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11.
Jingting Zhang Wei Ren Pingli An Zhihua Pan Liwei Wang Zhiqiang Dong Di He Jia Yang Shufen Pan Hanqin Tian 《PloS one》2015,10(9)
It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983–1999 and 2000–2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6–11.0% and 19.5–92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming. 相似文献
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The production task queue has a great significance for manufacturing resource allocation and scheduling decision. Man-made qualitative queue optimization method has a poor effect and makes the application difficult. A production task queue optimization method is proposed based on multi-attribute evaluation. According to the task attributes, the hierarchical multi-attribute model is established and the indicator quantization methods are given. To calculate the objective indicator weight, criteria importance through intercriteria correlation (CRITIC) is selected from three usual methods. To calculate the subjective indicator weight, BP neural network is used to determine the judge importance degree, and then the trapezoid fuzzy scale-rough AHP considering the judge importance degree is put forward. The balanced weight, which integrates the objective weight and the subjective weight, is calculated base on multi-weight contribution balance model. The technique for order preference by similarity to an ideal solution (TOPSIS) improved by replacing Euclidean distance with relative entropy distance is used to sequence the tasks and optimize the queue by the weighted indicator value. A case study is given to illustrate its correctness and feasibility. 相似文献
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Mario Stampanoni Bassi Tommaso Nuzzo Luana Gilio Mattia Miroballo Alessia Casamassa Fabio Buttari Paolo Bellantonio Roberta Fantozzi Giovanni Galifi Roberto Furlan Annamaria Finardi Arianna De Rosa Anna Di Maio Francesco Errico Diego Centonze Alessandro Usiello 《Journal of neurochemistry》2021,159(5):857-866
15.
Energy metabolism and lipid peroxidation of human erythrocytes as a function of increased oxidative stress. 总被引:5,自引:0,他引:5
B Tavazzi D Di Pierro A M Amorini G Fazzina M Tuttobene B Giardina G Lazzarino 《European journal of biochemistry》2000,267(3):684-689
To study the influence of oxidative stress on energy metabolism and lipid peroxidation in erythrocytes, cells were incubated with increasing concentrations (0.5-10 mM) of hydrogen peroxide for 1 h at 37 degrees C and the main substances of energy metabolism (ATP, AMP, GTP and IMP) and one index of lipid peroxidation (malondialdehyde) were determined by HPLC on cell extracts. Using the same incubation conditions, the activity of AMP-deaminase was also determined. Under nonhaemolysing conditions (at up to 4 mM H2O2), oxidative stress produced, starting from 1 mM H2O2, progressive ATP depletion and a net decrease in the intracellular sum of adenine nucleotides (ATP + ADP + AMP), which were not paralleled by AMP formation. Concomitantly, the IMP level increased by up to 20-fold with respect to the value determined in control erythrocytes, when cells were challenged with the highest nonhaemolysing H2O2 concentration (4 mM). Efflux of inosine, hypoxanthine, xanthine and uric acid towards the extracellular medium was observed. The metabolic imbalance of erythrocytes following oxidative stress was due to a dramatic and unexpected activation of AMP-deaminase (a twofold increase of activity with respect to controls) that was already evident at the lowest dose of H2O2 used; this enzymatic activity increased with increasing H2O2 in the medium, and reached its maximum at 4 mM H2O2-treated erythrocytes (10-fold higher activity than controls). Generation of malondialdehyde was strictly related to the dose of H2O2, being detectable at the lowest H2O2 concentration and increasing without appreciable haemolysis up to 4 mM H2O2. Besides demonstrating a close relationship between lipid peroxidation and haemolysis, these data suggest that glycolytic enzymes are moderately affected by oxygen radical action and strongly indicate, in the change of AMP-deaminase activity, a highly sensitive enzymatic site responsible for a profound modification of erythrocyte energy metabolism during oxidative stress. 相似文献
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Allatotropic activity is found in methanolic extracts of the brain–suboesophageal ganglion (SOG)–corpora cardiaca (CC) complex from virgin males of Mythimna loreyi Duponchel (Lepidoptera, Noctuidae). Corpora allata (CA) from 6‐day‐old virgin males exhibit low rates of release of Juvenile Hormone (JH) acid (JHA) in vitro. Release of JHA can be activated by the addition of an extract of brain–SOG–CC complex in a dose‐dependent manner, and this allatotropic activation can be sustained consistently in the continuous presence of such extracts. Based on its trypsin sensitivity and heat stability, the allatotropic factor is most likely a peptide. The allatotropic activity is dependent on the concentration of calcium ions in the medium, with the highest activation achieved beyond 2 m m . The results of nerve transection experiments suggest that both nervi corporis allati I (NCA I) and NCA II are involved in mediating the allatotropic control of CA in vitro. Isolated CA alone show significantly higher rates of release of JHA than the intact brain–SOG–CC–CA complex during the first 3 h of incubation, but the release of JHA reaches almost the same range in both groups by the end of the fourth hour of incubation. 相似文献
18.
Timmers LF Ducati RG Sánchez-Quitian ZA Basso LA Santos DS de Azevedo WF 《Journal of molecular modeling》2012,18(2):467-479
Cytidine Deaminase (CD) is an evolutionarily conserved enzyme that participates in the pyrimidine salvage pathway recycling cytidine and deoxycytidine
into uridine and deoxyuridine, respectively. Here, our goal is to apply computational techniques in the pursuit of potential
inhibitors of Mycobacterium tuberculosis CD (MtCDA) enzyme activity. Molecular docking simulation was applied to find the possible hit compounds. Molecular dynamics simulations
were also carried out to investigate the physically relevant motions involved in the protein-ligand recognition process, aiming
at providing estimates for free energy of binding. The proposed approach was capable of identifying a potential inhibitor,
which was experimentally confirmed by IC50 evaluation. Our findings open up the possibility to extend this protocol to different databases in order to find new potential
inhibitors for promising targets based on a rational drug design process. 相似文献
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