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Numerical simulation of turbulent combustion is a key tool for aeroengine design.Due to the need of high-precision model to Navier-Stokes equation,numerical simulation of turbulent combustion requires huge amount of calculations,and the phy-sicochemical models causes the flow field to be extremely complicated,making the load balancing a bottleneck for large-scale pa-rallelization.We port and optimize the numerical simulation method of turbulent combustion on a powerful computing server,DGX-2.We design the threading method of flux calculation and use Roofline model to guide the optimization.In addition,we design an efficient communication method and propose a multi-GPU parallel method for turbulent combustion based on high-speed interconnection of DGX-2.The results show that the performance of a single V100 GPU is 8.1x higher than that on dual-socket Intel Xeon 6248 CPU node with 40 cores.And the multi-GPU version on DGX-2 with 16 V100 GPUs achieves 66.1x speedup,which is higher than the best performance on CPU cluster.

Comprehensive Summary pH is an important stimuli‐responsive signal because deprotonation‐protonation process is crucial for many life functions. Photoacid is a kind of photoresponsive group that can release protons upon irradiation. This property makes invasive pH control can be replaced by noninvasive light control. However, photoacid is rare. In this work, macrocyclic calixpyridinium was found to be used as a photoacid to release protons from acidic methylene under the irradiation of a 254 nm UV lamp. When the solution of calixpyridinium−disulfonated xantphos aggregates were irradiated by a 254 nm portable UV lamp, disulfonated xantphos was able to receive the protons released from calixpyridinium. This noninvasive photocontrolled proton transfer not only replaces an invasive pH regulation but also achieves a synergistic function. The deprotonation of calixpyridinium and the protonation of disulfonated xantphos can occur simultaneously to disrupt the aggregates. Moreover, the photoresponsive disassembly is reversible by heating. This photoresponsive material was further applied as a photocontrolled release model. In addition, a dissipative assembly was successfully designed based on this photoresponsive disassembly. This study supplies a generalized strategy to construct pH‐responsive biocompatible materials with light‐control properties by using macrocyclic calixpyridinium and its matched various guests in water. [ABSTRACT FROM AUTHOR]

Abstract: A rigorous model for absorption of CO2 into aqueous 2-amino-2-methyl-1-propanol (AMP) was investigated at a temperature of 303K using a double stirred-cell absorber with a planar gas–liquid interface. It was demonstrated that the kinetics region of absorption CO2 into aqueous AMP was the fast pseudo-first order reaction regime. The mass transfer-reaction kinetics equilibrium model according to the film theory is satisfactory to represent CO2 absorption into aqueous AMP. The model predictions had been found to be in good agreement with the experimental results. And the proposed model could handle the prediction much more effectively when CO2 loading was much smaller. [Copyright &y& Elsevier]

Background & Objective: Snake venom phospolipase A2 (PLA(2)), a large family of homologous (14 ku) soluble proteins, exerts diverse pharmacologic activities as well as enzymatic activities. So far, the structure and function of terrestrial snake PLA(2), especially the relationship of its enzymatic and pharmacologic activities have been studied extensively, but the investigation of sea snake PLA(2) are limited. This study was to investigate the in vitro and in vivo antitumor effects of recombinant sea snake basic PLA(2) (rSSBPLA(2)) and its mutants rN48 and rK4 from sea snake Lapemis hardwickii venom, and to explore the influence of 2 residues related with the enzymatic activity on the antitumor effects., Methods: Site-directed mutagenesis of the 2 conserved residues related with enzymatic activity (His48 mutated to Asn and Asp49 mutated to Lys) was performed. The inhibitory effects of rSSBPLA(2), rN48 and rK49 on proliferation of human myeloid leukemia cell line HL-60, human neuroblastoma cell line SK-N-SH, human gastric cancer cell line MGC-803, and human liver cancer cell line HepG2 were assessed by MTT assay. Their antitumor effects on sarcoma cell line S180 xenograft and EAC ascites cancer model in mice were detected., Results: The relative enzymatic activities of rN48 and rK49 were 0 and 5% of that of rSSBPLA(2). The 50% inhibitory concentration (IC(50)) of rSSBPLA(2) for HL60, SK-N-SH, and MGC-803 cells were (45.28+/-0.09) microg/ml, (57.07+/-0.12) microg/ml, and (69.34+/-0.35) microg/ml, respectively, but it had no inhibitory effect on proliferation of HepG2 cells. rSSBPLA(2) obviously inhibited growth of S180 xenograft in miceû the inhibitory rates were 50.8%, 43.2%, 38.2%, and 55.5%, respectively, under the dose of 2 mg/kg (qd x 10), 2 mg/kg (q2d x 5), 4 mg/kg (qd x 1) and 4 mg/kg (q5d x 2). The inhibitory rate of EAC model was 33.5% under the dose of 4 mg/kg (q5d x 2). The inhibitory rates were significantly higher in test groups than in control groups (P<0.01). rN48 and rK49 had no inhibitory effect on proliferation of the 4 tumor cell lines and on growth of the xenograft tumors., Conclusion: The antitumor effect of rSSBPLA(2) may be closely related with its enzymatic activity.

