The effects of oxygen partial pressure on the optical absorption edge and the UV emission energy of ZnO films

The optical absorption edge and ultraviolet (UV) emission energy of ZnO films deposited by direct current (DC) reactive magnetron sputtering at room temperature have been investigated. With the oxygen ratio increasing, the structure of films changes from zinc and zinc oxide coexisting phase to single-phase ZnO and finally to the highly (002) orientation. Both the grain size and the stress of ZnO film vary with the oxygen partial pressure. Upon increasing the oxygen partial pressure in the growing ambient, the visible emission in the room-temperature photoluminescence spectra was suppressed without sacrificing the band-edge emission intensity in the ultraviolet region. The peaks of photoluminescence spectra were located at 3.06---3.15 eV. From optical transmittance spectra of ZnO films, the optical band gap edge was observed to shift towards shorter wavelength with the increase of oxygen partial pressure.

影响圆叶牵牛(Ipomoea purpurea)花中花青素含量的因子研究

表型是基因型和环境共同作用的结果，环境对物种进化起到了至关重要的作用。虽然人们已经知道环境因子会影响植物花青素的最终含量，但这样的影响是如何在自然环境中进行的仍是未知。较之以前泛泛研究经济作物或模式植物的花青素总含量与人工环境变量的关系的工作，本文探讨环境变化对半野生的圆叶牵牛自然状态下不同基因型植株、不同花青素的影响。 65株取自全国各地包括3种颜色8种基因型的圆叶牵牛被分别种到了温室和室外，温室32株，室外35株，用高效液相 (HPLC) 的方法检测盛花期 (07年9月-10月) 圆叶牵牛花中花青素的含量，同时每天分早中晚采集3次温室和室外的环境数据-照度、紫外线强度、温度、湿度。记录每朵花着生高度、朝向、当天植株开花数、植株根茎、植株生长天数等个体信息。 通过保留时间、紫外-可见吸收光谱数据、质谱数据以及参考文献确定了圆叶牵牛花瓣中主要的5种花青素，包括三个矢车菊素 (CY) 和两个天竺葵素 (PG)，根据它们所含的咖啡酸和葡萄糖基的个数将它们简写成CY3C4G、CY2C4G、CY3C5G、PG2C4G、PG3C5G。CY2C4G和CY3C4G仅在蓝紫色花中大量存在，PG2C4G及PG3C5G仅在粉色花中大量存在，CY3C5G在两种颜色的圆叶牵牛花中均有存在。 温室和室外的四个环境因子有显著差异，平均照度室外为温室的3.06倍，平均紫外线强度为温室的5.39倍。Z 检验表明，蓝紫色花中的CY3C5G在温室内外没有显著差异 (P=0.3070)，而温室内的CY2C4G (P<0.0001) 和CY3C4G (P<0.0001) 含量明显的低于室外，粉花中CY3C5G和PG3C5G在温室 (P=0.4533) 和室外 (P=0.9577) 没有显著差异，PG2C4G在温室内含量明显 (P=0.0003) 低于室外。 通过Kruskal- Wallis 检验,不同基因型植株各种花青素的相对含量显著不同 (P<0.0001)。室外不同基因型植株的花青素绝对含量显著不同 (P<0.0001)。温室不同基因型植株中，CY2C4G (P=0.0224) 和CY3C4G (P=0.0017) 的绝对含量显著不同，显著性比室外的低些。CY3C5G不同基因型的绝对含量有差异，但是差异不显著 (P=0.0633)。基因型对植株中各个花青素相对含量的影响是尤其显著的，基因型对于花青素绝对含量的影响，可能是基因型直接作用和不同基因型对环境差异的不同响应两方面造成的，所以在环境变异稍大的条件下，基因型更加能显示出它对花青素的含量的影响。 植株的生长天数与粉色圆叶牵牛的PG2C4G、PG3C5G以及蓝紫色圆叶牵牛的三个花青素呈一定的正相关，当天开花数对粉色花的PG3C5G以及蓝紫色花的三个花青素呈负相关，花的朝向 (北-东-南-西-北 对应数值为0-90-180-90-0)，对粉花的PG2C4G以及蓝紫花的CY2C4G和CY3C4G 呈正相关，植株大小对粉花的PG2C4G、PG3C5G以及蓝紫花的CY3C5G呈负相关。花所着生的高度对两种颜色花的影响是不同的，与蓝紫花的三个花色素呈负相关，对于粉色的PG2C4G、CY3C5G呈正相关。

