Supercritical fluid extraction of all-trans-lycopene from tomato

A procedure is proposed for the supercritical fluid extraction of all-trans-lycopene from tomato using carbon dioxide at 40 degrees C without modifier. The present method minimizes the risk of degradation via isomerization and oxidation of health-promoting ingredients, such as lycopene. The effect of different experimental variables on the solvating power of the supercritical fluid was evaluated in terms of both the selectivity achievable in the process and the yield of the extraction of all-trans-lycopene. Satisfactory separations of the all-trans-lycopene isomers from the cis counterparts were achieved using a C(30) column. The obtained extract contained 88% all-trans-lycopene and 12% cis-lycopene.     

1-甲基环丙烯延长菠菜采后保鲜期的研究

分别对经0.1、1.0μL.L-1浓度的1-甲基环丙烯(1-MCP)处理和未经1-MCP处理的离体菠菜叶片的衰老特性进行研究。结果表明,与对照相比,经1-MCP处理的菠菜叶片在避光、23℃条件下贮藏6 d后,叶绿素含量和光系统Ⅱ最高光量子产量较高,溶质渗漏量较低,说明1-MCP处理可延缓菠菜叶片的衰老。贮藏3 d后,经1-MCP处理的菠菜叶片乙烯生成量增加,随后又下降至对照水平。经1-MCP处理的菠菜叶片中具有较高的抗坏血酸和谷胱甘肽含量及对于这两种物质较低的氧化还原比率。1-MCP处理还可以减少菠菜叶片中的铵盐积累及蛋白质的降解。综合上述结果可以得出,通过1-MCP抑制菠菜叶片对乙烯作用的敏感性可有效延长菠菜的采后保鲜期。     

甲酸对肉仔鸡生产性能、消化率、肠组织形态和血浆代谢产物的影响

研究饲粮甲酸对肉仔鸡生产性能、消化率、肠组织形态和血浆代谢产物的影响。120只罗斯雄性肉仔鸡,在实验室饲养,饲养期为1～42日龄。试验设4个处理:对照组(C);添加阿维霉素,水平为10 mg·kg~(-1)(AV);添加甲酸,水平为5g·kg~(-1)(FA5)和添加甲酸,水平为10 g·kg~(-1) (FA10)。各处理间,雄性肉仔鸡的增重、饲料采食量或饲料转化率没有显著差异。42日龄时,育成鸡饲粮中,各种添加物对雄性肉仔鸡回肠干物质消化率有一定影响;与其他处理相比,阿维霉素和添加水平为10 g·kg~(-1)的甲酸,轻度增加回肠干物质消化率。添加水平为5 g·kg~(-1)和10g·kg~(-1)的甲酸对空肠pH没有影响,试验结果不能清楚显示甲酸对肠组织形态的积极作用。各处理间,血液代谢产物没有不同,血浆钙、磷水平不受甲酸添加物影响。结论:卫生状况良好的肉仔鸡,饲粮甲酸对生产性能、肠组织形态或血浆代谢产物水平没有清楚的积极的影响;然而,对回肠营养物质消化率有轻度积极的影响。     

The magnetic field of saturn: pioneer 11 observations

The intrinsic magnetic field of Saturn measured by the high-field fluxgate magnetometer is much weaker than expected. An analysis of preliminary data combined with the preliminary trajectory yield a model for the main planetary field which is a simple centered dipole of moment 0.20 +/- 0.01 gauss-Rs(3) = 4.3 +/- 0.2 x 10(28) gauss-cm(3) (1 Rs = 1 Saturn radius = 60,000 km). The polarity is opposite that of Earth, and, surprisingly, the tilt is small, within 2 degrees +/- 1 degrees of the rotation axis. The equatorial field intensity at the cloud tops is 0.2 gauss, and the polar intensity is 0.56 gauss. The unique moon Titan is expected to be located within the magnetosheath of Saturn or the interplanetary medium about 50 percent of the time because the average subsolar point distance to the magnetosphere is estimated to be 20 Rs, the orbital distance to Titan.     

