Effects of continuous low-speed biogas agitation on anaerobic digestion of high-solids pig manure: Performance and microbial community.

This study aimed to investigate effects of continuous low-speed biogas agitation on the anaerobic digestion (AD) performance and microbial community of high-solids pig manure (total solids content of 10%). Our results reveal that at a biogas agitation intensity of 1.10 L/g feed VS/d, CH4 production increased by 16.67% compared to the non-agitated condition, the removal efficiency of H2S reached 63.18%, and the abundance of Methanosarcina was the highest. The presence of Hungateiclostridiaceae was associated with H2S concentrations. An increasing biogas agitation intensity led to an elevated pH and a decreased oxidation-reduction potential (ORP). Acetate concentrations, pH, and ORP values indicated changes in H2S concentrations. Sedimentibacter demonstrates the potential to indicate biogas agitation intensity and pH. We demonstrate that continuous low-speed biogas agitation effectively increases CH4 production and reduces H2S concentrations in AD of high-solids pig manure, offering a potential technical pathway for developing AD processes for high-solids pig manure, it also demonstrates that AD process can reduce the risk of pathogen and parasite transmission.

Up-flow anaerobic sludge blanket treatment of swine wastewater: Effect of heterologous and homologous inocula on anaerobic digestion performance and the microbial community.

The effects of heterogenous (anaerobic sludge from treating distillery sewage, ASDS) and homologous (anaerobic sludge from treating swine wastewater, ASSW) inocula on anaerobic digestion and the microbial community in an up-flow anaerobic sludge blanket treating swine wastewater were compared. The highest chemical oxygen demand removal efficiencies with ASDS (84.8%) and ASSW (83.1%) were obtained with an organic loading rate of 15 kg COD/m3/d. For ASSW compared with ASDS, methane production efficiency was 15.3% higher and excess sludge production was 73.0% lower. The abundance of the cellulose hydrolyzing bacterium Clostridium sensu stricto_1 with ASDS (36.1%) was 1.5 times that with ASSW, while that of Methanosarcina with ASSW (22.9%) was > 100 times that with ASDS. ASDS reduced the content of pathogenic bacteria by 88.0%, while ASSW maintained a low level of pathogenic bacteria. ASSW greatly improved the methane production efficiency of wastewater and is more suitable for treating swine wastewater.

Low-Cost, Unsinkable, and Highly Efficient Solar Evaporators Based on Coating MWCNTs on Nonwovens with Unidirectional Water-Transfer.

Solar vapor generation technology is promising in seawater desalination, sewage purification, and other fields. However, wide application of this technology is still largely confined due to its high cost and difficulties for scalable production. In this study, an ever-floating solar evaporator is fabricated by coating multiwall carbon nanotubes on a bicomponent nonwoven composed of polypropylene/polyethylene core-sheath fibers. This all-fiber structure is highly porous and ultralight, with large specific area (for efficient water evaporation), interconnected channels (for easy vapor escape), and low thermal conductivity (to avoid heat loss). The unique unidirectional water-transfer behavior of the nonwoven enables it to spontaneously pump an adjustable amount of water for interfacial solar heating and a delicate balance between water supply and loss may accelerate the evaporation speed of water. These distinct benefits endow the solar evaporator with excellent evaporation rates of 1.44 kg m-2  h-1 under the simulated irradiation of 1 sun and 12.81 kg m-2  d-1 under natural sunlight. Moreover, the evaporator can be fabricated by using low-cost materials and industrialized methods (overall cost ≈2.4 USD m-2 ), making one believe its practical significance for commercial solar steam evaporation.

Novel insights of impacts of solid content on high solid anaerobic digestion of cow manure: Kinetics and microbial community dynamics.

High solid anaerobic digestion has become the mainstream technology for sustainable on-farm treatment of solid wastes but has not been optimized with respect to increasing solid content in cow manure (CM). In the present study, CM was batch digested at total solid (TS) of 5%, 10%, 15% and 20% and microbial communities were investigated. The process remained stable up to 15% TS. The biomethane production rate at TS of 10% and 15% was reported to be 352.2 mL g-1 VS and 318.6 mL g-1 VS, reaching up to 83% and 75% of TS 5% biomethane, respectively. Kinetics results disclosed that the biodegradable organics could be utilized at increasing solid content with decreasing hydrolysis rate. The abundances of hydrogenotrophic and methylotrophic methanogens increased significantly with increasing solid content. This study is of great importance for understanding and application of high solid anaerobic digestion of cow manure.