玉米的单倍体育种及基因转化的研究

玉米的单倍体育种，是利用花药培养或孤雌生殖产生单倍体后，进行人工或自然加倍，迅速获得稳定的新品种的育种方法。单倍体育种可以缩短育种时间，单倍体培养体系如果作为转基因的受体，可保证外源基因在后代中稳定遗传，而不发生分离。因此，玉米单倍体育种无论在实践中还是在理论研究方面都具有重大的意义。 本文针对玉米花药培养中长期以来未能解决的诱导频率低、基因型之间差异大、小苗移栽不容易成活等问题，重点探讨了各种因素对玉米花药培养的影响。结果表明：不同基因型之间的诱导频率差异明显，杂交种的诱导频率比纯系高，并选择出诱导频率高达20%的材料“中0198”;接种时花药中的花粉处于单核中期时，其诱导频率最高;采用液体培养基比采用固体培养基诱导频率提高一倍;培养基中加入0.5%的活性炭，可使诱导频率由5.25%提高到9.35%;15%的蔗糖浓度对玉米的花药培养是最适宜的，培养2周后，将培养基的蔗糖浓度从15%调整为10%，将明显提高诱导频率;培养基中高浓度的KT和低浓度的BA有利于诱导体细胞胚的发生，而低浓度的KT和高浓度的BA有利于诱导芽的发生;接种前将花药在4℃条件下进行低温预处理，可将诱导频率从3.13%提高到11.71%;培养基中添加2 mg/l的多效唑，可有效地促进小苗的生根;再生植株于冬季拿到海南种植，可明显提高移栽的成活率。 在玉米孤雌生殖的实验中，将未受粉的玉米雌穗接种在成份为N6 + 2,4-D 1mg/L + NAA 1mg/L + BA 1mg/L + CH 200mg/L + colchicine 2 mg/L + sucrose 5% + agar 0.7% 的培养基上。第一轮实验共接种了三个材料的26个雌穗（约3900个未受精的子房）。每种材料均有单性结实，诱导频率由高到低分别3.06%，2.29%，1.90%。直接获得了5株再生植株，通过染色体检查，发现其中3株为单倍体（n=10），另外2株为二倍体。移栽到土壤中后，有4株成活，其中一株二倍体植株能够正常开花、结实。得到的种子播种于实验田中，表现整齐一致，有纯系的特征，而且出现了2株白化苗。通过石蜡切片初步观察了孤雌生殖的胚胎发生过程，发现胚胎发生是从胚囊里的单倍体细胞起源的。第二、三轮实验又接种了10个基因型的玉米材料，证实了上述结果。 外源基因转导是利用生物技术进行玉米育种的一个有效途径。本文首次尝试了用离体子房注射法对玉米进行基因转化。首先构建了含有开花促进因子基因FPF1及植物选择标记抗除草剂基因pat的植物表达载体pFBR，采用离体注射培养法，取授粉24小时后的玉米雌穗，剥去苞叶，在超净工作台进行微量注射，然后切成小块接种在培养基上，在光照培养箱内培养，3-4周可直接获得种子或小植株。种子萌发后进行植株抗性筛选和分子检测，共注射了3个品种的47个雌穗（约16450个子房）得到再生植株109株，其中经PPT筛选有抗性的植株为23株，占再生植株的21.1%。经PCR检测，13株植株有阳性反应。但Southern杂交检测有杂带出现。出现杂带的原因、RNA水平的分子检测、转基因后代T1代的分子检测和早开花农艺性状的观察，由于时间关系没有完成，还需要进一步的实验。实验初步证明了离体子房注射法对玉米进行基因转化的可行性，而且与田间注射法相比，此方法具有省力省时，容易控制污染，转化效率提高的优点, 克服了玉米培养再生植株受基因型限制的困境, 将为玉米分子育种的基因工程提供更易行的手段。 同时，也为子房较大的其它植物的基因转化提供了方法。

