水母雪莲愈伤组织超低温保存条件的初探

初步研究了水母雪莲愈伤组织的超低温保存方法. 结果表明，预培养、保护剂、预处理、冰冻后处理对愈伤组织存活率都有一定影响. 水母雪莲愈伤组织预培养基为添加5%二甲基亚砜的MS培养基，优化的冰冻保护剂是15%二甲基亚砜+15%乙二醇+30%甘油的0.4 mol/L蔗糖液，冰冻保护剂的预处理温度是15℃，时间为10 min，解冻温度25~35℃；在25℃水浴中用含1.2 mol/L蔗糖的MS溶液反复洗3次，每次10 min. 用TTC法测定细胞存活率可达58.5%.     

光质对玛咖愈伤组织生长、分化的影响

研究了在组织培养过程中光质对玛咖愈伤组织生长、分化及细胞内糖代谢关键酶的影响. 在红光、黄光和白光下培养25 d, 玛咖愈伤组织的干重明显高于在绿光和蓝光下. 在分化培养基上,红光、黄光和白光条件下玛咖愈伤组织的出芽率达78%~82%,而在绿光和蓝光下出芽率几乎为0. 进一步研究表明,红光、黄光和白光条件下糖代谢中3种关键酶(葡萄糖-6-磷酸酶、己糖激酶、苹果酸脱氢酶)的活性明显高于绿光和蓝光条件下,与愈伤组织生长、分化情况相关联,说明细胞内的糖代谢受光质调节并参与了对愈伤组织生长和分化的调节.     

藏红花胚性愈伤组织的发生及其调控

为提高藏红花胚性愈伤组织的繁殖系数和出芽率,促进其生长和分化,以建立藏红花离体快繁体系,解决藏红花资源短缺问题,研究了藏红花胚性愈伤组织的发生及其调控. 结果表明,获得的藏红花球茎1细胞系具有良好的胚性愈伤组织发生能力. 胚性愈伤组织生长的优化条件为：在添加3.0 mg/L 6-BA, 0.25 mg/L NAA和400 mg/L CH的B5固体培养基上,22℃下全时暗培养25 d,繁殖系数达到9 g/g. 胚性愈伤组织出芽的优化条件为：在添加3.0 mg/L 6-BA, 0.25 mg/L NAA和400 mg/L CH的1/2 B5固体培养基上,在22℃及光照强度31.74 mmol/(m2×s)条件下,每天光照10 h,暗培养14 h,培养45 d出芽率达到44.7%,高于国外报道的20%.     

XinanI 介导的草甘膦高抗转基因水稻的研究

通过农杆菌介导的转化方法,将携带草甘膦抗性基因 xinanI 的农杆菌分别侵染粳稻品种豫农粳与方欣4号愈伤组织,通过2轮2 mmol/L 草甘膦筛选获得抗性愈伤组织,再经过诱导和分化得到了转基因水稻幼苗.对转基因幼苗进行 xinanI 基因特异性 PCR 分析和草甘膦抗性筛选,结果表明,豫农粳与方欣4号抗性愈伤组织分化的幼苗的 PCR 阳性率分别是75.1%和72.0%,草甘膦抗性筛选阳性率分别为52.7%和49.4%.进一步对转基因植株进行抗性分析表明,草甘膦抗性基因 xinanI 在水稻中可以高效表达,并赋予水稻高水平草甘膦抗性,T0代转基因植株经1.6%草甘膦溶液处理后仍然可以正常生长发育.     

肉苁蓉愈伤组织的超低温保藏方法

提出了一个优化的简单的超低温保藏方法,成功地运用于肉苁蓉愈伤组织的低温保藏. 为了获得最佳的实验结果,肉苁蓉愈伤组织首先在添加了6%二甲亚砜的B5培养基中进行预培养,然后用玻璃化保护剂在25℃处理20 min,最后投入液氮中进行冷冻. 玻璃化保护剂的成分为30%(j)甘油+15%(j)乙二醇+10%(j)二甲亚砜+0.5 mol/L蔗糖. 冷冻后的愈伤组织在30℃的水浴中迅速解冻,接着用25℃的1.0 mol/L蔗糖溶液洗净愈伤组织上附着的玻璃化保护剂,最后在B5培养基上对愈伤组织进行恢复性培养. 经过上述冻存处理的肉苁蓉愈伤组织存活率可达86％. 恢复培养5个月后,愈伤组织中苯乙醇糖甙类化合物的含量和产量分别达到冷冻前的97%和95%.     