Manufacturing of polytetrafluoroethylene fine fibers by waterjet impacting.

Due to unique anti-erosion properties and excellent thermal stability, polytetrafluoroethylene (PTFE) fibers are regarded as an ideal material to manufacture filters for industrial dust purification. Based on weak interactions between PTFE molecular chains, we applied a high-pressure waterjet to cause normal PTFE split-film fibers to split fibers again. Four kinds of PTFE split-film fibers and sintered films with different molecular weights were produced. Afterward, waterjets were introduced to impact PTFE sintered films and split-film fibers under different pressures and jets, and we analyzed variations in the sintered film morphology and fiber diameter. When the molecular weight was increased, the visible light transmittance of four different PTFE sintered films at the wavelength of 382 nm decreased from 85.7% to 77.6% and then increased to 95.1%, which was consistent with light-dark characteristics in light micrographs of sintered films. The four PTFE sintered films split into fibers under the waterjet impact force. In particular, MW49 PTFE sintered film was split into microscale fibers using waterjets at 110 bar and 5 jets. Finally, waterjets were applied to impact normal PTFE split-film fibers to force the original fibers to split into fine fibers. Different PTFE split-film fibers exhibited a significant decrease in the average diameter. In particular, in the case of MW49 PTFE split-film fibers, the average diameter of fibers impacted by 5 jets at 110 bar decreased from 27.4 to 15.7 µm, confirming the suitability of high-pressure waterjets for the splitting of PTFE split-film fibers into microscale fibers.

Characteristics and mechanisms of H2S production in anaerobic digestion of food waste.

The biogas produced in food waste anaerobic digestion (FWAD) contains H2S which can lead to corrosion, bad smell and poisoning accident. To control H2S pollution, the characteristics and mechanisms of H2S production in FWAD should be known. In this study, a lab-scale FWAD batch test was applied for 20 days under 35 °C. The production potential and average concentration of H2S were 765 ± 163 g/t (TS) and 1065 ± 267 ppm, respectively. 76% of total H2S was produced within 6 h on the first day of fermentation, acidification and gas production were key reasons for high H2S production at this time. Compared to H2S peak production time, that of methane was long (4 days) and after that of H2S. Sulfides were found to be the dominant form of sulfur (accounting for 20-70% of total sulfur) in the mixed fermentation liquor in fermentation batch. These sulfides were from protein, which could be decomposed slowly to sulfide by protein-using bacteria and methanogen at the time of methane production peak, and sulfate, which could be converted to sulfide by Sulfate reducing bacteria (SRB) during the first two days of fermentation. Protein would be the main contributor to sulfide/H2S for the continuous feeding FWAD system in long term operation, due to its presence as the main form of sulfur in food waste.

Autophagy inhibition of cancer stem cells promotes the efficacy of cisplatin against non-small cell lung carcinoma.

BACKGROUND: Clinical treatment of non-small cell lung carcinoma (NSCLC) by cisplatin eventually results in drug resistance, which cancer stem cells and autophagy are believed to be involved in. In the present study, we aimed to explore the effect of autophagy-inhibited cancer stem cells in NSCLC. METHODS: Cancer stem cells were identified by CD133 expression levels detected by immunochemistry, real-time polymerase chain reaction, western blot, and flow cytometry. Stemness was detected by sphere-forming assays of tumor cells. Autophagy was determined by LC3-II expression at mRNA and protein levels. The effect of chloroquine (CQ) on autophagy was detected by real-time polymerase chain reaction, western blot and sphere-forming assay in vitro, and tumor growth in male NOD/SCID mice. RESULTS: Cisplatin (CDDP) treatment enhanced CD133+ cell ratios in clinical NSCLC specimens and NSCLC cell line A549. The CD133+ cells enriched by CDDP exhibited higher autophagy levels. Autophagy inhibition by CQ inhibited CD133+ stemness and promoted CDDP efficiency in A549 cells. In addition, the combination of CDDP and CQ treatment significantly inhibited autophagy levels and cancer stem cell proportions in vitro, and dramatically suppressed tumor growth compared with individual agents. CONCLUSION: Autophagy inhibition of cancer stem cells could promote the efficacy of cisplatin against NSCLC.

A strategy based on gas chromatography-mass spectrometry and virtual molecular docking for analysis and prediction of bioactive composition in natural product essential oil.