Cryopreservation of cynomolgus monkey (Macaca fascicularis) spermatozoa in a chemically defined extender

Aim: To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods: Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant. The effects of glycerol concentration (1%,3%, 5%, 10% and 15% [v/v]) and its equilibration time (10 min, 30 min, 60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity. Results: The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P < 0.05) for 5% glycerol (42.95 +/- 2.55 and 50.39 +/- 2.42, respectively) than those of the other groups (1%: 19.19 +/- 3.22 and 24.84 +/- 3.64; 3%: 34.23 +/- 3.43 and 41.37 +/- 3.42; 10%: 15.68 +/- 2.36 and 21.39 +/- 3.14; 15%: 7.47 +/- 1.44 and 12.90 +/- 2.18). The parameters for 30 min equilibration (42.95 2.55 and 50.39 2.42) were better (P < 0.05) than those of the other groups (10 min: 31.33 +/- 3.06 and 38. 98 +/- 3.31; 60 min: 32.49 +/- 3.86 and 40.01 +/- 4.18; 90 min: 31.16 +/- 3.66 and 38.30 +/- 3.78). Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity. Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender, which is related to the concentration and the equilibration time of glycerol.

Hybrid cytomegalovirus-U6 promoter-based plasmid vectors improve efficiency of RNA interference in zebrafish

Short hairpin RNA (shRNA) directed by RNA polymerase III (Pol III) or Pol II promoter was shown to be capable of silencing gene expression, which should permit analyses of gene functions or as a potential therapeutic tool. However, the inhibitory effect of shRNA remains problematic in fish. We demonstrated that silencing efficiency by shRNA produced from the hybrid construct composed of the CMV enhancer or entire CMV promoter placed immediately upstream of a U6 promoter. When tested the exogenous gene, silencing of an enhanced green fluorescent protein (EGFP) target gene was 89.18 +/- 5.06% for CMVE-U6 promoter group and 88.26 +/- 6.46% for CMV-U6 promoter group. To test the hybrid promoters driving shRNA efficiency against an endogenous gene, we used shRNA against no tail (NTL) gene. When vectorized in the zebrafish, the hybrid constructs strongly repressed NTL gene expression. The NTL phenotype occupied 52.09 +/- 3.06% and 51.56 +/- 3.68% for CMVE-U6 promoter and CMV-U6 promoter groups, respectively. The NTL gene expression reduced 82.17 +/- 2.96% for CMVE-U6 promoter group and 83.06 +/- 2.38% for CMV-U6 promoter group. We concluded that the CMV enhancer or entire CMV promoter locating upstream of the U6-promoter could significantly improve inhibitory effect induced by the shRNA for both exogenous and endogenous genes compared with the CMV promoter or U6 promoter alone. In contrast, the two hybrid promoter constructs had similar effects on driving shRNA.

从径向生长量分析红松幼树生长光需求

该文调查了20年前在辽东山区次生林林冠下栽植红松幼苗而长成的群落,分析了红松在群落中的地位,检测林冠下栽植红松的成效,并以基盘分析20年期间红松径向生长规律,从而探讨首次透光伐的适宜时间。结果表明:20年后红松植株高均小于4 m,大于3 m的植株仅占13.9%,平均高为1.8 m,树高年平均增长量为0.078 m/a;大部分红松仍位于灌木层,这说明在无法保证光照的环境中红松生长十分缓慢,应实行透光伐。红松径向生长规律为:先有一个2~3年的缓慢生长过程,随后加速增长并持续一段时间,然后锐减并稳定在一个极低值;林冠下栽植红松后4~12年是红松快速生长时期,这9年期间平均径向生长量为3.06 mm/a;第8年平均径向生长量达到最大值,为3.45 mm/a;第13年红松径向生长量急剧下降,在1.32~1.83 mm/a之间。根据受压判断公式测得在12年后应进行首次透光伐。