XinanⅠ介导的草甘膦高抗转基因水稻的研究

通过农杆菌介导的转化方法,将携带草甘膦抗性基因xinanⅠ的农杆菌分别侵染粳稻品种豫农粳与方欣4号愈伤组织,通过2轮2 mmol/L草甘膦筛选获得抗性愈伤组织,再经过诱导和分化得到了转基因水稻幼苗。对转基因幼苗进行xinanⅠ基因特异性PCR分析和草甘膦抗性筛选,结果表明,豫农粳与方欣4号抗性愈伤组织分化的幼苗的PCR阳性率分别是75.1%和72.0%,草甘膦抗性筛选阳性率分别为52.7%和49.4%。进一步对转基因植株进行抗性分析表明,草甘膦抗性基因xinanⅠ在水稻中可以高效表达,并赋予水稻高水平草甘膦抗性,T0代转基因植株经1.6%草甘膦溶液处理后仍然可以正常生长发育。     

苦参愈伤组织诱导及其杀虫抑菌生物活性测定

通过以苦参越冬芽、茎、子叶和幼叶为外植体诱导愈伤组织，四者在合适的培养基上均能诱导出愈伤组织，幼叶和子叶易于诱导愈伤组织。苦参叶和子叶诱导的愈伤组织处理淡色库蚊的死亡率为100％，处理桃蚜的死亡率分别为81．01％和85．42％，高于其他愈伤组织的活性；各愈伤组织处理朱砂叶螨的死亡率均达到了95％以上，与种子提取物的活性没有显著差异。只有子叶诱导的愈伤组织对油菜菌核病菌表现出了抑制作用，各愈伤组织对小麦赤霉病菌和黄瓜灰霉病菌均未表现出明显的活性，显著低于苦参种子提取物的活性。     

漆树组织培养技术研究初报

本文报道了从外植体诱导愈伤组织再分化出芽和根的试验。     

厌氧光生物转盘-好氧生物膜久理偶氮染料废水

利用厌氧光生物转盘-好氧移动床膜生物反应器处理偶氮染料废水,探讨了染料浓度、光照时间、供氧条件、硫酸盐浓度4个操作条件对组合:亡艺处理效果的影响.实验结果表明,厌氧光生物转盘对染料废水的脱色和COD去除起主要作用,当光生物转盘连续光照时间为12 h/d,废水中染料质量浓度为100 mg/L,HRT为5 h时,光生物转盘的脱色率达90%左右,COD去除率达70%左右.经过后续好氧移动床处理,厌氧出水中的有毒芳香化合物得到有效降解,系统总COD去除率达90%以上.     

柴胡愈伤组织提取物抗肝癌作用的基因表达研究

目的:对柴胡的愈伤组织中有效成分进行检测,研究柴胡愈伤组织提取物促进肝癌细胞凋亡相关基因的差异表达情况。方法:对柴胡愈伤组织提取物(BSW-ws)进行高效液相检测,分析其有效成分;再使用柴胡愈伤组织提取物对肝癌细胞SMMC-7221给药,经Realtime-PCR实验检测凋亡相关基因的表达情况。结果:(1)分析高效液相检测结果可确定柴胡愈伤组织提取物中含有有效成分柴胡皂苷d;(2)Realtime-PCR试验结果表明与内参基因β-actin相比:Bcl-2表达量下调,Bcl-2表达上调,Bcl-2/Bcl-2比率上调,Caspase 3、Caspase 8、Caspase 9表达均上调。结论:柴胡愈伤组织提取物BSW-ws中含有有效成分为柴胡皂苷d,并且柴胡愈伤组织提取物BSW-ws促进了凋亡相关基因的表达,进而促进肝癌细胞SMMC-7221的凋亡。     

不同环境温度下混凝土箱梁的温度分布及演化规律

通过考虑不同地域、季节、温度时段大体积混凝土内外温差、表面与环境温差,探讨了32 m单箱单室预应力混凝土箱梁的温度场分布的变化以及两类温差的变化规律,采用midas软件模拟了环境温度变化在混凝土箱梁中产生的效应,初步探明了当环境发生较大变化时两类温差的演变特性.研究结果表明,当昼夜温差大于10℃时,混凝土内外温差、表面与环境温差可发生较显著的变化.根据模拟结果,设计了基于环境条件变化特征的温度测点设置方案,揭示了不同环境下混凝土箱梁的温度场分布及演化规律.     

