Antiproliferative activity of Saponaria vaccaria constituents and related compounds

Total methanolic extracts of Saponaria vaccaria seed derived from several varieties, as well as various purified components obtained through successive chromatographic separations of total extracts were evaluated for their growth inhibitory activity in WiDr (colon), MDA-MB-231 (breast), NCI-417 (lung) and PC-3 (prostate) human cancer cells as well as the non-tumorigenic fibroblast BJ (CRL-2522) cell line using MTT colorimetric assay. Purified bisdesmosidic saponins segetoside H and I were further examined using microscopy and apoptosis assays. Bisdesmosidic saponins exhibited dose-dependent growth inhibitory and selective apoptosis-inducing activity. Growth inhibitory effects were particularly strong in a breast (MDA-MB-231) and a prostate (PC-3) cancer cell line. Total extracts exhibited a different preference being most active against a colon cancer cell line (WiDr). In a comparison of varieties, all of the total seed extracts exhibited similar dose-dependent activities, but with some variation in potency. Monodesmosidic saponins vaccarosides A and B, phenolic vaccarin, and cyclopeptide segetalin A, co-occurring seed substituents, did not exhibit activity. The non-tumorigenic fibroblast cell line BJ (CRL 2522) was growth inhibited but did not undergo apoptosis when treated with bisdesmosidic saponins at low micromolar concentrations. Saponin-rich extracts from Kochia scoparia seed and Chenopodium quinoa were also evaluated alongside Saponaria saponins but did not exhibit activity. Closely related Quillaja saponins exhibited activity but were less potent.     

基于高分2号遥感数据估测中亚热带天然林木本植物物种多样性

[目的]探索高分2号遥感数据与中亚热带天然林木本植物物种Shannon-Wiener多样性指数、Simpson多样性指数和Pielou均匀性指数之间的关系,为森林经营管理和保护策略提供参考。[方法]提取高分2号多光谱数据的原始波段、植被指数、纹理特征和全色波段纹理特征,使用随机森林算法筛选变量并对3种多样性指数进行建模,设置不同纹理提取窗口来寻找最优窗口。[结果]基于随机森林算法的RFE冗余变量去除方法可从众多遥感变量中快速选择对模型精度具有显著贡献的少量变量。多光谱数据3×3窗口纹理特征、全色数据7×7窗口纹理特征和植被指数结合的特征集对3种多样性指数具有较好估测结果,其决定系数（R²）和均方根误差（RMSE）分别为0.47和0.300（Shannon-Wiener多样性指数）、0.53和0.042（Simpson多样性指数）、0.61和0.051（Pielou均匀性指数）。植被指数中类胡萝卜素反射率指数与3种多样性指数具有显著相关关系。[结论]高分2号遥感数据中的植被指数和纹理特征可有效估测研究区森林木本植物物种多样性。类胡萝卜素反射率指数可体现森林中类胡萝卜素相对于叶绿素的含量,在秋冬季节作为反映常绿树种和落叶树种分布的指数,对森林木本植物物种多样性估测具有最大贡献。使用星载遥感数据预测的多样性和均匀性指数分布可有效监测森林木本植物物种多样性变化。     

Effects of biochar and litter on carbon and nitrogen mineralization and soil microbial community structure in a China fir plantation

To investigate the effects of biochar addition(1 or 3%)to the soil of a China fir plantation with or without litter,we conducted a 90-day incubation experiment.We also studied the C and N dynamics and the microbial community structure of the soil.In soil without litter,the application of biochar at a rate of 3%significantly decreased CO2 emissions,while addition of 1%biochar had no effect.Biochar application did not affect the net N mineralization rate but significantly reduced the NH4?concentration after 90 days.In litter-enriched soil,biochar application had no significant effect on total CO2 emissions;however,application of 3%biochar significantly reduced the net N mineralization rate.Biochar application to soil with or without litter immediately reduced the dissolved organic carbon(DOC)concentration independent of the application rate,which was primarily due to sorption of DOC by the biochar.Phospholipid fatty acid analysis demonstrated that both concentrations of added biochar to soil(with or without litter)altered the soil microbial community structure at the end of incubation,although the effect of biochar was not as strong as the effect of time or litter application.The effect of biochar addition alone on microbial community structure was inconsistent over time.Litter added to soil significantly increased fungi and reduced Gram-positive bacteria.In the presence of litter,biochar applied at both 1%and 3%significantly increased(p<0.05)the proportion of actinomycete only at day 90.Our results indicate biochar as a potentially effective measure for C sequestration in the test soil of a China fir plantation,even in the presence of litter.     

