千岛湖姥山马尾松种群结构和分布格局研究

为研究千岛湖马尾松(Pinus massoniana)种群动态变化,在姥山岛上设置面积为5.76 hm2的固定样地,进行群落学调查。根据野外调查的数据,对马尾松种群的结构和分布格局进行分析。结果表明:马尾松种群1、2级个体数极少,仅占样地中马尾松个体数的0.06%和1.01%,幼苗、幼树储备严重不足,5级个体的比例最高,达到28.28%,马尾松种群径级结构为纺锤型;马尾松种群的存活曲线为凸型。这些均表明马尾松种群的年龄结构趋向衰退型。但马尾松种群中树个体很多,在较长的时期内马尾松还不会退出群落。马尾松种群静态生命表也可看出中一些小型径级的死亡率为负值,也说明马尾松种群幼苗严重缺乏,种群呈衰退趋势。马尾松种群各径级和总体的分布格局均呈聚集分布,从小树→中树→大树聚集指数逐渐减小,种群呈扩散趋势。     

黄雀发声核团与部分听觉中枢内P物质的分布和性双态比较

用免疫组织化学方法研究P物质在雌雄黄雀发声控制核团和听觉中枢内的分布,结合计算机图像分析仪检测SP免疫阳性细胞和末梢的灰度值,并作雌雄比较。结果如下：1．在发声学习中枢嗅叶X区有大量的SP阳性神经末梢和一些神经细胞。2．在发声控制核团前脑高级发声中枢(HVc)、古纹状体栎核、发声学习中枢新纹状体巨细胞核和丘脑背内侧核外侧部内有许多的SP免疫阳性细胞。3．在发声控制中枢中脑背内侧核和延髓舌下神经核气管鸣管部、听觉中枢丘脑卵圆核的壳区、中脑背外侧核壳区及中脑丘间核等有密集的SP免疫阳性神经末梢和纤维分布;雄性发声中枢内SP的分布比雌性丰富,两者有显著的差异。结果表明：SP的分布在雌雄发声中枢之间存在显著的性双态;SP广泛分布于黄雀发声控制核团和部分听觉中枢内,提示SP可能在发声控制及听觉中枢内具有重要的生理功能。     

多个地区植物区系丰富性的综合评判

本文介绍了模糊数学中综合评判的原理及二种方法,通过贵州、云南、四川、广西、湖南、湖北、广东、安徽、海南等九省区种子植物区系科、属、种数目的分析,解决了多个地区植物区东丰富性综合比较及其评价这一问题。结果与实际情况基本一致,尤其方法Ⅱ比方法Ⅰ的效果更佳。     

SRNAome and degradome sequencing analysis reveals specific regulation of sRNA in response to chilling injury in tomato fruit

Plant genomes encode diverse small RNA classes that function in distinct gene‐silencing pathways. To elucidate the intricate regulation of microRNAs (miRNAs) and endogenous small‐interfering RNAs (siRNAs) in response to chilling injury in tomato fruit, the deep sequencing and bioinformatic methods were combined to decipher the small RNAs landscape in the control and chilling‐injured groups. Except for the known miRNAs and ta‐siRNAs, 85 novel miRNAs and 5 ta‐siRNAs members belonging to 3 TAS families (TAS5, TAS9 and TAS10) were identified, 34 putative phased small RNAs and 740 cis/trans‐natural antisense small‐interfering RNAs (nat‐siRNAs) were also found in our results which enriched the tomato small RNAs repository. A large number of genes targeted by those miRNAs and siRNAs were predicted to be involved in the chilling injury responsive process and five of them were verified via degradome sequencing. Based on the above results, a regulatory model that comprehensively reveals the relationships between the small RNAs and their targets was set up. This work provides a foundation for further study of the regulation of miRNAs and siRNAs in the plant in response to chilling injury.     

