繁缕(Stellaria media (L.) Vill.)种子萌发特性的研究

对繁缕进行温度、光照、低温贮藏、赤霉素和破种皮处理实验,研究不同条件对种子萌发的影响。结果表明,繁缕种子萌发对温度敏感,对光照不敏感,最适宜的萌发温度为12℃,最适光照条件为8 h。低温贮藏处理可有效促进种子萌发,-70℃贮藏后种子萌发率达到93.25%。赤霉素对种子萌芽影响较显著,最适浓度为500 mg/L。破种皮处理后种子萌发效果最好,萌发率达到96.75%,并于5 d萌发完毕。

Identification of Stellaria media by PCR

Aim To provide a rapid and reliable method for identifying the fork medicine Stellaria media （Linn. ） Cyr. （Herba Stellariae mediae） （Caryophyllaceae） from its adulterant Myosoton aquaticure （L.） Fries （Herba Myosoti aquatici） （Caryophyllaceae） by polymerase chain reaction （PCR） technology. Methods A molecular genetic approach has been developed to identify S. media for the first time. 5S-rRNA spacer domain was amplified by PCR from the isolated genomic DNA, and the PCR products were then sequenced. Results The nucleotide sequences of S. media and M. aquaticum were measured to determine their identity. Furthermore, the nucleotide sequences of three Stellaria species, S. vestita, S. longifolia and S. radians, were also measured for the sake of providing the evidence of the biological phylogeny of SteUaria. Diversity between DNA sequence and restriction enzyme mapping among a variety of the species was found in their 5S-rRNA spacer domains. Conclusion The 5S-rRNA spacer domains can be used as a molecular marker for differentiating S. media from M. aquaticum and in phylogenetie studies of Stellaria.

华北地区繁缕属(Stellaria L.)植物叶表皮微形态特征研究

采用光学显微镜,对华北地区分布的繁缕属植物16种2变种,其它4属4种植物的叶表皮微形态进行了观察。结果表明：繁缕属植物叶片的下表皮均存在气孔器,而上表皮仅少数种类缺乏气孔器。气孔器类型比较多样,有不等细胞型、无规则型、无规则四细胞型;表皮细胞主要为不规则型,垂周壁从平直、弓形、浅波状、波状、到深波状;上表皮气孔指数在5.23-31.65之间;下表皮气孔指数在10.02-29.44。叶表皮被毛或无,毛被分为星状毛、腺柔毛、柔毛、绢毛。该研究说明叶表皮的微形态特征在种间差异明显,可以为分种及属间亲缘关系的探讨提供依据,但是对组的划分存在一定的局限性。

中国繁缕(Stellaria chinensis Regel)一新变种

发表了中国繁缕一新变种 ,即缘毛中国繁缕StellariachinensisRegelvar.ciliataC .S .ZhuetH .M .

Dynamics of a stochastic rumor propagation model incorporating media coverage and driven by Lévy noise

With the development of information technology,rumors propagate faster and more widely than in the past.In this paper,a stochastic rumor propagation model incorporating media coverage and driven by Lévy noise is proposed.The global positivity of the solution process is proved,and further the basic reproductive number R_(0) is obtained.When R_(0)<1,the dynamical process of system with Lévy jump tends to the rumor-free equilibrium point of the deterministic system,and the rumor tends to extinction;when R_(0)>1,the rumor will keep spreading and the system will oscillate randomly near the rumor equilibrium point of the deterministic system.The results show that the oscillation amplitude is related to the disturbance of the system.In addition,increasing media coverage can effectively reduce the final spread of rumors.Finally,the above results are verified by numerical simulation.