Magnetic fields at uranus

The magnetic field experiment on the Voyager 2 spacecraft revealed a strong planetary magnetic field of Uranus and an associated magnetosphere and fully developed bipolar masnetic tail. The detached bow shock wave in the solar wind supersonic flow was observed upstream at 23.7 Uranus radii (1 R(U) = 25,600 km) and the magnetopause boundary at 18.0 R(U), near the planet-sun line. A miaximum magnetic field of 413 nanotesla was observed at 4.19 R(U ), just before closest approach. Initial analyses reveal that the planetary magnetic field is well represented by that of a dipole offset from the center of the planet by 0.3 R(U). The angle between Uranus' angular momentum vector and the dipole moment vector has the surprisingly large value of 60 degrees. Thus, in an astrophysical context, the field of Uranus may be described as that of an oblique rotator. The dipole moment of 0.23 gauss R(3)(U), combined with the large spatial offset, leads to minimum and maximum magnetic fields on the surface of the planet of approximately 0.1 and 1.1 gauss, respectively. The rotation period of the magnetic field and hence that of the interior of the planet is estimated to be 17.29+/- 0.10 hours; the magnetotail rotates about the planet-sun line with the same period. Thelarge offset and tilt lead to auroral zones far from the planetary rotation axis poles. The rings and the moons are embedded deep within the magnetosphere, and, because of the large dipole tilt, they will have a profound and diurnally varying influence as absorbers of the trapped radiation belt particles.     

海峡西岸社会主义新农村建设中的几个主要矛盾

海峡西岸社会主义新农村建设面临着一系列两难的问题，集中体现在农村经济发展与综合发展、政府主导与农民主体、资源存量不活与增量不足、公共品供给与需求、新农村建设与工业化和城镇化、统筹城乡发展与体制机制滞后这六大矛盾。要统筹兼顾，妥善处理，把握好矛盾各方面的平衡度，使这些矛盾内部之间以及矛盾之间围绕建设海峡西岸社会主义新农村的总体价值取向达到一种新的优化平衡，为新农村建设注入新的动力，拓展新的境界。     

Signal-driven computations in speech processing

Learning a language requires both statistical computations to identify words in speech and algebraic-like computations to discover higher level (grammatical) structure. Here we show that these computations can be influenced by subtle cues in the speech signal. After a short familiarization to a continuous speech stream, adult listeners are able to segment it using powerful statistics, but they fail to extract the structural regularities included in the stream even when the familiarization is greatly extended. With the introduction of subliminal segmentation cues, however, these regularities can be rapidly captured.     

冬播麦区Glu-1和Glu-3位点变异及1B/1R易位与小麦加工品质性状的关系

 贮藏蛋白组成是决定小麦加工品质的重要因素。本文调查了我国冬播麦区251份主栽品种和高代品系的高分子量麦谷蛋白亚基（HMW-GS）、低分子量麦谷蛋白亚基（LMW-GS）和1B/1R易位的分布状况，研究了它们与加工品质性状的关系。结果表明，品质较差的HMW-GS N、7+9、2+12和LMW-GS Glu-A3a与Glu-B3j（1B/1R易位）在冬播麦区分布较广，频率分别为39.4%、45.0%、59.8%、37.1%和44.6%。HMW-GS和LMW-GS等位变异对籽粒蛋白质含量影响较小，对SDS沉降值、和面时间与耐揉性的加性和互作效应达1%的显著水平。按位点对加工品质性状的贡献大小，Glu-D1>Glu-B3>Glu-B1>Glu-A3>Glu-A1；就单个亚基而言，Glu-A1位点，1>2*>N；Glu-B1位点，7+8>14+15>7+9；Glu-D1位点，5+10>4+12>2+12；Glu-A3位点，Glu-A3d>Glu-A3a>Glu-A3c>Glu-A3e，Glu-B3位点； Glu-B3d>Glu-B3b>Glu-B3f >Glu-B3j。1B/1R易位对SDS沉降值、和面时间和耐揉性等加工品质性状有显著负面效应。通过选择优质高低分子量麦谷蛋白亚基和淘汰1B/1R易位系，将有助于提高我国小麦的面筋质量。     

Classification of pumpkin seed oils according to their species and genetic variety by attenuated total reflection Fourier-transform infrared spectroscopy

Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), followed by multivariate treatment of the spectral data, was used to classify seed oils of the genus Cucurbita (pumpkins) according to their species as C. maxima, C. pepo, and C. moschata. Also, C. moschata seed oils were classified according to their genetic variety as RG, Inivit C-88, and Inivit C-2000. Up to 23 wavelength regions were selected on the spectra, each region corresponding to a peak or shoulder. The normalized absorbance peak areas within these regions were used as predictors. Using linear discriminant analysis (LDA), an excellent resolution among all categories concerning both Cucurbita species and C. moschata varieties was achieved. The proposed method was straightforward and quick and can be easily implemented. Quality control of pumpkin seed oils is important because Cucurbita species and genetic variety are both related to the pharmaceutical properties of the oils.