黄土高原沟坡地土地生产力评价的指标体系与评价方法

通过对渭北黄土高原地区沟坡地土壤理化性质的分析和对当地社会经济状况的调查研究,应用层次分析法对沟坡地上地自然生产力和现实生产力进行了分析和评价。在分析过程中,把当地主要造林树种根系垂直分布特征及其根系抗旱性特性纳入了分析评价体系。结果表明,嘴头村和西坡村不同树种沟坡地上刺槐(Robinia pseudoacacia)的自然生产力属于中等稍微偏上水平,而山杏(Prunus armeniacia var.ansu)、油松(Pinus tabulaeformis)和侧柏(Platycladus orientalis)的自然生产力水平则较低。两地沟坡地上的现实生产力计算结果则证明刺槐和山杏两个树种表现出了较高的水平,具有较好的发展前途;而油松和侧柏的现实生产力水平则较低,其发展推广受到了限制。群众对沟坡开发治理的态度和对开发方案的认可对沟坡开发的成功起到了重要作用。

Crystallization behavior of a novel poly(aryl ether ketone): PEDEKmK

Isothermal melt and cold crystallization kinetics of PEDEKmK linked by meta-phenyl and biphenyl were investigated by differential scanning calorimetry in two temperature regions. Avrami analysis is used to describe the primary stages of the melt and cold crystallization, with exponent n = 2 and n = 4, respectively. The activation energies are -118 kJ/mol and 510 kJ/mol for crystallization from the melt and the glassy states, respectively. The equilibrium melting point T-m(0) is estimated to be 309 degrees C by using the Hoffman-Weeks approach, which compares favorably with determination from the Thomson-Gibbs method. The lateral and end surface free energies derived from the Lauritzen-Hoffman spherulitic growth rate equation are sigma = 8.45 erg/cm(2) and sigma(e) = 45.17 erg/cm(2), respectively. The work of chain folding q is determined as 3.06 kcal/mol. These observed crystallization characteristics of PEDEKmK are compared with those of the other members of poly(aryl ether ketone) family. (C) 1997 John Wiley & Sons, Inc.