The discovery of leads from medicinal plants is crucial to drug development. The present study presents a strategy based on GC-MS coupled with molecular docking for analysis, identification and prediction of protein tyrosine phosphatase 1B inhibitors in the essential oil from Himalayan Cedar (HC). The essential oil with IC50 value of 120.71±0.26µg/mL exhibited potential activity against protein tyrosine phosphatase 1B (PTP1B) in vitro. After GC-MS analysis, 35 compounds were identified from this oil. The identified compounds were individually docked with PTP1B. Caryophyllene oxide with the lowest binding energy of -6.28kcal/mol was completely wrapped by the active site of PTP1B. The docking results indicated that caryophyllene oxide has potential PTP1B inhibitory activity and may be responsible for the PTP1B inhibitory activity of the essential oil. Caryophyllene oxide in the essential oil of Himalayan Cedar was isolated by HSCCC and the PTP1B inhibitory activity of this compound was then evaluated; the IC50 value was 31.32±0.38µM. The result revealed that the present strategy can effectively discover the active composition from the complex mixture of medicinal plants.

Spatiotemporal dynamics of bacterial and archaeal communities in household biogas digesters from tropical and subtropical regions of Yunnan Province, China.

A combination of 16S rRNA gene PCR-based techniques and the determination of abiotic factors were used to study community composition, richness, and evenness and the correlation between biotic and abiotic factors in 19 household biogas digesters in tropical and subtropical regions of Yunnan Province, China. The results revealed that both bacterial and archaeal community composition differed between regions and archaeal community composition was more affected by season than bacterial; regardless of sampling location, the dominant bacterial phyla included Chloroflexi, Bacteroidetes, Firmicutes, and Proteobacteria, and the most dominant archaeal phylum was Euryarchaeota; in digesters from both regions, Chloroflexi as the first or second most dominant bacteria accounted for 21.50-26.10 % of bacterial library sequences, and the phylum Crenarchaeota as the second most dominant archaea accounted for 17.65-19.77 % of archaeal library sequences; the species Methanosaeta concilii as the most dominant archaeal species accounted for 67.80-72.80 % of the sequences. This study found that most of the abundant microbial communities in 19 biogas digesters are similar, and this result will provide enlightenment for finding the universal nature in rural biogas digesters at tropical and subtropical regions in China.

Investigation of methanogenic community structures in rural biogas digesters from different climatic regions in Yunnan, southwest China.

Understanding of the microbial community structures of the biogas digesters in different climatic regions can help improve the methane production in the fermentation process. The methanogenic archaeal diversity in four rural biogas digesters (BNA, JSA, LJA, and XGA) was investigated by a culture-independent rRNA approach in different climatic regions in Yunnan. Community structure composed of 711 clones in the all libraries. A total of 33 operational taxonomic units (OTUs) were detected, and major groups of methanogens were the orders Methanosarcinales and Methanomicrobiales. 63.2 % of all archaeal OTUs belong to the order Methanosarcinales which mostly contain acetotrophic methanogens. Methanomicrobiales (19.5 % in all OTUs) were detected in considerable number. Additionally, there were minor rates of uncultured archaea. The principal component analysis indicated that the genus Methanosaeta was mainly affected by the fermentation temperatures.

Weight loss during radiotherapy for nasopharyngeal carcinoma: a prospective study from northern China.

The objective of this explorative study was to measure weight loss during radiotherapy and to select predictive factors for early identification of malnourished patients. One hundred and fifty-nine consecutive initial diagnosed nasopharyngeal carcinoma patients attending the Oncology Center at Qilu Hospital of Shandong University, China participated. Patients' weights were measured at the baseline visit and at the end of radiotherapy. The baseline characteristics were recorded. A stepwise linear regression analysis was performed to find association between baseline characteristics and malnutrition. At baseline, 56% of the patients already had a 5% weight loss during the last 3 mo; after the treatment, the median weight loss was 6.9 kg (range, 2.1-12.6 kg). After the multivariate linear regression analyses, the following factors turned out to be independent prognostic factors for significant weight loss: global quality of life, body mass index, N stage, insomnia, radiation techniques, Karnofsky performance status, concurrent chemotherapy, and fatigue. The authors conclude that severe weight loss during radiotherapy for nasopharyngeal carcinoma is common. A combination of clinical factors may lead to malnutrition for nasopharyngeal carcinoma during radiotherapy.