Flower formation induced by kinetin and vitamin E treatment in long-day plant (Arabidopsis thaliana) grown in short day

The Science of Nature -     

短期OTC 处理对鹅绒委陵菜健康影响的研究初报

利用开顶箱（Open Top Chambers, OTC）模拟增温的方法,研究了短期变暖对鹅绒委陵 菜健康的影响。结果表明,短期变暖后降低了鹅绒委陵菜的萌蘖株死亡、增加了单位长度匍匐茎 的萌蘖株数目和其死亡率,同时叶片数目、高度和健康率比对照增加,匍匐茎长度和匍匐茎上萌 蘖株数目比对照减少,同时所有表征指标中只有萌蘖死亡率和叶片高度比对照有显著变化 （p ＜ 0.05）。     

Ultraviolet irradiation induced oxidative stress and response of antioxidant system in an intertidal macroalgae Corallina officinalis L.

The response of the antioxidant defense system of an intertidal macroalgae Corallina officinalis L. to different dosages of UV-B irradiation was investigated. Results showed that superoxide dimutase (SOD) and peroxidase (POX) increased and then maintained at a relatively stable level when subjected to UV-B irradiation. Catalase (CAT) activity under medium dosage of UV-B irradiation (Muv) and high dosage of UV-B irradiation (Huv) treatments were significantly decreased. Ascorbate peroxidase (APX) activity first remained unaltered and then increased in Huv treatment. In addition, the assay on isozymes was carried out using non-denaturing polyacrylamide gel electrophoresis (PAGE). The activities of some SOD isoforms were altered by UV-B. Two new bands (POX V and POX Ⅶ) appeared upon exposure to all three UV-B dosages. CAT Ⅲ activity was increased by low dosage of UV-B irradiation (Luv),whereas CAT Ⅲ and CAT Ⅳ disappeared when the alga was exposed to Muv and Huv. Two bands of APX (APX Ⅵ and APX Ⅶ)were increased and a new band (APX X) was observed under Huv exposure. H2O2 and thiobarbituric acid reacting substance (TBARS)increased under Muv and Huv treatments. Overall, UV-B protection mechanisms are partly inducible and to a certain extent sufficient to prevent the accumulation of damage in C officinalis.     

叶酸、L-苯丙氨酸、维生素E废水治理方案研究

根据叶酸、L-苯丙氨酸、维生素E废水水质酸度高、色度深、盐度高、有机物含量高、可生化降解性差的特点,选择了"化学中和十兼氧/好氧PACT生化处理工艺".运行结果表明,经该工艺处理后,废水中的COD、BOD5、色度、PH等指标均能达标排放.     

武汉市霾天气过程冷锋和降水对PM2.5输送和清除效应分析

基于2013—2016年93次冷锋影响过程,研究了冷锋和降水对武汉市PM_(2.5)浓度增加和降低的影响机制,并对浓度下降幅度开展了定量分析.结果表明:受冷锋影响PM_(2.5)浓度变化表现为"两类五型",其中,PM_(2.5)浓度下降占比为62%,平均下降幅度为41μg·m~(-3),主要发生在中等强度冷锋过程中,下降幅度最大时24 h变温、24 h变压和极大风速的区间分别为-4～-2℃、8～12 hPa和8 m·s~(-1);而PM_(2.5)浓度上升主要出现在弱冷锋影响下,上升幅度最大的相应区间分别为-2～0℃、6 hPa和4 m·s~(-1).直接下降型风速最大,直接上升型冷锋强度偏弱,先升后降型PM_(2.5)浓度平均值最高.71%的冷锋过程伴有降水.对于重污染过程,污染持续时间最长的天气型为低压倒槽,PM_(2.5)浓度值最大的天气型为均压场.同时,清除方式中冷空气和降水共同作用占44.4%,单纯冷空气影响占37.0%,仅冷空气作用时的清除速度最快,下降速度为71.1μg·m~(-3)·d~(-1),但结束时的浓度最高;配合降水时清除效果明显,结束浓度一般在46μg·m~(-3)左右,但清除速率较小.     