Three different genes named sn311, sn316 and sn285 were discovered by large-scale randomly sequencing the high quality cDNA library of the venom glands from Hydrophiinae Hydrophis cyanocinctus Daudin. Sequence analysis showed that these three genes encoded three different short chain alpha-neurotoxins of 81 amino acids, which contained a signal peptide of 21 amino acids and followed by a mature peptide of 60 amino acids. Amino acid comparison reveals that mature peptides of sn311 and sn316 are highly homologous, with the only variance at position 46, which is Lys46 and Ser46, respectively. Whereas the mature peptide of sn285 lacks the most conserved amino acids in short chain alpha-neurotoxins, Asp31 and Arg33. The coding sequences of three neurotoxins were cloned into a thioredoxin (TRX) fusion expression vector (pTRX) and expressed as soluble recombinant fusion proteins in E. coli. After purification, approximately 10 mg/l recombinant proteins with the purity up to 95% were obtained. These three recombinant proteins are designated as rSN311, rSN316 and rSN285, they have a molecular weight of 6.963, 6.920 and 6.756 kDa, respectively, which are similar to those predicted from amino acid sequences. LD50 values of rSN311, rSN316 and rSN285 are 0.0827, 0.095, and 0.0647 mg/kg to mice, respectively. Studies on effects of these recombinant proteins on neuromuscular transmission were carried out, and results indicate that they all can produce prompt blockade of neuromuscular transmission, but display distinct biological activity characteristic individually. The results from UV-circular dichroism (CD) spectra indicate that they share similar secondary structure compared to other identified alpha-neurotoxins, and no significant structural differences in these recombinant proteins are observed.

A cDNA expression library of the tentacles of Sagartia rosea was constructed. The cDNA was cloned into eukaryotical expression plasmid pcDNA3. SMART protocol was used for cDNA library construction and bioinformatics analysis was carried out. 71 novel EST clones were obtained from 130 sequences in the library, of which there were 21 full-length clones, including cytolysin genes, flourescent protein, ubiquinol-cytochrome C reductase gene, elongation factor, ferritin gene riboflavin kinase gene, ribosomal protein. This provides a base for further investigating their biological activity and application.

Three full-length cDNA from Lapemis hardwickii Gray, (namely PLA(2)-8, PLA(2)-9 and PLA(2)-384), encoding phospholipase A(2) (PLA(2)), were isolated and sequenced. These cDNA sequences were composed of 456 bp, 438 bp and 438 bp, encoding a signal peptide of 27 amino acids and a mature peptide of 125, 119 and 119 amino acids, respectively. The analysis results by computer indicated PLA(2)-8, PLA(2)-9and PLA(2)-384 has a pI of ca. 4.8, 7.8 and 8.4, respectively. Sequence analysis of amino acid and prediction of secondary structure suggested that these isoforms of PLA(2) belong to class I PLA(2) family. PLA(2)-8 was highly homologous (81%) to Notechis scutatus scutatus (Australian tiger snake) PLA(2), PLA(2)-9 and PLA(2)-384 showed fairly high sequence homology (90%) to Enhydrina schistosa (beaked sea snake) PLA(2), indicating that they might have similar functions. These results reflect the diversity of Lapemis hardwickii Gray PLA(2) genes. The successful cloning of these isoenzyme genes of sea snake PLA(2) may provide new information for the study on structure-function relationship of PLA(2) family and its possible molecular mechanism.

Three cDNA clones, sn12, sn36 and sn160, encoding isoforms of postsynaptic short-chain neurotoxins, were cloned by screening a cDNA library of the venom from Hydrophiinae, Lapemis hardwickii Gray. The sequences of three cDNA clones encoded proteins consisting of 60 amino acid residues. There was only one amino acid substitution among the three isoforms SN12, SN36 and SN160 at the position 46 of mature proteins, and they were Pro(46), His(46) and Arg(46), respectively. The three molecules were expressed in Escherichia coli and the recombinant proteins were characterized. Different LD(50) were obtained, namely 0.0956 mg/kg, 0.3467 mg/kg and 0.2192 mg/kg, when the SN12, SN36 and SN160 were injected into Kunming mice(i.p.). In analgesic effect assayed by the acetic acid-induced writhing method, SN12 and SN160 showed similar analgesic effect, but SN36 had effects significantly different with the other two. Our studies suggested that the amino acid residues on position 46 could affect the combination between the postsynaptic short-chain neurotoxins and the nicotinic acetylchoine receptor, since different amino acid substitution resulted in different biological activities.