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Species of the order Crocodylia are mostly large, predatory and semi-aquatic reptiles. Crocodylia, the closest living relatives of birds, first appeared in the Late Cretaceous period. In the present study, the complete mitochondrial (mt) genomes of 19 Crocodylia species, including two species (Melanosuchus niger and Caiman yacare) that have not been previously sequenced for mitogenomes, were processed through Illumina sequencing to offer genetic resources and compare with the mitogenomes of Crocodylia species reported previously. In addition, a high-resolution phylogenetic tree of nearly all current recognized species of Crocodylia is constructed based on mitogenomic data. Phylogenetic analyses support monophyly of three families: Alligatoridae (four genera: Alligator , Caiman , Melanosuchus and Paleosuchus), Crocodylidae (three genera: Crocodylus , Mecistops and Osteolaemus) and Gavialidae (two genera: Gavialis and Tomistoma). The tree topology is generally similar to previous studies. Molecular dating suggests that the first split within Crocodylia date back to the Upper Cretaceous (approx. 86.75 Mya). The estimated time to the most recent common ancestor (TMRCA) of Alligatoridae is 53.33 Mya and that of Crocodylidae and Gavialidae is 50.13 Mya, which might be closely linked to climate changes during the Late Palaeocene and Early Eocene. Additionally, this study proves that the diversification rate within Crocodylia began to increase from the Late Eocene (about 36 Mya) and two diversification peak periods of Crocodylia (0–10 Mya and 10–20 Mya) are disclosed, which is roughly consistent with the estimated crocodylian species richness through time. Combining all these clues, we can suggest that climate fluctuation may have played a decisive role in the speciation of Crocodylia. [ABSTRACT FROM AUTHOR]

In order to alleviate chilling injury of soybean seedling in northeast spring soybean production area, effect of exogenous melatonin (MT) on chilling tolerance of soybean under low temperature stress was studied. The object was to find out appropriate MT concentration to improve chilling tolerance of soybean. Cultivar Suinong 26 was used and planted in pots. At V1 stage (one leaf stage of soybean), leaves were sprayed with different concentrations of MT (0, 50, 100, 200 μmol·L-1) for 3 days, then moved to artificialclimate box for 5 days under low temperature (4°C). The effects of MT on photosynthetic characteristics, active oxygen metabolism and osmoregulation of soybeans under 4°C showed that different concentrations of MT enhanced the photosynthesis. Pn, Gs, Tr and photosynthetic pigment increased significantly. Chl a/b decreased significantly with the MT concentrations. The activity of SOD (superoxide dismutase), POD (peroxidase), CAT (catalase), APX (ascorbate peroxidase), Pro (proline) content and root-shoot ratio in leaves exposed to MT increased significantly, reaching a significant difference at concentration of 100 μmol·L-1. While MDA (malondialdehyde) content and the relative conductivity of leaves decreased significantly. The results indicated that exogenous melatonin could alleviate stress injury and improve cold tolerance of soybean seedlings at V1 stage by increasing photosynthetic rate, antioxidant enzyme activity, and reducing membrane lipid peroxidation and regulating osmotic substances. [ABSTRACT FROM AUTHOR]

Pressure enhanced coagulation and sedimentation technique is an effective way for blue algae treatment. It is not clear whether Cyanobacteria balloon rupture will cause Cyanobacteria cells rupture, resulting in high intracellular concentrations of microcystin LR leak into the water, affecting drinking water safety. Therefore, in this study experimental comparative study of pressure and pre-oxidation of water containing Cyanobacteria was carried out to examine the microcystin LR concentration changes and Cyanobacteria removal efficiency. The results showed that microcystin concentration increase was not significant by the pre-treatment with Cyanobacteria water pressure, while the pre-oxidation process caused a significant increase in the concentration of microcystin. After 0.5-0.8 MPa pressure coagulation and sedimentation, removal of Cyanobacteria basically was over 90%, up to 93.5%, while the removal rate by pre-oxidation was low and unstable. Effluent turbidity is also significantly better in the pre-pressure method than the pre-oxidation. The results indicated that pressure enhanced coagulation is a safe and reliable method for Cyanobacteria removal.

In order to ascertain the volumetric change of gas vesicles in cyanobacteria and the floating characteristics, capillary pressure method and image analysis method were used to study burst situation and remanent volume fraction of gas vesicles in cyanobacteria under different pressures. The reform situation after pressuring was also analyzed in this research. The results showed that the volume fraction of gas vesicles in Taihu Lake were 29.52%, 5.73%, 4.43%, 2.71%, 2.46%, 2.19% under 0 MPa, 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.7 MPa determined by the image analysis, and were 10.93%, 1.14%, 0.90%, 0.27%, 0.14%, 0.04% determined by the capillary pressure method; cyanobacteria sank due to the gas vesicles' bursting when the pressure was greater than 0.4 MPa. Gas vesicles and structure after pressure were reformed with the lapse of time, under 1 000 lx, 25 degrees C, after 8 h, 24 h, 48 h, the reformed gas vesicles accounted for 31.02%, 45.68%, 81.05% of total gas vesicles before pressuring. Image analysis method is more accurate in the determination for cyanobacteria gas vesicles' volume, while the volume is smaller measured by traditional capillary pressure method.

The aim of the study was to explore whether the pre-pressure and coagulation sedimentation process would result in algal cell disruption, leading to increased dissolved organic carbon (DOC) in water, based on which, the pressure application mode would be optimized and safe and efficient pre-pressure algae removal process would be obtained. The changes in DOC during the process of pre-pressure and preoxidation treatment, the distribution of molecular weight in water as well as the removal efficiency of algae, turbidity and DOC after coagulation and sedimentation were investigated. The results showed that the DOC in water did not increase but decreased, and the molecular weight decreased after treated with 0.5-0.8 MPa pressure. While KMnO4 and NaClO pre-oxidation both increased the DOC, in the meanwhile, the distribution of molecular weight showed no obvious change. After the pre-pressure coagulation and sedimentation process, the removal rate of algae was 96.23% and that of DOC was 29. 11%, which was by 10% - 30% higher than the rate of pre-oxidation coagulation and sedimentation process.

Objective: To evaluate the efficacy and safety of Mahuang Zhisou Capsule (MHZSC), a compound traditional Chinese herbal medicine, in treatment of acute upper respiratory tract infection of wind-cold syndrome., Methods: A multi-center, double-blind, double dummy, randomized controlled trial was conducted. A total of 240 patients were randomized into treatment group (120 cases, treated with MHZSC) and control group (120 cases, treated with Mahuang Zhisou Pill). The therapeutic course was 3 days., Results: Seven cases were excluded and three cases lost to follow-up. Two hundred and thirty-three cases entered intention-to-treat (ITT) analysis and 230 cases fitted in per-protocol population set (PPS) analysis. After treatment, the therapeutic effect of upper respiratory tract infection was calculated by ITT and PPS analysis respectively. The significant response rate and total response rate in the treatment group were 78.07% and 98.25% (ITT and PPS), while the significant response rates in the control group were 70.59% (ITT) and 70.69%(PPS), and the total response rates were 95.80% (ITT) and 95.69% (PPS) respectively. There were no significant differences in clinical efficacy between the two groups (P>0.05)., Conclusion: MHZSC is effective and safe in treatment of acute upper respiratory tract infection of external wind-cold syndrome.