Browning-associated mechanisms of resistance to insects in corn callus tissue

Callus of the fungus- and insect-resistant corn inbred, Mp313E, of differing ages and degrees of brownness was tested for effects on neonate larvae of the corn earworm,Helicoverpa zea. Older, browner, 8-week-old callus caused significantly higher mortality ofH. zea after two days compared to larvae fed 5-week-old callus (brown or not) or pinto bean diet. Larvae fed on the 5-week-old callus were significantly smaller after nine days compared to those fed on nonbrown callus of the same age. Ferulic acid,p-coumaric acid, and sinapic acid, corn allelochemicals associated with cell walls, were oxidized (produced a brown product) up to 10-fold more rapidly by peroxidase preparations of the brown callus compared to nonbrown callus. Peroxidase isozymes from both types of brown callus separated by conventional gel electrophoresis and isoelectric focusing showed more intense anodic/acidic bands compared to peroxidase isozymes separated from the nonbrown callus. Some additional peroxidase isozymes were also present in the brown callus and were able to oxidize ferulic acid. Conventional extraction techniques for phenolic acids indicated free ferulic acid levels were similar for same-age callus, but somewhat less for older callus; no freep-coumaric acid was detected. For esterified and insoluble-bound phenolic content, the level ofp-coumaric acid was higher than that of ferulic acid and was somewhat greater in insoluble-bound fractions for the old callus compared to the younger callus. Color ratings of aqueous extracts and phenolic acid extract residues indicated much brown material remained, which was proportional in color to the original material. The differential insect response to, and peroxidase activity of, brown vs. nonbrown callus were similar to results previously noted for brown pericarps of corn compared to nonbrown pericarps. This information suggests the peroxidases are contributing to the browning through oxidation of phenolic acids and thereby enhancing resistance to insects.     

超声波对固定化辣根过氧化物酶活性影响研究

为了研究超声波对固定化酶活性的影响,以固定化辣根过氧化物酶为对象,研究了不同超声波处理条件(超声功率,超声时间)以及超声条件下催化体系的pH、温度对固定化酶活性的作用。同时对超声波处理后固定化酶活的重复利用性进行测定。结果表明,超声波处理对提高固定化酶在高温、强酸碱条件下催化活性有一定帮助,最佳处理条件为:超声波功率50 W,超声时间30 min,pH 8,温度35℃,在此条件下,与未经超声波处理相比,固定化酶活性提高了17.6%,固定化酶重复利用性增强,经7次使用后,固定化酶催化活性是未经处理的1.8倍。     

乳胶气球浮力变化分析与垂直运动轨迹模拟

基于理想气体状态方程,对乳胶气球的浮力进行计算推导,剖析气球内外气压差和昼夜浮升气体温度差对乳胶气球浮力的影响,并进一步探索中性浮力高度与浮重比的关系。通过建立几何模型、大气模型和动力学模型,利用开发的算法,结合施放试验数据,对乳胶气球升空过程中的垂直运动轨迹进行模拟预测。结果表明,当阻力系数为0.45时,模拟预测结果与试验测试结果的吻合性较好。     

Nocturnal Light Pollution Induces Weight Gain in Mice and Reshapes the Structure,Functions, and Interactions of Their Colonic Microbiota

In mammals, the daily variation in the ecology of the intestinal microbiota is tightly coupled to the circadian rhythm of the host. On the other hand, a close correlation between increased body weight and light pollution at night has been reported in humans and animal models. However, the mechanisms underlying such weight gain in response to light contamination at night remain elusive. In the present study, we tested the hypothesis that dim light pollution at night alters the colonic microbiota of mice, which could correlate with weight gain in the animals. By developing an experimental protocol using a mouse model that mimics light contamination at night in urban residences (dLAN, dim light at night), we found that mice exposed to dLAN showed a significant weight gain compared with mice exposed to control standard light/dark (LD) photoperiod. To identify possible changes in the microbiota, we sampled two stages from the resting period of the circadian cycle of mice (ZT0 and ZT10) and evaluated them by high-throughput sequencing technology. Our results indicated that microbial diversity significantly differed between ZT0 and ZT10 in both LD and dLAN samples and that dLAN treatment impacted the taxonomic composition, functions, and interactions of mouse colonic microbiota. Together, these results show that bacterial taxa and microbial metabolic pathways might be involved with the mechanisms underlying weight gain in mice subjected to light contamination at night.     

