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151.
An experimental study on biomass air-steam gasification in a fluidized bed   总被引:14,自引:0,他引:14  
The characteristics of biomass air-steam gasification in a fluidized bed are studied in this paper. A series of experiments have been performed to investigate the effects of reactor temperature, steam to biomass ratio (S/B), equivalence ratio (ER) and biomass particle size on gas composition, gas yield, steam decomposition, low heating value (LHV) and carbon conversion efficiency. Over the ranges of the experimental conditions used, the fuel gas yield varied between 1.43 and 2.57 Nm3/kg biomass and the LHV of the fuel gas was between 6741 and 9143 kJ/Nm3. The results showed that higher temperature contributed to more hydrogen production, but too high a temperature lowered gas heating value. The LHV of fuel gas decreased with ER. Compared with biomass air gasification, the introduction of steam improved gas quality. However, excessive steam would lower gasification temperature and so degrade fuel gas quality. It was also shown that a smaller particle was more favorable for higher gas LHV and yield.  相似文献   
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Xu A  Yao J  Yu L  Lv S  Wang J  Yan B  Yu Z 《Journal of applied microbiology》2004,96(6):1317-1323
AIM: To increase the transformation rate of l-sorbose to 2-keto-l-gulonic (2-KLG) acid in a two-step process of l-ascrobic acid manufacture by ion beam. METHODS AND RESULTS: Gluconobacter oxydans (GO29) and Bacillus megaterium (BM80) were used in the present study. Ion implantation was carried out with the heavy ion implantation facility at the institute of Plasma Physics in China. 2-KLG in whole culture broth was determined by iodometry. Mutants were screened by single-colony isolation and 2-KLG accumulation in broth. GO29 and BM80 were implanted by either hydrogen ions (H(+)) or nitrogen ions (N(+)) with various doses, respectively. The average transformation rate of GM112-302 bred by ion beam in Gram-molecule was increased from 79.3 to 94.5% after eight passages in shaking flasks. Furthermore, in 180-ton fermentors in Jiangsu Jiangshan Pharmaceutical Co. Ltd, the transformation rate was stable at 92.0%, indicating a producer could get 0.99 kg of gulonic acid from 1.0 kg of sorbose. CONCLUSION: Ion beam as a new mutation source had potential advantages in breeding. Comparing with original mixture GO29 and BM80, GM112-302 is more efficient in accumulating 2-KLG, especially at the later phase. SIGNIFICANCE AND IMPACT OF THE STUDY: GM112-302 bred by ion beam implantation dramatically increased the transformation rate by 19.2%, which greatly increased efficiency and reduced the cost of l-ascorbic acid manufacture in a two-step process.  相似文献   
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TRB3 interacts with CtIP and is overexpressed in certain cancers   总被引:2,自引:0,他引:2  
Xu J  Lv S  Qin Y  Shu F  Xu Y  Chen J  Xu BE  Sun X  Wu J 《Biochimica et biophysica acta》2007,1770(2):273-278
TRB3, a human homolog of Drosophila Tribbles, has been recently shown as a critical negative regulator of Akt and S6 kinase activation in a number of cellular processes. Here we found that TRB3 interacted with an important cell cycle regulator CtIP (CtBP-interacting protein) and the interaction involved the C-terminus of both proteins. Interestingly, TRB3 and CtIP co-localized to the nucleus in HeLa cells and exhibited a unique dot-like pattern. Finally, we demonstrated that TRB3 was overexpressed in multiple tumor tissues. Since CtIP plays important roles in cell cycle checkpoint control and it has been implicated in tumorigenesis, our data suggest that TRB3 may be involved in these biological processes through interacting with CtIP.  相似文献   
156.
Retroperitoneal liposarcoma (RLPS) is the most common subtype of retroperitoneal soft tissue sarcoma, characterized by a high recurrence rate and insensitivity to radiotherapy and chemotherapy. The function of tumor microenvironmental components, especially tumor-associated fibroblasts (TAFs), remains unclear in RLPS. The crosstalk between tumor cells and stromal cells should be clarified for therapy target discovery in RLPS. In this study, we demonstrated that TAFs from dedifferentiated liposarcoma (DDLPS) could attract LPS cells and promote their proliferation and migration. However, although α-SMA is positively expressed in RLPS, its expression does not indicate prognosis. By screening differentially expressed genes, performing Oncomine visualization, TCGA gene expression correlation analysis and qPCR verification, we determined that thrombospondin-2 (THBS2) gene expression was related to TAFs. The expression of Tsp2 protein, which was encoded by THBS2, was correlated with α-SMA expression, and it was an independent predictive factor for disease-free survival and recurrence-free survival in patients with RLPS. In vitro, Tsp2 facilitated the transformation of bone marrow-derived fibroblasts (BMFs) to TAFs and promoted the malignant biological behaviors of LPS cells by activating the MAPK/MEK/ERK pathway. Therefore, suppression of Tsp2 is expected to be a promising treatment method for RLPS patients.  相似文献   
157.
Phage P2 was isolated from failed fermentation broth carried out by Lactiplantibacillus plantarum IMAU10120. A previous study in our laboratory showed that this phage belonged to the Siphoviridae family. In this study, this phage’s genomic characteristics were analyzed using whole-genome sequencing. It was revealed that phage P2 was 77.9 kb in length and had 39.28% G + C content. Its genome included 96 coding sequences (CDS) and two tRNA genes involved in the function of the structure, DNA replication, packaging, and regulation. Phage P2 had higher host specificity; many tested strains were not infected. Cell wall adsorption experiments showed that the adsorption receptor component of phage P2 might be a part of the cell wall peptidoglycan. This research might enrich the knowledge about genomic information of lactobacillus phages and provide some primary data to establish phage control measures.  相似文献   
158.
For future interplanetary manned spaceflight, mental issues, as well as physiological problems, must inevitably be considered and solved. Mars500 is a high-fidelity ground simulation experiment that involved 520 days of confined isolation for six multinational crewmembers. This experiment provided a good opportunity to perform psycho-physiological and psycho-social researches on such missions. To investigate emotional responses and psychological adaptation over long-term confinement, the International Affective Pictures System (IAPS) was selected as the visual emotional stimuli in this study. Additional data collected and analyzed included the Profile of Mood States (POMS) questionnaire and the levels of four types of plasma hormones: cortisol, 5-hydroxy tryptamine, dopamine, and norepinephrine. The results demonstrated an obvious bias on valence rating for unpleasant stimuli with time (p<0.05), and the correlation between psychological and biochemical data was identified (p<0.05). Overall, we concluded that the confined crew tended to assign positive ratings to negative pictures with time, which might be driven by a defensive system. There was a stage-changing pattern of psychological adaptation of the Mars500 crew, which is similar to the third-quarter phenomenon.  相似文献   
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Journal of Physiology and Biochemistry - Cardiovascular disease (CVD) is one of the vital causes of morbidity and mortality, and the number of deaths from CVD has increased worldwide. Circular RNAs...  相似文献   
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