川西高原季节性雪被覆盖对窄叶鲜卑花凋落物分解和养分动态的影响

2010年1-5月在川西高原采用人工雪厚度梯度试验(0、30和100 cm),应用网袋分解法对窄叶鲜卑花叶片凋落物进行分解试验,测定了凋落物的分解速率及其养分动态.结果表明:在无雪被覆盖的样地上分解5个月后的凋落物质量损失率为29.9％,而中雪和深雪样地的凋落物质量损失率分别为33.8％和35.2％.分解过程中,凋落物氮存在一定的富集现象,磷处于波动的富集状态,碳质量分数和碳氮比均呈现前期急剧下降后期逐渐上升的趋势.雪被覆盖显著增加了凋落物的质量损失率和氮含量,而对碳和磷含量无显著影响.在川西高原地区,30 cm以上的持续雪被覆盖能够改变凋落物的分解过程,从而可能对土壤营养物质转化和植物群落构建产生实质性的影响.     

Epac‐2 ameliorates spontaneous colitis in Il‐10 −/− mice by protecting the intestinal barrier and suppressing NF‐κB/MAPK signalling

Intestinal barrier dysfunction and intestinal inflammation interact in the progression of Crohn''s disease (CD). A recent study indicated that Epac‐2 protected the intestinal barrier and had anti‐inflammatory effects. The present study examined the function of Epac‐2 in CD‐like colitis. Interleukin‐10 gene knockout (Il‐10 ^−/−) mice exhibit significant spontaneous enteritis and were used as the CD model. These mice were treated with Epac‐2 agonists (Me‐cAMP) or Epac‐2 antagonists (HJC‐0350) or were fed normally (control), and colitis and intestinal barrier structure and function were compared. A Caco‐2 and RAW 264.7 cell co‐culture system were used to analyse the effects of Epac‐2 on the cross‐talk between intestinal epithelial cells and inflammatory cells. Epac‐2 activation significantly ameliorated colitis in mice, which was indicated by reductions in the colitis inflammation score, the expression of inflammatory factors and intestinal permeability. Epac‐2 activation also decreased Caco‐2 cell permeability in an LPS‐induced cell co‐culture system. Epac‐2 activation significantly suppressed nuclear factor (NF)‐κB/mitogen‐activated protein kinase (MAPK) signalling in vivo and in vitro. Epac‐2 may be a therapeutic target for CD based on its anti‐inflammatory functions and protective effects on the intestinal barrier.     

Estimation of a novel method to produce bio-oil from sewage sludge by microwave pyrolysis with the consideration of efficiency and safety

This paper presented a feasible method to produce bio-oil from sewage sludge by microwave pyrolysis. The results showed that oils derived under 400 W obtained an attractive yield (49.8 wt.%) with favorable characteristics such as high calorific value (35.0 MJ/kg), low density (929 kg/m3) and preferable chemical composition (29.5 wt.% of monoaromatics). A model to study the relationship between microwave power and mass balance of product fractions was developed, and the results indicated that the power range of the highest transforming efficiency for organics in sludge into oils was 400-600 W, the subsequent increase of power to the range of 600-800 W favored gases formation at the expense of oils, and increase of power to above 800 W led to the conversion of solids into gases, while oils remained unchanged. The analysis of sulfur and nitrogen compounds in oils showed that bio-oil should be extracted before being used as fuel.     

X射线辐射对仔鼠消化酶活性及胃中Bax和Ghrelin表达的影响

为了探讨X射线辐射对仔鼠胃蛋白酶活性、十二指肠脂肪酶活性及胃中Bax蛋白和Ghrelin表达的影响,对170只仔鼠用不同辐射剂量（0,4,12,20,28 Gy）X射线进行全身辐射,分别在辐射后1,5,10,20 d用比色法检测仔鼠胃蛋白酶活性和十二指肠中脂肪酶活性的变化,用免疫组织化学方法检测胃中Bax蛋白和Ghrelin的表达和分布,并用Image-proplus 5.0专业图像分析软件检测Bax蛋白和Ghrelin在胃中的表达强度。结果表明,X射线辐射影响发育期仔鼠胃蛋白酶和十二指肠脂肪酶的活性以及胃中Bax蛋白和Ghrelin的表达。仔鼠胃蛋白酶活性除在辐射后1 d时高于对照组外,其它辐射后各期均低于对照组,仔鼠十二指肠中脂肪酶活性在辐射后均低于对照组;Bax蛋白主要在仔鼠胃黏膜上皮细胞中表达,其表达水平随辐射剂量的增大而增强;Ghrelin主要在胃内分泌细胞中表达,辐射后其表达水平降低。X射线辐射影响仔鼠消化酶活性,这可能与胃中Bax蛋白和Ghrelin的表达变化有关。