Thauera, and Flavobacterium, and the predominant archaea were Methanomethylovorans, Methanohalophilus, and Methanolobus. The discovery of NAFO by heterotrophic DEC is significant for the development of wastewater treatment and the biogeochemical iron cycle and nitrogen cycle.

[Main hypotheses on mechanisms underlying plant invasion: A review.] / æ¤ç‰©å ¥ä¾µæœºåˆ¶çš„ä¸»è¦å‡è¯´.

Plant invasion is one of the most serious global problems, destroying ecosystem structure and function. With the severity of plant invasion, it is particularly important to understand the mechanisms of plant invasion in order to control and solve the problem. We summarized different mechanisms of plant invasion and the synergy among them, expounded the allelopathy, the plant-soil feedbacks, the reciprocal symbiosis, the effects of plant functional traits and phenotype plasticity in the process of plant invasion, and comprehensively analyzed the synergy of multiple mechanisms on plant invasion trajectory. According to the results, the invasion trajectory of alien plants in the invasive site was divided into four stages: introduction, colonization, establishment, and invasion. Integrating all kinds of obstacles and promoting factors encountered into it and putting forward the invasion curve of plants would contribute to the future research and management of invasive plants. We further highlighted the current research deficiencies and future research directions and objectives based on analyzing current research methods of plant invasion.

Pretreatment Pokemon Level as a Predictor of Response to Cisplatin and Paclitaxel in Patients with Unresectable Non-Small Cell Lung Cancer.

BACKGROUND: We firstly investigated the expression of Pokemon in patients with non-small cell lung cancer (NSCLC), then characterized the role of Pokemon in evaluating the response to combined cisplatin and paclitaxel chemotherapy and prognosis. PATIENTS AND METHODS: In this study, 61 patients with previously untreated locally advanced or metastatic NSCLC were treated with a combination chemotherapy comprising cisplatin and paclitaxel. The correlation between serum expression of Pokemon and effectiveness of chemotherapy was assessed. RESULTS: The expression level of Pokemon in NSCLC patients was higher than that in healthy controls (p = 0.000), and was correlated with tumor size and TNM stage (p < 0.05). Kaplan-Meier analysis and Cox proportional hazard model demonstrated a poor response and shorter survival time in patients with pretreatment Pokemon levels in excess of 135.09 ng/ml compared to those with Pokemon levels below 135.09 ng/ml (p = 0.013). Pokemon ≥ 135.09 ng/ml was an independent risk factor for survival time in NSCLC patients undergoing combination chemotherapy (p = 0.018). CONCLUSION: The serum level of Pokemon correlated with efficacy of cisplatin and paclitaxel combination chemotherapy and survival time, which indicated that Pokemon may be a potentially useful biomarker for predicting treatment effectiveness of first-line chemotherapy and prognosis in NSCLC.

Enhancing Thermal Conductive Performance of Vertically Aligned Carbon Nanotube Array Composite by Pre-Annealing Treatment.

Vertically aligned carbon nanotube (VACNT) array/polymer composite has already been recognized as a promising candidate for advanced thermal pad in thermal management of high-power electronic devices. However, the thermal conductive performance of this composite was limited by the quality of CNTs arrays. In this study, pre-annealing treatment was used to purify CNT arrays and improve thermal conductive performance of VACNT arrays/silicone composite. The thermal conductivity of the composite was enhanced by 34.52% and the thermal interface resistance was also reduced by 65.94% at a pre-annealing temperature of 490 °C for 5 min. The annealing process could remove some amorphous carbon and open the tips of CNTs. As a result, the interfacial compatibility in composite between carbon nanotube and polymer matrix was improved. The cyclic compression and tension performance of VACNT/S160 composite was investigated for further application.

Acute toxicity of pharmaceutical wastewaters containing antibiotics to anaerobic digestion treatment.