Microstructure and magnetic properties of granularFePt/(FePt)_(27)Ti_(73) films for ultrahigh-density recording media

FePt granular films were prepared by direct current facing-target magnetron sputtering system onto glass substrates and subsequently in-situ annealed in vacuum. Vibrating sample magnetometer, X-ray diffraction and scanning probe microscope were applied to study the magnetic properties, microstructures, morphologies and domain structures of the samples. （FePt）27Ti73 bilayer films were fabricated at various conditions to investigate the effect of Ti on FePt grains. The results show that without Ti matrix layer, FePt films deposited onto the glass substrates are fcc disordered; with addition of Ti matrix layer, FePt/Ti films form a ternary （FePt）27Ti73 alloy possessing fcc and L10 （111） mixed texture. FePt/（FePt）27Ti73 films with perfectly ordered L10（111） structure and unique magnetic properties can be obtained at Ti thickness of 35nm and substrate temperature of 250℃. The maximum coercivity is more than 240kA/m and the squareness ratio is more than 0.9. The obtained results suggest that the granular FePt/（FePt）27Ti73 films can be applicable to ultrahigh-density magnetic recording media.

The effects of different strength of MS media in solid and liquid media on in vitro growth of Typhonium flagelliforme

Objective: To determine the effects of different strength of Murashige and Skoog(MS)media(full,1/2and1/4) in solid and liquid media on in vitro growth of Typhonium flagelliforme(T. flagelliforme), whereby an optimum media composition can be provided for mass propagation of T. flagelliforme.Methods: Rhizome bud of T. flagelliforme was obtained from the axenic in vitro established T. flagelliforme plantlets in Plant Tissue Culture Laboratory, Universiti Teknologi MARA, Shah Alam. Rhizome bud was used as explant and cultured onto shoot proliferation medium under different strength of MS media(full,1/2,1/4) in solid and liquid culture media.Results: After 6 weeks of culture, the number of shoot, number of leaf, number of root,height of shoot, fresh weight, dry weight and chlorophyll content of T. flagelliforme were analyzed. A comparison was made between liquid and solid culture media. The results revealed that the liquid culture media were more effective for all the growth parameters(shoot height, shoot number, leaf number, root number, fresh weight, dry weight, chlorophyll a and chlorophyll b content) compared to solid culture media. Apart from that,this study revealed the positive relationship between strength of MS media and type of culture media(solid and liquid media) to the growth of T. flagelliforme. Growth of T. flagelliforme was improved when MS strength was increased in liquid media. In contrast, growth of T. flagelliforme was improved when MS strength was decreased in solid media.Conclusions: Through this study, an optimum media composition for mass propagation of T. flagelliforme had been established by observing effects of MS media strength and type of culture media(solid and liquid media) on the growth of T. flagelliforme.

Glyoxylic acid as catalyst:A simple selective synthesis of 1,2-disubstituted benzimidazoles in aqueous media

Glyoxylic acid （5 mol%） performs as a novel highly water-soluble catalyst for the synthesis of 2-aryl-l-arylmethyl-lH- benzimidazoles from a wide range of substituted o-phenylenediamines and various substituted aldehydes in good to excellent isolated yields （85-95%） using water as solvent at ambient temperature. The remarkable advantages offered by this method are easily and inexpensive available catalyst, simple procedure, mild conditions, much faster （20--40 rain） reactions and excellent yields of products.

<i>In-Vitro</i>Regeneration of <i>Citrus sinensis</i>(L.) Osbeck from Mature Seed Derived Embryogenic Callus on Different Solid Basal Media

In-vitro callus induction and regeneration method was developed using different plant growth regulators (PGRs), and basal media (Murashige and Skoog (MS), CHU (N6) and Gamborg (B5) media) of Citrus sinensis (L.) Osbeck. Observations of the effect of PGRs were carried out using different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D),1-naphthalene acetic acid (NAA) and combinations of 2,4-D and NAA using different basal media. This study found Citrus sinensis (L.) Osbeck exhibited a high frequency of callus induction on MS medium supplemented with 3 mg/L 2,4-D and callus induction frequency was 86.7% ± 3.4% whereas N6 and B5 showed lower callus induction frequency of 83.3% ± 8.8% and 82.2% ± 1.9% respectively compared to that of MS media with supplementation of the same hormone. Among the induced calli, the morphological analysis showed only 40% - 50% was embryogenic calli. Regeneration of plantlets from calli was done using different concentrations and combinations of auxin and cytokinin. The study showed that 3 mg/L 6-benzylaminopurine (BAP) supplemented medium has the maximum potential to promote regeneration of Citrus sinensis (L.) Osbeck from embryogenic calli with the frequency of 89.3% ± 8.8% but no regeneration occurred from the non-embryogenic calli. The regenerated plantlets were rooted on MS medium with supplementation of 5 mg/l NAA. These observations in Citrus sinensis (L.) Osbeck regeneration will be helpful for genetic improvement with desired traits.

