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Dongxue Yin Wei Liu Ningning Zhai Yongzhong Feng Gaihe Yang Xiaojiao Wang Xinhui Han 《PloS one》2015,10(5)
This study investigated the effect of sunlight-dark conditions on volatile fatty acids (VFAs), total ammonium nitrogen (TAN), total alkalinity (TA) and pH during pig manure (PM) digestion and then the subsequent influence on biogas yield of PM. PM1 and PM2 were performed in a transparent reactor and a non-transparent reactor, respectively. Two sets of experiments were conducted with a temperature of 35.0±2.0 °C and a total solid concentration of 8.0% to the digestion material. The dynamic change of the four parameters in response to sunlight-dark conditions resulted in variations of the physiological properties in the digester and affected the cumulative biogas production (CBP). PM1 obtained higher CBP (15020.0 mL) with a more stable pH and a lower TAN concentration (1414.5 mg/L) compared to PM2 (2675.0 mL and 1670.0 mg/L, respectively). The direct path coefficients and indirect path coefficients between the four parameters and CBP were also analyzed. 相似文献
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Chun Wang Derrick Y. F. Lai Chuan Tong Weiqi Wang Jiafang Huang Chongsheng Zeng 《PloS one》2015,10(5)
Understanding the functional relationship between greenhouse gas fluxes and environmental variables is crucial for predicting the impacts of wetlands on future climate change in response to various perturbations. We examined the relationships between methane (CH4) emission and temperature in two marsh stands dominated by the Phragmites australis and Cyperus malaccensis, respectively, in a subtropical estuarine wetland in southeast China based on three years of measurement data (2007–2009). We found that the Q10 coefficient of CH4 emission to soil temperature (Qs10) from the two marsh stands varied slightly over the three years (P > 0.05), with a mean value of 3.38 ± 0.46 and 3.89 ± 0.41 for the P. australis and C. malaccensis stands, respectively. On the other hand, the three-year mean Qa10 values (Q10 coefficients of CH4 emission to air temperature) were 3.39 ± 0.59 and 4.68 ± 1.10 for the P. australis and C. malaccensis stands, respectively, with a significantly higher Qa10 value for the C. malaccensis stand in 2008 (P < 0.05). The seasonal variations of Q10 (Qs10 and Qa10) differed among years, with generally higher values in the cold months than those in the warm months in 2007 and 2009. We found that the Qs10 values of both stands were negatively correlated with soil conductivity, but did not obtain any conclusive results about the difference in Q10 of CH4 emission between the two tidal stages (before flooding and after ebbing). There were no significant differences in both Qs10 and Qa10 values of CH4 emission between the P. australis stand and the C. malaccensis stands (P > 0.05). Our results show that the Q10 values of CH4 emission in this estuarine marsh are highly variable across space and time. Given that the overall CH4 flux is governed by a suite of environmental factors, the Q10 values derived from field measurements should only be considered as a semi-empirical parameter for simulating CH4 emissions. 相似文献
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Wang F Liu P Zhang Q Zhu J Chen T Arimura SI Tsutsumi N Lin J 《The Plant journal : for cell and molecular biology》2012,72(1):43-56
The balance between mitochondrial fission and fusion is disrupted during mitosis, but the mechanism governing this phenomenon in plant cells remains enigmatic. Here, we used mitochondrial matrix‐localized Kaede protein (mt‐Kaede) to analyze the dynamics of mitochondrial fission in BY‐2 suspension cells. Analysis of the photoactivatable fluorescence of mt‐Kaede suggested that the fission process is dominant during mitosis. This finding was confirmed by an electron microscopic analysis of the size distribution of mitochondria in BY‐2 suspension cells at various stages. Cellular proteins interacting with Myc‐tagged dynamin‐related protein 3A/3B (AtDRP3A and AtDRP3B) were immunoprecipitated with anti‐Myc antibody‐conjugated beads and subsequently identified by microcapillary liquid chromatography–quadrupole time‐of‐flight mass spectrometry (CapLC Q‐TOF) MS/MS. The identified proteins were broadly associated with cytoskeletal (microtubular), phosphorylation, or ubiquitination functions. Mitotic phosphorylation of AtDRP3A/AtDRP3B and mitochondrial fission at metaphase were inhibited by treatment of the cells with a CdkB/cyclin B inhibitor or a serine/threonine protein kinase inhibitor. The fate of AtDRP3A/3B during the cell cycle was followed by time‐lapse imaging of the fluorescence of Dendra2‐tagged AtDRP3A/3B after green‐to‐red photoconversion; this experiment showed that AtDRP3A/3B is partially degraded during interphase. Additionally, we found that microtubules are involved in mitochondrial fission during mitosis, and that mitochondria movement to daughter cell was limited as early as metaphase. Taken together, these findings suggest that mitotic phosphorylation of AtDRP3A/3B promotes mitochondrial fission during plant cell mitosis, and that AtDRP3A/3B is partially degraded at interphase, providing mechanistic insight into the mitochondrial morphological changes associated with cell‐cycle transitions in BY‐2 suspension cells. 相似文献
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