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Drought causes water shortage and consequent retardation of plants growth and development. Therefore, improving the drought tolerance of plants is necessary for expanding cultivation and resource promotion. Increasing evidence indicates that phospholipase is involved in the response of plants to drought stress. The objective of this study was to create new drought-tolerant chrysanthemum germplasm, which lays a foundation for the study of the molecular mechanism of phospholipase mediated stress response in chrysanthemum. CmPLDα has the closest relationship with sunflower HaPLDα, and belongs to the PLDα family. CmPLDα over-expressing plants showed a slight shrinking under 20% PEG6000 treatment. The survival rate increased significantly by 1.7−1.8 times that of the wild type. Relative water content (RWC) of CmPLDα over-expressing plants were nearly 10% higher than that of the wild type. Relative electrical conductivity and MDA content were significantly lower than those of the wild type. ABA content of the over-expression lines Z1, Z2 were 1.3 and 1.22 times that of wild type, but ABA content of antisense lines F1, F2 was approximately 0.83 and 0.81 of those of wild type. Most plants of antisense transgenic lines F1, F2 were wrinkled, with a wilting index of 5 and 6, and the survival rate was also lower than that of the wild type after recovery growth. RWC of antisense lines were lower than over-expression lines, relative electrical conductivity and MDA content were significantly higher than those of the wild type. In summary, CmPLDα could enhance tolerance of chrysanthemum to drought conditions.

A new polyketide, 9(E)-3-(5,8-dihydroxynon-3-en-1-yl)-5,6-dihydroxy-2,6-dimethylcyclohex-2-enone (1), and one known compound, 5-chloroisorotiorin (2), were isolated from the mangrove-derived fungus Phomopsis sp. TJM1-5. Their structures were determined by extensive NMR and MS analyses, while the absolute configurations of C-5 and C-6 were established based on experimental and calculated electronic circular dichroism spectra. Compound 2 was isolated from the genus of Phomopsis for the first time. Compounds 1 and 2 were evaluated for their antibacterial activity against five pathogenic bacteria.

A new α,β-unsaturated 7-ketone sterol, 5β,6β-epoxy-3β, 15α-dihydroxy-(22E,24R)-ergosta-8(14),22-dien-7-one (1), along with five known sterone derivatives, 5β,6β-epoxy-3β,7α-dihydroxy-(22E,24R)-ergosta-8(14),22-dien-15-one (2), 5β,6β-epoxy-3β,7α,9α-trihydroxy-(22E,24R)-ergosta-8(14),22-dien-15-one (3), 3β,9α,15α-trihydroxy-(22E,24R)-10(5→4)-abeo-ergosta-6,8(14),22-trien-5-one (4), 3,15-dihydroxyl-(22E,24R)-ergosta-5,8(14),22-trien-7-one (5) and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3,15-dione (6) were isolated from the mangrove-derived fungus Phomopsis sp. MGF222. Their structures were established on the basis of extensive spectroscopic data and comparison with the data of literature. Compound 2 showed weak antibacterial activity against Micrococcus tenuis with the MIC value of 28.2 (±0.52) μM. Compound 5 exhibited moderate antibacterial activity against Staphylococcus aureus with the MIC value of 14.6 (±0.47) μM.

A new

The effects of CO2enrichment on growth and development ofImpatiens hawkeri, an important greenhouse flower, were investigated for the purpose of providing scientific basis for CO2enrichment to this species in greenhouse. The plants were grown in CO2-controlled growth chambers with 380 (the control) and 760 (CO2enrichment) μmol⋅mol-1, respectively. The changes in morphology, physiology, biochemistry, and leaf ultrastructure ofImpatienswere examined. Results showed that CO2enrichment increased flower number and relative leaf area compared with the control. In addition, CO2enrichment significantly enhanced photosynthetic rate, contents of soluble sugars and starch, activities of peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), but reduced chlorophyll content and malondialdehyde (MDA) content. Furthermore, significant changes in chloroplast ultrastructure were observed at CO2enrichment: an increased number of starch grains with an expanded size, and an increased ratio of stroma thylakoid to grana thylakoid. These results suggest that CO2enrichment had positive effects onImpatiens, that is, it can improve the visual value, promote growth and development, and enhance antioxidant capacity.