不同浓度铵态氮对苦草的生理影响

研究了苦草在不同浓度(0.02,0.05,0.10,0.30,0.60,1.00,3.00mg/L)铵态氮中暴露14d后,其生物量的变化、叶片游离氨基酸态氮、叶绿素、可溶性蛋白含量以及O2-×信号强度、抗氧化酶活性和丙二醛(MDA)含量的响应.结果表明,各浓度组苦草的生物量无显著变化,但是各生理指标变化显著.当铵态氮浓度为0.30mg/L时,苦草叶片中游离氨基酸态氮的含量即开始显著升高.当铵态氮浓度达到0.60mg/L时,超氧化物歧化酶(SOD)活性显著升高,表明苦草诱导产生氧化应激但未受到氧化损伤.当铵态氮浓度高于1.00mg/L时,SOD和过氧化物酶(POD)活性显著升高,O2-×信号强度显著增强,叶绿素、可溶性蛋白含量显著降低.当铵态氮浓度为0.02mg/L时,O2-×信号强度显著增强.综上,铵态氮浓度低于0.60mg/L苦草生长良好,浓度31.00mg/L苦草光合能力受到抑制、代谢受到干扰.苦草对铵态氮最敏感的生理生化指标是叶片中游离氨基酸态氮含量.铵态氮作为沉水植物的一种营养物质,当其含量较低时,植物由于营养缺乏诱导产生自由基.     

量子点-Cu2+对L02细胞的联合毒性及NAC的防护作用

以人胚肝细胞(L02)为研究对象,通过研究量子点及Cu2+ (低毒浓度)联合对细胞存活率的影响以及细胞形态的变化确认细胞的毒性,结合抗氧化剂NAC的防护效果探讨复合毒性的氧化损伤机理.结果表明,无论单独Cu2+还是量子点-Cu2+处理组,L02细胞的增殖能力均受到抑制,量子点-Cu2+处理组表现出更加显著的抑制效果,相对与单独Cu2+处理组细胞存活率最大下降300%.经过NAC预处理的细胞在形态和存活率上都显著恢复.说明了安全浓度范围的量子点的与Cu2+共存提高了细胞毒性风险,NAC能够防护量子点与Cu2+单独或联合引起的氧化损伤.     

国外体育教学对我国高校体育改革的启示

借鉴德国和俄罗斯的体育教育的思想观念,对高校体育对学生的作用、社会功能、心理功能等进行了分析,从而对高校体育的性质和功能进行了重新定位和理解。提出体育教改应从转变培养观念入手,理解健康新概念,全面重视学生身心成长,贯穿“个体化、专项化、社会化”的思想。     

Effects of some eucalypts on yields of Vigna unguiculata L. Walp., Zea mays L. and Sorghum bicolor L.

Vigna unguiculata (beans), Zea mays (maize) and Sorghum bicolor (sorghum) were grown with and without fertiliser in a savanna grassland (control) and under the effects of decomposing parts of eucalyptus in an old eucalyptus plantation with a well-lit floor (treatment).Morphological characters of the beans, compared between the two sites, showed that leaf dry-matter production, expressed as specific leaf area (SLA), did not differ between plants in the two sites (fertilised and unfertilised). Although the organic-matter content and water-holding capacity of the plantation soil were significantly higher than those of the control plants. beans, grain yield ha⁻¹, shoot height, number of leaves and fruits were higher in the control plants. However, when beans were fertilised, shoot height did not differ between sites, but the other measured morphological characters and grain yield were significantly improved in both sites, although these characters still remained higher in the control. In maize and sorghum, grain yield ha⁻¹ did not vary significantly in the two sites (fertilised or unfertilised). These findings suggest that beans can be incompatible with eucalypts, while maize and sorghum may be compatible with eucalypts for agrosilvicultural practices, and that fertilisation can offset, to an extent, the depressive effects of eucalypts on crops.     

露天矿开采对区域生态完整性的影响研究—田家沟矿区钛磁铁矿为例

在介绍生态完整性的概念及其度量方法的基础上,以湖北省丹江口市田家沟矿区钛磁铁矿为例,从自然体系生产力、景观生态体系质量与生态系统脆弱性3个方面,阐述了露天矿开采对区域生态完整性产生的影响。结果表明：区域生物生产力的变化仅局限于项目区内;作为模地的林地优势度值从84．64％降低到80．15％,下降的幅度较小,恢复稳定性和阻抗稳定性变化也不大;各植被群落的脆弱性均属于轻微脆弱,在受到人为干扰时,森林生态系统具有稳定性和可恢复性。因此工程建设对区域生态完整性的影响在可承受的范围之内。