Organic Media Enhanced Spectrofluorimetric Determination of L-Ascorbic Acid

A novel spectrofluorimetric method for the determination of L ascorbic acid is proposed. It is based on the inhibition of L ascorbic acid on the formation of 2,3 diaminophenazine, which is an oxidation product of o phenylenediamine catalyzed by laccase .The fluorescence (at λ ex /λ em =464 nm /530 nnm) was enhanced strongly in the presence of organic media . The mechanism of o phenylenediamine oxidation reaction catalyzed by laccase in the presence of L ascorbic acid is discussed .L ascorbic acid is determined in the ethanol, 1,4 dioxane and acetone over the linear range of 4.0×10 -7 ～1.2×10 -4 mol/L, 4.0×10 -7 ～ 8.0×10 -5 mol/L and 4.0×10 -7 ～1.0×10 -4 mol/L with a detection limit of 1.20×10 -8 mol/L,1.19×10 -8 mol/L and 1.24×10 -8 mol/L, respectively. The method has been successfully applied to the simple and rapid determination of L ascorbic acid in pharmaceuticals and milk powder.

SPACE-TIME DISCONTINUOUS GALERKIN METHOD FOR MAXWELL EQUATIONS IN DISPERSIVE MEDIA

In this paper, a unified model for time-dependent Maxwell equations in dispersive media is considered. The space-time DG method developed in [29] is applied to solve the un-derlying problem. Unconditional L2-stability and error estimate of order O？τr＋1＋hk＋1/2？ are obtained when polynomials of degree at most r and k are used for the temporal dis-cretization and spatial discretization respectively. 2-D and 3-D numerical examples are given to validate the theoretical results. Moreover, numerical results show an ultra-convergence of order 2r＋1 in temporal variable t.

Dynamics and near-optimal control in a stochastic rumor propagation model incorporating media coverage and Lévy noise

The appearance of rumors intensifies people’s panic and affects social stability. How to control the spread of rumors has become an important issue which is worth studying. In order to more accurately reflect the actual situation in the real world, a stochastic model incorporating media coverage and Lévy noise is proposed to describe the dynamic process of rumor propagation. By introducing two control strategies of popular science education and media coverage in an emergency event, an near-optimal control problem that minimizes the influence and control cost of rumor propagation is proposed.Sufficient conditions for near-optimal control of the model are established by using a Hamiltonian function. Then the necessary conditions for near-optimal control are obtained by using the Pontryagin maximum principle. Finally, the effect of popular science education, media coverage and Lévy noise on rumor propagation process control is verified by numerical simulation.

Investigation of L1_0 FePt-based soft/hard composite bit-patterned media by micromagnetic simulation

The soft/hard composite patterned media have potential to be the next generation of magnetic recording, but the composing modes of soft and hard materials have not been investigated systematically. L10 FePt-based soft/hard composite patterned media with an anisotropic constant distribution are studied by micromagnetic simulation. Square arrays and hexagonal arrays with various pitch sizes are simulated for two composing types： the soft layer that encloses the hard dots and the soft layer that covers the whole surface. It is found that the soft material can reduce the switching fields of bits effectively for all models. Compared with the first type, the second type of models possess low switching fields, narrow switching field distributions, and high gain factors due to the introduction of inter-bit exchange coupling. Furthermore, the readout waveforms of the second type are not deteriorated by the inter-bit soft layers. Since the recording density of hexagonal arrays are higher than that of square arrays with the same center-to-center distances, the readout waveforrns of hexagonal arrays are a little worse, although other simulation results are similar for these two arrays.