中华绒螯蟹（Eriocheir sinensis）Peroxiredoxin 6和Thioredoxin1基因的克隆及表达

中华绒螯蟹是我国重要的水产经济动物，近年来养殖规模不断扩大，产量持续增加。但是，伴随着养殖规模的扩大，养殖环境也日益恶化并导致了大量疾病的发生，严重制约了中华绒螯蟹养殖业的健康发展。因此，疾病预防和控制对中华绒螯蟹养殖业的可持续发展具有举足轻重的作用。与其他无脊椎动物一样，中华绒螯蟹的免疫系统没有免疫球蛋白和淋巴细胞，而是依靠由细胞免疫和体液免疫构成的固有免疫系统来对病原进行识别和清除。中华绒螯蟹的固有免疫机制的研究有助于推动中华绒螯蟹病害防治工作的开展。 本研究采用大规模EST测序方法，结合末端快速扩增（rapid amplification of cDNA ends，RACE）技术从中华绒螯蟹血淋巴中克隆到了过氧化物还原酶（peroxiredoxin，EsPrx6）和硫氧还蛋白（thioredoxin，EsTrx1）基因的cDNA 全长序列；采用实时荧光定量PCR 技术检测了这两个基因在健康个体中表达的组织分布情况以及鳗弧菌刺激后血淋巴细胞中的时序表达规律；同时，将这两个基因的编码区克隆到pET 系列载体，并在大肠杆菌中实现了重组表达，并进行了体外活性检测。 过氧化物还原酶是一个抗氧化蛋白超家族，在保护机体免受活性氧（reactive oxygen species，ROS）的伤害中发挥着重要作用。中华绒螯蟹Prx6（EsPrx6） 基因的cDNA 全长为1076 bp，5` UTR（untranslated region，UTR） 为69 bp，3` UTR 为347 bp，开放阅读框（open reading frame，ORF）为660 bp，编码219 个氨基酸的蛋白。mRNA 3`-端具有多聚腺苷酸加尾信号（polyadenylation signal）AATAAA 和polyA 尾巴。EsPrx6 的预测分子量为 24 kDa，理论等电点为6.21，具有一个保守的Prx 结构域、一个AhpC 结构域和过氧化物酶催化活性中心PVCTTE，表明EsPrx6 属于1-Cys 型Prx。在所检测的组织中均有EsPrx6 的表达，其中以肝胰腺表达量最高，为血淋巴细胞中表达量的17.4 倍。鳗弧菌刺激后，血淋巴细胞中EsPrx6 的表达下降，到12 h 时，实验组显著低于对照组（P<0.05）；随时间推移，表达水平逐渐回升，但在整个实验期间，都没有恢复到起始水平。将EsPrx6 进行体外重组并在大肠杆菌E. coli BL21（DE3）中实现表达，重组EsPrx6 具有预期的抗氧化活性和过氧化物酶活性，其中抗氧化活力为14.69 U/mg 蛋白，高于相同条件下GSH 的抗氧化力（P<0.05），过氧化物酶活力为23.46 U/mg 蛋白。结果表明，EsPrx6 作为一种重要的抗氧化剂，在中华绒螯蟹抵御ROS 可能引起的氧化损伤方面具有重要作用。 硫氧还蛋白是广泛存在于生物体内的一种具有硫醇依赖性的具有还原活性的蛋白。中华绒螯蟹Trx1（EsTrx1）基因的cDNA 全长为641 bp，5` UTR 为17 bp，3` UTR 为306 bp，开放阅读框为318 bp，编码105 个氨基酸。EsTrx1 的预测分子量为12.2 kDa，理论等电点为4.8。EsTrx1 不含信号肽，其氨基酸序列与其他动物的Trx1s 具有高度相似性，如与地中海黄蝎的Trx1 相似度达到73%；而与其他物种Trx2 的同源性很低，相似度仅为14.3-22.8%，表明EsTrx1 属于Trx1 亚族。实时荧光定量PCR 检测发现，EsTrx1 在鳃、性腺、肝胰腺、肌肉、心脏和血淋巴细胞中都有表达。血淋巴细胞中EsTrx1 mRNA 的表达量在菌刺激后上升，刺激后6 h，实验组表达量显著高于对照组和空白组（P<0.05），然后逐渐恢复到刺激前水平。为进一步探讨其生物学功能，将EsTrx1 进行体外重组并在大肠杆菌E. coli BL21（DE3）得到表达，重组EsTrx1 具有预期的氧化还原调节活性，抗氧化活力为3.06 U/mg，且抗氧化活力高于GSH（P<0.05）。rEsTrx1 的二硫键还原活力为5.03，低于凡纳滨对虾的二硫键还原活力（10.44），接近于大肠杆菌（4.93），小牛胸腺（6.50）和小牛肝脏（5.09），而高于鲍鱼Trx2（1.83）活力。结果表明，EsTrx1 在生理条件下能够作为一种重要的抗氧化剂，参与对细菌感染的免疫应答反应。

Density-dependent effects on seston dynamics and rates of filtering and biodeposition of the suspension-cultured scallop Chlamys farreri in a eutrophic bay (northern China): An experimental study in semi-in situ flow-through systems

