Comparison of lipids in organs of the starfish Asterias amurensis associated with different treatments

Lipids were extracted from organs of the starfish Asterias amurensis associated with different treatments(raw-control,boiling and heating),and then analyzed for lipid content,lipid oxidation index,lipid classes and fatty acid composition.Results showed that boiling softened the hard starfish shells,thus facilitating the collection of starfish organs.As compared with raw organs,the boiled organs had lower water content and higher lipid content,possibly due to the loss of water-holding capacity caused by protein denaturation.Both boiling and heating increased the peroxide value(PV),thiobarbituric acid(TBA) value and carbon value(CV) of lipids.Despite slight increases in the content of complex lipids,associated lipid composition had no substantial variations upon boiling and heating.For simple lipids,the content of 1,2-diglyceride decreased in boiled and heated organs,with free fatty acids observed on thin layer chromatography(TLC).However,neither boiling nor heating significantly changed the fatty acid compositions of simple or complex lipids in starfish organs,suggesting that these two treatments had no significant effects on complex lipids in starfish organs.Together,our results indicated that boiling of starfish soon after capture facilitated the handling and extraction of useful complex lipids consisting of abundant glucosylceramide and eicosapentaenoic acid(EPA)-bounded phospholipids.     

Weak lensing magnification reconstruction with the modified internal linear combination method

Measuring weak lensing cosmic magnification signal is very challenging due to the overwhelming intrinsic clustering in the observed galaxy distribution.In this ...     

The Key Techniques and Design Features of YH-1 Mars Probe

In this paper, the function and composition as well as the key techniques (ultra-long distance communication, attitude determination and control, thermal control, ultra-low temperature acclimatization, etc.) of China's first Mars probe are analyzed. In combination with practical engineering conditions, the solutions of these key techniques are given. The design features of the probe are summarized, as a reference for developing the probes of the subsequent related missions in China.     

Response of the western North Pacific subtropical ocean to the slow-moving super typhoon Nanmadol

Based on in-situ observation, satellite and reanalysis data, responses of the western North Pacific subtropical ocean(WNPSO) to the slow-moving category 5 super typhoon Nanmadol in 2011 are analyzed. The dynamical response is dominated by near-inertial currents and Ekman currents with maximum amplitude of 0.39 m/s and 0.15 m/s, respectively. The near-inertial currents concentrated around 100 m below the sea surface and had an e-folding timescale of 4 days. The near-inertial energy propagated both upward and downward, and the vertical phase speed and wavelength were estimated to be 5 m/h and 175 m, respectively. The frequency of the near-inertial currents was blue-shifted near the surface and redshifted in ocean interior which may relate to wave propagation and/or background vorticity. The resultant surface cooling reaches -4.35℃ and happens when translation speed of Nanmadol is smaller than 3.0 m/s.When Nanmadol reaches super typhoon intensity, the cooling is less than 3.0℃ suggesting that the typhoon translation speed plays important roles as well as typhoon intensity in surface cooling. Upwelling induced by the slow-moving typhoon wind leads to typhoon track confined cooling area and the right-hand bias of cooling is slight. The mixed layer cooling and thermocline warming are induced by wind-generated upwelling and vertical entrainment. Vertical entrainment also led to mixed layer salinity increase and thermocline salinity decrease, however, mixed layer salinity decrease occurs at certain stations as well. Our results suggest that typhoon translation speed is a vital factor responsible for the oceanic thermohaline and dynamical responses, and the small Mach number(slow typhoon translation speed) facilitate development of Ekman current and upwelling.     

Electrochemical corrosion behavior of hot dip coating in artificial seawater

INTR0DUCnONAlloycoatingscandetivelyproteCtsteelagainstcormsioninseri0uscormsionenvir-orunent,suchasthedrinesplashandtidalzones-TwoInainhodiptincaldrinumalloycOaingswidelyusedcommroiallyareGalfancoaing(contalningZn-5wt%kl-us)devel-oPedbytheIntemaionaltalZincReenhheZaionandhocoating(c0n-talningZn-55Wt%Al-1.6Wt%Si)develoPedbytheBethlehemSteelCorpOration-Anewrinc-basedalloycOaingdevel0PedbyNortheaStemUniversityisdiscussedinthesPaperbyelecthehendcalmethod.FromSun(l996),welmOWthecorms…     

Broader pattern of tandem repeats in the mitochondrial control region of Perciformes

Perciformes, the largest order of vertebrates with 20 suborders, is the most diverse fish order that dominates vertebrate ocean life. The complete mitochondrial control region (CR) of Trichiurus japonicus (Trichiuridae, Scombroidei) and Pampus sp. (Stromateidae, Stromateoidei) were amplified and sequenced. Together with data from GenBank, the tandem repeats in the mitochondrial CR from 48 species, which covered nine suborders of Perciformes, are reported in this study. The tandem repeats tend to be long in the suborder Percoidei and Stromateoidei. The identical repeats in 21 species of Cichlidae suggest a common origin and have existed before species divergence. Larimichthys crocea shows tandem repeats instead of the typical structure of the central conserved sequence blocks, which was first reported in Perciformes and vertebrates. This might have resulted from interruption of the polymerase activity during the H-strand synthesis. The four broader patterns presented here for the tandem repeats, including those in both the 5′ and 3′ ends, only in the either 5′ or 3′ end, and in the central conserved domain of the control region, will be useful for understanding the evolution of species.     

Identification and sequence of a cDNA clone corresponding to a gene involved in development ofUndaria pinnatifida

During the induction of gamete-producing gametangia, induced gametophytes were collected at 4 days intervals (0,4,8,12 d) and total RNAs were isolated by CsCl gradient ultracentrifugation. Some stage-specific expressed mRNAs were identified by differential display of mRNAs from different developing stages of the gametophytes. The cDNA of one specific mRNA was verified, cloned and sequenced. This gene was specifically expressed during 4 days of induction, and had partial homologous sequence with tobacco IAA-binding protein gene. It suggests that this cDNA may represent a gene which is related to the IAA regulating function during the development of the gametophytes.

     

The Characteristics and Related Problems of the Orbits Around the Earth-Moon Libration Points

Due to the specific dynamics, the probes located at the halo orbits or Lissajous orbits around the Earth-Moon collinear libration point L₁ or L₂ are always studied in the synodic system to understand their trajectories. In fact, they are also orbiting the Earth in a distant Keplerian ellipse. Because of their intrinsic orbital instability, in the orbit prediction the initial errors propagate more prominently than those of the normal orbiting satellites, this requires special attention in the orbit design, maneuver, and control. Despite of all this, they are similar to the normal orbiting satellites in orbit determination and hardly require other special attentions. In this paper, the quantitative results of error propagation under the unstable dynamics, together with the theoretical analysis are presented. The results of precise orbit determination and short-arc orbit predictions are also shown, and compared with the results from the Beijing Aerospace Control Center.