Effect of Growing Media on Growth and Flowering of Different Hyacinth Cultivars （Hyacinthus orientalis L.）

A pot experiment has been conducted in Faculty of Agricultural and Forestry, Lath House of Horticultural Department, School of Plant Production, Duhok University during the growing season 2010-2011. The study consisted of testing the effects of four different growth media （Clay, Loam, Clay ＋ sheep manure （1：1） and Loam ＋ sheep manure （1：1） as volumetric rates on vegetative and flowering growth characters of five different cultivars of Hyacinths plant （Blue Giant, City of Haarlem, Jon Bos, Delf Blue and Fondante）. The experiment was laid out in randomized complete block design （RCBD） of two factors in three replicates. Media mostly affected the parameters studied during the experiment. Early emergence （22.53 days） and flowering （73.13 days） was recorded in medium consisting of loam and sheep manure, while maximum plant height （19.75 cm）, leaves number （6.13）, leaf area （31.47 cm2） were recorded in clay medium. Maximum number of florets plant-l （31.93） and spike length （7.95 cm） were recorded in medium consist of clay and sheep manure. Maximum length of spike stem （9.61 cm） and total chlorophyll percentage （53.45%） were recorded for loam medium. Among the cultivars, some parameters showed significant variation. Early emergence （20.42 days）, maximum plant height （20.35 cm）, leaf area per plant （33.01 cm2） and length of spike stem （15.10 cm） were given by cv. Fondante. Maximum number of florets plantl （35.58） and spike lengths （8.63 cm） were recorded by cv. Blue Giant. High percentage of total chlorophyll （58.15%） was recorded in cv. Jon Bos..

荜茇提取物的抗氧化活性及改善LPS所致大鼠听力损伤的作用研究

目的 探讨荜茇提取物的抗氧化活性及改善LPS所致大鼠听力损伤的作用。方法 测试浓度为0.05~1.0 mg/mL的荜茇提取物对DPPH自由基的清除率;测试浓度为25~500μg/mL荜茇提取物对LPS诱导RAW 264.7细胞分泌NO的抑制作用。随机将24只SD大鼠分成空白对照组、模型组、氢化可的松组和荜茇提取物组,每组6只,空白对照组不造模处理,模型组、氢化可的松组及荜茇提取物组连续鼓室内注射5 mg/mL的LPS 5 d后,模型组生理盐水灌胃,氢化可的松组1.81 mg/kg氢化可的松灌胃,荜茇提取物组按生药量1 g/mL荜茇提取物灌胃,连续灌胃10 d后,测试各组大鼠8、16 kHz ABR反应阈值、耳蜗组织中谷氨酸、MDA、TNF-α、NO因子的表达量,并行耳蜗基底膜铺片观察。结果 荜茇提取物对DPPH自由基清除的IC50为0.505 mg/mL;浓度为25~500μg/mL的荜茇提取物对LPS诱导的RAW264.7细胞过度分泌NO有显著的抑制作用,抑制率的IC50为280.55μg/mL。连续灌胃10 d后,与空白对照组相比,模型组8、16 kHz ABR阈值显著升高,耳蜗组织中谷氨酸、MDA、TNF-α、NO的表达显著升高,SOD含量显著降低;与模型组相比,氢化可的松组和荜茇提取物组8、16 kHz的ABR反应阈值降低(P<0.01),大鼠耳蜗组织谷氨酸、MDA、TNF-α、NO因子表达也显著降低(分别为P<0.05、P<0.01、P<0.001),SOD活力提高(P<0.05)。基底膜铺片结果示,空白组毛细胞无明显缺失,三排外毛细胞纤毛排列整齐,结构完整,无缺失;模型组耳蜗毛细胞大部分明显缺失,并且细胞肿胀明显、结构严重不完整,氢化可的松组及荜茇提取物组耳蜗毛细胞排列较为整齐,毛细胞肿胀缓解。结论 荜茇提取物可能通过抑制耳蜗组织中的谷氨酸、自由基的过度表达以及炎症反应,提高超氧化歧化酶SOD活力,产生良好的改善听力作用。

