The impact of transient wind events on an established zooplankton community was observed during a field survey in a coastal region off northern Norway in May 2002. A transient wind event induced a coastal jet/filament intrusion of warm, saline water into our survey area where a semi-permanent eddy was present. There was an abrupt change in zooplankton community structure within 4–7 days of the wind event, with a change in the size structure, an increase in lower size classes less than 1 mm in equivalent spherical diameter (ESD) and a decrease in larger size classes greater than 1.5 mm in ESD. The slope of zooplankton biovolume spectra changed from −0.6 to −0.8, consistent with the size shifting towards smaller size classes. This study shows that even well established zooplankton communities are susceptible to restructuring during transient wind events, and in particular when wind forcing induces horizontal currents or filaments.
The paper focuses on the material mechanics properties of reinforced concrete and steel casing composite concrete under pseudo-static loads and their application in structure. Although elevated pile-group foundation is widely used in bridge, port and ocean engineering, the seismic performance of this type of foundation still need further study. Four scale-specimens of the elevated pile-group foundation were manufactured by these two kinds of concrete and seismic performance characteristic of each specimen were compared. Meanwhile, the special soil box was designed and built to consider soil-pile-superstructure interaction. According to the test result, the peak strength of strengthening specimens is about 1.77 times of the others and the ultimate displacement is 1.66 times of the RC specimens. Additionally, the dissipated hysteric energy capability of strengthening specimens is more than 2.15 times of the others as the equivalent viscous damping ratio is reduced by 50%. The pinching effect of first two specimens is more obvious than latter two specimens and the hysteretic loops of reinforced specimens are more plumpness. The pseudo-static tests also provided the data to quantitatively assessment the positive effect of steel casing composite concrete in aseismatic design of bridge
Difference in isozymes and activities of peroxidase (POD) and superoxide dismutase (SOD) in two barley (Hordeum vulgare L.) genotypes differing in salt tolerance (Gebeina, tolerant; Quzhou, sensitive) was investigated using a hydroponic experiment. The activities of both enzymes were significantly increased when the plants of the two barley genotypes were exposed to salt stress, with salt-tolerant genotype being generally higher than the sensitive one. The variation in the POD and SOD isozymes was dependent on barley genotype, salt level and exposure time. When the plants were exposed to salt stress for 10 days, two new POD isozymes were found, Rm0.26 (Rm, relative mobility of enzyme to dye) in Gebeina and Rm0.45 in Quzhou. Both isozymes disappeared after 20 days of salt stress, but Rm0.26 appeared again 30 days after the stress. Two new SOD isozymes of Rm0.19 and Rm0.46 were found in Gebeina when exposed to NaCl for 10 days, but only Rm0.46 in Quzhou. As the time of salt stress extended, more new SOD isozymes were detected, Rm0.35 in both genotypes in all different salt treatments and Rm0.48 in Gebeina under 200 mM NaCl stress. At 30 days after the stress, all the new SOD isozymes disappeared except for Rm0.48 in Gebeina under 200 mM NaCl stress. The results suggest that the increased POD and SOD activities could be partly due to the formation of some new isozymes and the tolerant variety had better ability to form new isozymes to overcome salt stress.
Mycorrhizal mycelium can simultaneously colonize two and more neighboring plants to form common mycelium network (CMNs), whereas the information regarding CMN effects on endogenous signal substances is limited. In this study, a rootbox was separated by 37- or 0.45-μm mesh to establish donor chamber (the presence of roots and hyphae) and receptor (hyphae presented or not, free of roots) chamber, where an arbuscular mycorrhizal (AM) fungus Paraglomus occultum was inoculated into trifoliate orange seedlings of donor chamber to illustrate the underground communications of signal substances by CMNs. Mycorrhizal colonization resulted in better plant growth performance and greater root morphology in donor and receptor plants. AM inoculation increased significantly the root nitric oxide (NO) and calmodulin (CaM) levels of donor plants, regardless of 37- and 0.45-μm mesh, and subsequent CMNs induced higher root NO and CaM levels in receptor plants. Mycorrhizal colonization did not produce significant changes in root zeatin riboside (ZR) levels of donor plants, but CMN hyphae modulated lower root ZR levels of receptor plants. Mycorrhizal inoculation and subsequent CMN hyphae induced lower root gibberellin levels of donor and receptor plants, and only CMN hyphae produced lower root methyl jasmonate concentrations of receptor plants. Our results first reveal the underground communication of CaM, NO, and ZR by CMNs with P. occultum between trifoliate orange seedlings.