In the present study, a method for prediction of the toxicity of pharmaceutical wastewaters containing antibiotics to microbial communities in anaerobic digestion treatment was developed. Luminescent bacterium assay was carried out with Vibrio fischeri as indicator. The individual and joint toxicities of antibiotics and anaerobic digestion metabolites were investigated by using the 15-min half inhibitory concentration (15 min-IC50) at pH 7.00±0.05. The results showed that the 15 min-IC50 of Amoxicillin, Kanamycin, Lincomycin and Ciprofloxacin were 3.99, 5.11, 4.32 and 5.63 g L(-1) respectively, and the toxicity descended in the order of Amoxicillin, Lincomycin, Kanamycin and Ciprofloxacin. Using equitoxic ratio mixing method, the joint toxicities of four anaerobic digestion intermediates, the four intermediates together with Amoxicillin, Ciprofloxacin, Kanamycin or Lincomycin were determined, which displayed that their interactions were additive, additive, synergistic, synergistic and synergistic respectively. Finally the joint effect of all intermediates and antibiotics was synergistic. The method has promising applications in evaluating the joint toxicity of anaerobic digestion intermediates and antibiotics, and has laid the foundations for assessing the feasibility of anaerobic treatment of pharmaceutical wastewater containing antibiotics.

Toxicity assessment of anaerobic digestion intermediates and antibiotics in pharmaceutical wastewater by luminescent bacterium.

In order to evaluate the effect of anaerobic digestion intermediates and antibiotics in pharmaceutical wastewaters on anaerobic digestion process, their acute toxicities were tested using the 15 min median inhibitory concentration (IC(50)) at pH 7.00 ± 0.05. The results showed that the IC(50) of ethanol, acetate, propionate and butyrate were 19.40, 20.71, 10.47 and 12.17 g L(-1) respectively, which suggested the toxicity descended in the order of propionate, butyrate, ethanol and acetate. The IC(50) of aureomycin, polymyxin and chloromycetin were 12.06, 6.24 and 429.90 mg L(-1) respectively, which indicated the toxicity descended in the order of polymyxin, aureomycin and chloromycetin. Using equitoxic ratio mixing method, the joint toxicities of five groups referred by A (four anaerobic digestion intermediates), B (four anaerobic digestion intermediates and aureomycin), C (four anaerobic digestion intermediates and polymyxin), D (four anaerobic digestion intermediates and chloromycetin) and E (four anaerobic digestion intermediates, aureomycin, polymyxin and chloromycetin) were investigated respectively. Their interactions were additive (A), synergistic (B), additive (C), synergistic (D) and synergistic (E). The investigation would lay a basis for the optimization of anaerobic biotechnology for pharmaceutical wastewater treatment.

[Acute toxicity of antibiotics and anaerobic digestion intermediates in pharmaceutical wastewaters].

In order to determine the toxicity of antibiotics and anaerobic digestion intermediates on anaerobic treatment of pharmaceutical wastewaters containing antibiotics, the single and joint toxicities of some antibiotics and intermediates to Photobacterium phosphoreum were tested by using the 15-min half inhibitory concentration (15 min-IC50) at pH = 7.00 +/- 0.05. The results showed that the 15 min-IC50 of ethanol, acetate, propionate and butyrate were 19.40, 20.71, 10.47 and 12.17 g x L(-1), respectively, which indicated that the toxicity descended in the order of propionate, butyrate, ethanol and acetate. The 15 min-IC50 of Amoxicillin, Kanamycin, Lincomycin and Ciprofloxacin were 3.99, 5.11, 4.32 and 5.63 g x L(-1), respectively, so the toxicity descended in the order of Amoxicillin, Lincomycin, Kanamycin and Ciprofloxacin. Using equal effect mixing method, the joint toxicity of four anaerobic digestion intermediates, the four intermediates together with Amoxicillin, Ciprofloxacin, Kanamycin, Lincomycin individually and all together were investigated, which demonstrated that the first three interactions were additive and the last three were synergistic. The observations have laid a foundation for control and optimization of anaerobic biotechnology for pharmaceutical wastewater containing antibiotics.

Hydraulic characteristics and their effects on working performance of compartmentalized anaerobic reactor.

The compartmentalized anaerobic reactor (CAR) is a patent novel high-rate reactor and shows a great potential for its application. The hydraulic characteristics and their effects on the working performance of CAR were investigated. The flow pattern tended to plug flow at normal organic loading rate (OLR) and completely mixed flow at high OLRs. The relation of hydraulic dead space (HDS or V(h)) with hydraulic loading rate (HLR or L) and biogas production rate (BPR or G) was V(h) = 3.75 L + 0.19 G-9.47. The hydraulic efficiency of CAR was good or near to good. Both HLR and BPR had significant effects on the hydraulic efficiency, but their effect became less at super-high OLR. They also had a slight influence on the effective volume ratios of CAR, but the influence of BPR almost disappeared at super-high OLR. The good working performance of CAR was ascribed to the improved reactor configuration.