Effects of stocking density on seston dynamics and filtering and biodeposition by the suspension-cultured Zhikong scallop Chlamys farreri Jones et Preston in a eutrophic bay (Sishili Bay, northern China), were determined in a 3-month semi-field experiment with continuous flow-through seawater from the bay. Results showed that the presence of the scallops could strongly decrease seston and chlorophyll a concentrations in the water column. Moreover, in a limited water column, increasing scallop density could cause seston depletion due to scallop's filtering and biodeposition process, and impair scallop growth. Both filtration rate and biodeposition rate of C. farreri showed significant negative correlation with their density and positive relationship with seston concentration. Calculation predicts that the daily removal of suspended matter from water column by the scallops in Sishili Bay ecosystem can be as high as 45% of the total suspended matter; and the daily production of biodeposits by the scallops in early summer in farming zone may amount to 7.78 g m(-2), with daily C, N and P biodeposition rates of 3.06 x 10(-1), 3.86 x 10(-2) and 9.80 x 10(-3) g m(-2), respectively. The filtering and biodeposition by suspension-cultured scallops could substantially enhance the deposition of total suspended particulate material, suppress accumulation of particulate organic matter in water column, and increase the flux of C, N and P to benthos, strongly enhancing pelagic-benthic coupling. It was suggested that the filtering-biodeposition process by intensively suspension-cultured bivalve filter-feeders could exert strong top-down control on phytoplankton biomass and other suspended particulate material in coastal ecosystems. This study also indicated that commercially suspension-cultured bivalves may simultaneously and potentially aid in mitigating eutrophication pressures on coastal ecosystems subject to anthropogenic N and P loadings, serving as a eutrophic-environment bioremediator. The ecological services (e.g. filtering capacity, top-down control, and benthic-pelagic coupling) functioned by extractive bivalve aquaculture should be emphasized in coastal ecosystems. (c) 2005 Elsevier B.V. All rights reserved.

Investigation of the spectroscopic properties of (Y0.92-xLa0.08Ndx)(2)O-3 transparent ceramics

The spectroscopic properties of (Y0.92-xLa0.08Ndx)(2)O-3 transparent ceramics were investigated. According to three intensity parameters (Omega(2),Omega(4),Omega(6)) fitted by the Judd-Ofelt theory, the spectroscopic quality parameter (X-Nd), branching ratio (beta(J,J')), and quantum efficiency (eta) of Nd3+ were determined. It was found that X-Nd of the host, owing to the additive La2O3, was decreased from 1.6 to 0.46; thus beta(J,11/2) was increased from 46% to 56.82%. A figure of merit of the specimens was discussed and compared with Nd:YAG transparent ceramic. (c) 2007 Optical Society of America.

Judd-Ofelt analysis of spectra and experimental evaluation of laser performance of Tm3+ doped Lu2SiO5 crystal

This paper reports that the TM3+:Lu2SiO5 (Tm:LSO) crystal is grown by Czochralski technique. The room-temperature absorption spectra of Tm:LSO crystal are measured on a b-cut sample with 4 at.% thulium. According to the obtained Judd-Ofelt intensity parameters Omega(2)=9.3155 x 10(-20) cm(2), Omega(4)=8.4103 x 10(-20) cm(2), Omega(6)=1.5908 x 10(-20) cm(2), the fluorescence lifetime is calculated to be 2.03 ms for F-3(4) -> H-3(6) transition, and the integrated emission cross section is 5.81 x 10(-18) cm(2). Room-temperature laser action near 2 mu m under diode pumping is experimentally evaluated in Tm:LSO. An optical-optical conversion efficiency of 9.1% and a slope efficiency of 16.2% are obtained with continuous-wave maximum output power of 0.67 W. The emission wavelengths of Tm:LSO laser are centred around 2.06 mu m with spectral bandwidth of similar to 13.6 nm.

Anti Human Immunodeficiency Virus-1 (HIV-1) Agents 3. Synthesis and in Vitro Anti-HIV-1 Activity of Some N-Arylsulfonylindoles

In order to find compounds with superior anti human immunodeficiency virus type 1 (HIV-1) activity, twelve simple N-arylsulfonylindoles (3a-1) were synthesized and preliminarily evaluated as HIV-1 inhibitors in vitro for the first time. Several compounds

1.3微米InGaAs/GaAs自组织量子点激光器材料及生长该材料的方法

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