Steel enterprises, as one type of major industrial pollution source, have been facing great environmental pressure. Integrating environmental considerations into the steelmaking process is now one of the major priorities of the steel industry. A method for evaluating environmental performance is presented in this paper. The proposed method considers the procedure for environmental performance comparison of design alternatives as a multi-criteria decision-making (MCDM) problem. An integrated environmental index for the steel- making process is proposed and qualified, utilizing the Chinese Standard (emission standard of waste pollutants for iron and steel industry). The pair-wise comparison approach of the analytic hierarchy process (AHP) is employed for solving the MCDM problem. A case study is used to illustrate how the assessment method may be applied and to demonstrate its applicability.
Farnesyl diphosphate synthase (FPS; EC 2.5.1.1/EC 2.5.1.10) catalyzes the synthesis of farnesyl diphosphate, a key intermediate in the biosynthesis of sesquiterpenes. This present study described the cloning and characterization of a cDNA encoding FPS from leaves of Michelia chapensis Dandy (designated as McFPS, GenBank accession number: GQ214406) for the first time. McFPS was 1,432 bp and contained an open reading frame (ORF) of 1,056 bp, encoding a protein of 351 amino acids with a calculated molecular mass of 40.52 kDa. Bioinformatic analysis revealed that the deduced McFPS had high homology with FPSs from other plant species. Phylogenetic tree analysis indicated that McFPS belonged to the plant FPS group and had the closest relationship with FPS from Chimonanthus praecox. Southern blot analysis revealed that there were at most two copies of McFPS gene existed in M. chapensis genome. The organ expression pattern analysis showed that McFPS expressed strongly only in leaves, and there were no expression in stems and roots, implying that McFPS was an organ-specific expressing gene. Functional complementation of McFPS in a FPS-deficient yeast strain demonstrated that cloned cDNA encoded a farnesyl diphosphate synthase.
Aiming at the non-linearity of state equation and observation equation of SSP (Siemen Schottel Propulsor) propulsion motor, an improved particle filter algorithm based on strong tracking extent Kalman filter (ST-EKF) was presented, and it was imported into the marine SSP propulsion motor control system. The strong tracking filter was used to update particles in the new algorithm and produce importance densities. As a result, the problems of particle degeneracy and sample impoverishment were ameliorated, the propulsion motor states and the rotor resistance were estimated simultaneously using strong track filter (STF), and the tracking ability of marine SSP propulsion motor control system was improved. Simulation result shown that the improved EPF algorithm was not only improving the prediction accuracy of the motor states and the rotor resistance, but also it can satisfy the requirement of navigation in harbor. It had the better accuracy than EPF algorithm
A heterologous prime-boost vaccination regime with DNA and recombinant vaccinia virus (rvv) vectors expressing relevant antigens has been shown to induce effective immune responses against several infectious pathogens. In this study, we describe the effectiveness of the prime-boost strategy by immunizing dogs with a recombinant plasmid followed by vaccinia virus, both of which expressed the glutamic acid-rich protein (BgGARP) of Babesia gibsoni. The dogs immunized with the prime-boost regime developed a significantly high level of specific antibodies against BgGARP when compared with the control groups. The antibody level was strongly increased after a booster immunization with a recombinant vaccinia virus. Two weeks after the booster immunization with a recombinant vaccinia virus expressing BgGARP, the dogs were challenged with B. gibsoni parasite. The dogs immunized with the prime-boost regime showed partial protection, manifested as a significantly low level of parasitemia. These results indicated that this type of DNA/rvv prime-boost immunization approach may have use against B. gibsoni infection in dogs.