Surface modification of poly(ethylene terephthalate) fiber by excimer light

Changes in the surface topography and chemical structure on the surfaces of poly(ethylene terephthalate) (PET) fibers and films caused by the irradiation using an excimer laser beam and excimer lamp light were monitored. The SEM (scanning electron microscopy) observation suggests that a wavy shape was produced by irradiation with the excimer laser beam, while such a wavy shape was not observed when the excimer lamp light was used. The XPS (X-ray photoelectron spectroscopy) analysis of the fiber surface suggests that the O/C intensity ratio was reduced by irradiation using the laser beam, whereas this ratio gradually increased with irradiation with the lamp light. This difference is attributed to the difference in the number of photons in the laser beam, which was much higher than that in the lamp light, although the laser beam and lamp light had the same wavelength and energy. As for wettability to water, the contact angle was smallest for PET irradiated by the excimer lamp light. For adhesion studies, the PET fabric was first coated with an epoxy acrylate solution, irradiated with excimer light, dipped into RFL (resorcinol-formaldehyde-latex) adhesive, and the peel strength to rubber sheet was examined. When the irradiation by the excimer laser beam was compared with that with the excimer lamp light, the laser irradiation showed a good adhesion property even for rubber vulcanization carried out for a long time at high temperature.     

Grain-Boundary Characteristics and Their Influence on the Electrical Resistance of Barium Titanate Ceramics

The integral and spectral cathodoluminescence (CL) properties of grain-boundary zones in positive-temperature-coefficient-type barium titanate ceramics were investigated with respect to typical sintering parameters in the spectral range 300 to 1800 nm at room temperature. Spatially resolved CL micrographs for the wavelength range 300 to 850 nm show dark grain-boundary zones and light grain interiors. Corresponding micrographs for the infrared wavelength range 800 to 1800 nm show just the opposite CL contrast. The CL properties of the grain-boundary zone can be correlated to doubly ionized barium vacancies. Therefore, grain-boundary zones which are visible in integral CL images of both wavelength ranges represent the theoretically predicted grain-boundary zone of high barium vacancy concentrations. The width of these grain-boundary zones varies characteristically with sintering time and cooling rate. Additional measurements of the electrical conductivity of the specimens confirmed the theoretically assumed correlation between grain-boundary-zone width and electrical resistance of the samples.     

Soybean seed composition under high day and night growth temperatures

High diurnal temperatures often affect development of soybean [Glycine max (L.) Merr.], but little is known about the relative influence of high day and night temperatures on the chemical composition of the seed. This study was conducted to determine the effects of combinations of high day and night temperatures during flowering and pod set (R1–R5), seed fill and maturation (R5–R8), and continuously during the reproductive period (R1–R8) on soybean seed oil, protein, and fatty acid composition. Day/night temperatures of 30/20, 30/30, 35/20, and 35/30°C were imposed on the soybean cultivar Gnome 85 in growth chambers. The day/night temperature combinations during R1–R5 had little effect on the oil and protein concentration and the fatty acid composition of seed produced. As mean daily temperature increased from 25 (30/20) to 33 (35/30)°C during R5–R8 and 25 (30/20) to 33 (35/30)°C during R1–R8, and oil concentration decreased and protein concentration increased. Increased day temperature during R5–R8 and R1–R8, averaged across the two night temperatures, increased oleic acid and decreased linoleic and linolenic acids. When night temperature was increased at 30°C day temperature during R5–R8 and R1–R8, oleic acid decreased and linoleic acid increased. When night temperature was increased at 35°C day temperature during R1–R8, oleic acid increased, and linoleic and linolenic acids decreased. These results indicate the importance of high day and night temperatures during seed fill and maturation in the oil, protein, and fatty acid composition of soybean seed.