基于ITS和trnL-F序列碱基差异的繁缕及其近缘种的亲缘关系分析

应用PCR产物直接测序法分析了繁缕〔Stellaria media（L.）Villars〕及其近缘种和鹅肠菜〔Myosoton aquaticum（L.）Moench〕的ITS和trnL-F序列的碱基差异,并以孩儿参〔Pseudostellaria heterophylla（Miq.）Pax〕为外类群构建N-J系统树,分析了这些种类的种间亲缘关系。结果表明,供试的繁缕属（Stellaria L.）种类及鹅肠菜的ITS和trnL-F序列长度分别为521-784和788-951 bp,各有变异位点77和59个,其中信息位点分别为18和11个,种间碱基差异百分率分别为6.5%和3.1%。ITS的碱基组成为A22.1%、T20.9%、G28.5%和C28.5%,G＋C含量57.0%;trnL-F的碱基组成为A 35.9%、T33.7%、G 15.7%和C 14.8%,G＋C含量30.5%。繁缕、雀舌草（S.alsine Grimm）和箐姑草（S.vestita Kurz）的ITS和trnL-F序列一致;鹅肠菜的ITS序列中有4个位点与前述种类不同,但trnL-F序列则相同;中国繁缕（S.chinensis Regel）的ITS和trnL-F序列与孩儿参较相似。在N-J系统树中,鹅肠菜与繁缕、雀舌草和箐姑草聚为一支,表明它们的亲缘关系相对较近,支持将鹅肠菜重新归入繁缕属的分类处理。研究结果显示,ITS和trnL-F序列分析均可用于繁缕及其近缘种的鉴别,且ITS是更为适宜的分子标记。

从中药繁缕中几个黄酮碳苷成分的分离和分析看LC-MS-MS技术的优势与不足

繁缕[Stellaria media(L)Cyr.]为石竹科植物繁缕的茎、叶,具有活血、去瘀、下乳、催生作用,主要含皂苷、黄酮、酚酸、氨基酸等成分[1～3].贵州民间作为降血脂药物应用,效果很好.文献调研表明,其活性成分可能为黄酮苷类化合物[4].……

植物挥发性单萜经土壤载体的化感作用--以三裂叶豚草(Ambrosia trifida L．)为例

植物释放的挥发性单萜在生态系统中起着重要的作用,这些单萜不仅能以空气为载体对其他植物显示直接的化感作用,而且也能以土壤为载体进行间接的化感作用。通过对三裂叶豚草挥发物对植物种子萌发和土壤微生物种群影响及其化学成分的鉴定研究,验证了以单萜类物质为主的三裂叶豚草挥发物可以经土壤载体对其他植物及土壤微生物显示化感效应。还对植物挥发物化学成分鉴定的GC(气相色谱)和GC-MS(气相色谱-质谱联用)方法存在的一些误区进行了澄清,这将有助于对生态系统中植物挥发物化感作用的研究和认识。

鼠李糖乳杆菌发酵生产L-乳酸培养基的优化

对鼠李糖乳杆菌发酵生产L-乳酸的发酵培养基组成进行了研究;通过正交实验得到最佳氮源组合为酵母粉5g/L,蛋白胨10g/L,牛肉膏15g/L;生长因子实验表明,番茄汁和白菜汁的添加量各为10%时,L-乳酸的产量最高;葡萄糖、吐温80、生长因子和氮源的四因素正交实验表明,最佳培养基组成为葡萄糖160g/L,酵母粉5g/L,蛋白胨10g/L,牛肉膏15g/L,吐温801mL/L,番茄汁50mL/L,白菜汁50mL/L。用该培养基发酵所得L-乳酸的产量高达143.6g/L,得率为89.8%。

非水相脂肪酶催化合成L-抗坏血酸棕榈酸酯的研究Ⅰ

对催化合成L 抗坏血酸棕榈酸酯反应的脂肪酶 (NOVO435、MML、LIPOLASE、PPL)和反应介质进行比较 ,得出最佳酶种为NOVO435 ,最佳介质为叔戊醇 ;同时对影响合成L 抗坏血酸棕榈酸酯反应的初速度的因素 (转速、温度、水分含量、酶浓度和底物浓度 )进行了探讨 ,确定了最适反应条件 :转速为 2 0 0r/min ,温度为 5 5℃ ,水分含量为 0 ,酶浓度为 12 5 %。