杨木浸渍填充改性实验

通过浸渍填充碳酸钠和氯化钙两种不同的无机盐溶液,使浸入木材的钙离子与碳酸根离子结合。在木材微纤丝间隙和管胞的胞腔中生成稳定的固体化合物碳酸钙,从而使杨木中填充了大量的无机物,得到无机复合木材。实验表明当温度为60℃、CaCl2溶液浓度为40%、Na2CO3溶液浓度为25%时,木材增重率最大,可达32.4%;而且处理过的杨木试件的硬度均比未处理高,且硬度平均提高24.36%。     

辽宁省能源消费结构和CO_2排放研究

就能源结构和各部门的能源消费进行研究,推算了辽宁省2000～2005年各种能源消费量及其引起的CO2排放量。辽宁省的主要的能源消费类型是煤炭和石油,在2005年,煤炭和石油的消费量都最多,分别为2 470.16×104t.a-1标准煤和2 932.18×104t.a-1标准煤,也是主要的CO2排放源。以煤炭为原料生产的焦炭的CO2排放量由于技术的提高而减少。从消费部门看,工业部门的能源消费量最多,从2000年的431.55×104t.a-1标准煤增加到2005年的1 096.1×104t.a-1标准煤。交通部门的消费比例从2000年的9%增加到2005年的20%,未来还有增加的趋势。不同部门排放的CO2量也不同,工业部门每年排放的CO2最多,都在2 500×104t.a-1以上,2005年达到了3 020.48×104t.a-1,农林渔牧业部门由于机械化的操作使得CO2排放量增加。     

肋果沙棘幼苗对CO2浓度升高的生理生态响应

通过测定CO₂浓度倍增条件下肋果沙棘幼苗气体交换特征、水分利用效率、叶片性状和生长特性,研究青藏高原特有种肋果沙棘对大气CO₂浓度升高的生理生态响应。结果表明: CO₂浓度倍增可显著提高肋果沙棘幼苗的净光合速率、水分利用效率,促进幼苗营养器官(根、茎、叶)生物量和总生物量的积累,且肋果沙棘趋于向地上部分(尤其是茎)分配更多的干物质。CO₂浓度倍增使肋果沙棘幼苗比叶面积、平均单叶面积、叶片氮含量分别降低27%,33%和41%,碳氮比增加73%,而叶片碳含量无显著影响。CO₂浓度升高条件下肋果沙棘幼苗不仅通过增加光合能力、水分利用效率和生物量累积产生明显的\"施肥效应\",而且通过降低比叶面积、平均单叶面积和叶片氮含量表现出较强的下调适应能力,进而有利于其应对更为复杂的生存环境。     

ClO_2对鲜切莲藕微生物和感官品质的影响研究

以鲜切莲藕为实验对象,研究了不同浓度的ClO2在不同的处理时间下,对鲜切莲藕中微生物及感官品质的影响。实验结果表明,在一定范围内,ClO2的浓度越高,越能有效控制鲜切果蔬中的微生物数量和增长速度,以减少其腐烂率。采用高浓度ClO2和适宜处理时间处理,可较好地保持鲜切莲藕的感官品质。     

口蹄疫OA／58病毒株VP2蛋白结构模拟与B细胞抗原表位的分析

以口蹄疫病毒株OA/58 RNA为模板,反转录并扩增目的cDNA,然后与pMD18-T载体连接并转化JM109菌株,提取的重组质粒用凝胶电泳、PCR和BamH I,Hind III双酶切法鉴定。运用同源模建得到OA/58 VP2蛋白三维空间结构,并结合理化性质、亲水性、可塑性和免疫原性进行分析,找出OA/58 VP2蛋白的B细胞抗原表位。结果表明,OA/58 VP2蛋白存在多个潜在的抗原表位,可能的蛋白质抗原表位区域:1~23,40~63,71~78,82~91,102~106,113~119,131~138,148~154,166~177,189~196,212~218。应用同源模建得到的OA/58 VP2蛋白三维空间结构来预测其B细胞表位,为进一步研究OA/58 VP2蛋白在引起易感宿主体液免疫应答方面提供了一种可视化的技术平台,并且为选择表达其他口蹄疫病毒株的VP2蛋白分子提供有参考价值的信息。     

木材锯切表面粗糙度二维分析与三维分析对比

使用传统的二维轮廓测定方法,测量木材锯切表面粗糙度准确度不高。利用三维表面轮廓成像技术测定木材锯切表面粗糙度,可获得较为准确的检测值和更真实的锯切表面微观形貌。     

新疆药用植物黑桑的抗氧化性

为寻找一种天然的抗氧化材料,以新疆药用植物黑桑的根、枝、叶和果实的乙醇提取物为材料,进行总多酚、总黄酮、抗氧化能力以及螯合Fe²⁺测定。结果显示：果实（桑椹）提取物（EEMF）的总多酚含量（0.943 8 mg·mL^-1）以及总黄酮含量（0.174 7 mg·mL^-1）与叶提取物（EEML）、枝提取物（EEMB）和根提取物（EEMR）相比并不高,但EEMF的抗氧化能力最强,其清除羟基自由基、DPPH自由基能力分别达到96.46%,96.83%,抑制脂质体氧化能力达到71.14%;此外,EEMF螯合Fe²⁺能力也强于其他3种。表明黑桑4个部位都具有良好的抗氧化能力,且果实最佳。