The living creature evolve into various kinds of animals after a long time, there also is the law that includes evolvement, variation and complex at the formation of all machines. The machine evolution laws were analysed and concluded from the standpoint of mechanism in this text. The diagram of evolution form listed on show reflects the internal evolution law of mechanism. The multiple development of mechanical structure relys on the evolvement of and the variation of machine parts. The birth of pioneer product also relys on the evolutionary logic to expand.

The mixing mechanism of a punched agitator used in solid-liquid suspension system was studied basing on the enstrophy and energy dissipation of the vortex theory. The effects of the configuration parameters on stirring performance were discussed. The results show that efflux from such punched agitator with simple structure can not only strengthen vortex diffusion, but also reduce the power consumption by diminishing the projection area in the direction which the paddles round. Obviously, this is beneficial to lower critical suspension velocity and promote mixing efficiency in stirring tank. It is indicated that the punched agitator owning quite broad application prospects.

The structure and operating principle of rolling movable teeth reducer are introduced in this paper. Through the virtual prototype technology, the modeling of rolling movable teeth reducer is made by Pro/E software,and is had the kinematics simulation and dynamic analysis by ADAMS software. The simulation results show that the speed curves of the input shaft and the output shaft of rolling movable teeth reducer coincide with the theory transmission. It proves correctness of virtual prototype. The mechanical properties of rolling movable teeth reducer is obtained by the time-domain graph of meshing force. It provides the basis for the optimization design and engineering analysis of reducer.

From the parametric modeling, the APDL tool can be used in ANSYS to build the finite element model of rhombic wire wound vessel. Only a small amount of parameters have to be input in order to accomplish the whole process of program development such as constructing model, meshing, creating contact pairs, bringing restrictions and loads to bear on vessels as well as solving and post-processing. It can be easy to use the developed batch program to achieve the finite element analysis of vessels and get the influence of interbedded friction on the load capacity of rhombic wire wound vessel under different working pressures.

Fifteen microsatellite loci were developed to examine the population structure of Japanese scallop, Patinopecten yessoensis. These markers were tested in samples from two geographically distant populations: the Sakhalin Island (Russia) and Dalian City (China). The mean numbers of alleles, observed and expected heterozygosities between the two populations were summarized by locus, but none of them show significant divergence between the two populations. Most loci conformed to Hardy–Weinberg expectation with the exception of loci HLJX-06, HLJX-12, HLJX-13 and HLJX-28, which had heterozygote deficits.

This paper takes diameter 1400 mm urea reactor as analysis targets, the study considered laminates space multilayered vessel stress field distribution, in the theoretical analysis on the basis of a large commercial software ANSYS based on the finite element numerical simulation validation, full consideration Clearance of laminates, It proves that formula of P.G. Pimshtein More suited to multi-layer containers stress field than formula of Lame. it provides a theoretical basis to such containers for the actual pilot fatigue analysis.

Rainbow trout are cultured widely throughout the world for supplementation in natural ecosystems and for commercial aquaculture. In 1959 it was firstly introduced to China from Korea. After introduction from America and other countries such as Norway, Denmark, and so on, rainbow trout were now cultured in about 20 provinces in China. In this study, microsatellite DNA was employed to assess the genetic variations between 6 cultured populations of rainbow trout (American golden trout, American Donaldsons, Norway, Denmark, Finland, and Bohaizhan). The results showed that in these 6 cultured populations the average number of allele (A) was 2.89 to 4.22; average number of effective allele (Ne) was 2.15 to 2.78; the value of average observed heterozygosity (Ho) in six populations was 0.4802 to 0.6786; the value of average excepted heterozygosity (He) was 0.5052 to 0.6211; and the value of average polymorphism information content (PIC) was 0.4298 to 0.5762. Hardy-Weinberg equilibrium analysis revealed that all of these 6 populations showed a remarkable genetic disequilibrium at loci AY039634, AY039638, AY0396466. Only at locus AF375034 all of 6 populations showed equilibrium. The genetic distance of six cultured populations was calculated and cluster analysis was also carried out.