园林空间构成及其文化内涵--以昆山花桥公园为例

以昆山花桥公园规划设计方案为例,阐明园林中如何营造环境优美、尺度适宜的物质空间来构筑深层次的公园精神空间,并强调文化在园林设计中的重要性。该案以“三垣二十八宿”为全园主题思想,三垣对应公园三大主景区,二十八宿环园一周。即以“天文知识”为主线构筑花桥公园的精神空间,展开全园文脉。     

大麦种质耐盐性鉴定及评价

为了鉴定及评价大麦的耐盐性,进行了Na Cl胁迫下不同大麦品种种子萌发及生长试验,结果表明:随着Na Cl胁迫浓度的增加,大麦种子的相对发芽率呈下降趋势,盐害指数随Na Cl胁迫浓度的增加而增大;不同大麦品种间种子萌发存在一定的差异,苏农6472、盐99218、C2118、美97-1338、Numar和海盐大麦表现出较强的耐盐性。通过盐土(土壤含盐量4‰)和脱盐土的对比试验,发现大麦品种在盐土条件下的穗数、穗粒数明显低于脱盐土,而盐土条件下的千粒重高于脱盐土;各品种在盐土下的株高明显低于脱盐土。在盐土条件下,海盐大麦、沪01-2946和苏农6472分别获得4 344、4 311和4 282.5kg·hm-2的籽粒产量,是供试品种中耐盐性最强的品种。本研究不仅为大麦的盐育种提供了理论依据,也为盐渍化地区的麦种植鉴定出了耐盐品种。     

亚热带丘陵几种林地土壤剖面有机碳和轻组有机碳的分布

通过选取亚热带丘陵区3种不同母质发育的林地土壤,分析有机碳及轻组有机碳的剖面分布特征。结果表明:土壤有机碳含量(SOC)、轻组有机碳含量(LFOC)和LFOC/SOC均随剖面深度的加深而降低,分别介于1.49～16.80 g kg-1、0.11～2.58 g kg-1和3.2%～20.2%之间,以表层土壤SOC、LFOC的数量最为丰富、质量最高,且各土壤的剖面分布趋势相似。不同母质发育的剖面土壤发生层有机碳储量介于66.66～95.83 t hm-2,以板岩红壤最高,花岗岩红壤最低;而轻组有机碳储量介于6.09～10.37 t hm-2,以板岩红壤最高,紫色土最低。从储量上看,底土层(B、BC、C层)贮存了主要的有机碳和可观的轻组有机碳。此外,亚热带林地表层土壤LFOC/SOC要高于温带林地表层土壤,这反映出气候、地形和当地土地利用方式对土壤碳质量具有重要影响。     

Isolation of two anti-inflammatory and one pro-inflammatory polyunsaturated fatty acids from the brown seaweed Undaria pinnatifida

Two anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs) of stearidonic acid (SA) and eicosapentaenoic acid (EPA) and one pro-inflammatory omega-6 PUFA of arachidonic acid (AA) were isolated from the edible brown seaweed Undaria pinnatifida. SA was active against mouse ear inflammation induced by phorbol myristate acetate, with IC50 values of 160, 314, and 235 microg per ear for edema, erythema, and blood flow, respectively. EPA was also active against edema, erythema, and blood flow, with IC50 values of 230, 462, and 236 microg per ear, respectively. Although AA at low concentrations showed anti-inflammatory activities when measured 10 h later, AA doses of more than 243 microg per ear induced inflammatory symptoms 1 h later. Mature thalli generally had larger amounts of PUFAs than young thalli. The algal blade contained more omega-3 PUFAs than were found in other parts, while the holdfast contained extremely high amounts of AA. Late-season thalli showed increased amounts of PUFAs, especially AA.     

Inhibition of low-density lipoprotein oxidation and oxidative burst in polymorphonuclear neutrophils by caffeic acid and hispidin derivatives isolated from sword brake fern (Pteris ensiformis Burm.)

Several antioxidant compounds have been previously identified from sword brake fern (Pteris ensiformis Burm.) by DPPH bleaching and Trolox equivalent antioxidant capacity (TEAC) analyses. Among the isolates, 7-O-caffeoylhydroxymaltol 3-O-beta-D-glucopyranoside and hispidin 4-O-beta- D-glucopyranoside [6-(3,4-dihydroxystyryl)-4-O-beta-D-glucopyranoside-2-pyrone] were two new compounds. The aim of this study is to elucidate the possible effect of the aqueous extract of sword brake fern (SBF) and these two compounds in preventing atherosclerosis. The results demonstrated that SBF and these two compounds strongly inhibited Cu2+-mediated low-density lipoprotein (LDL) oxidation measured by thiobarbituric acid-reactive substances assay (TBARS), conjugated diene production, and relative electrophoretic mobility. The commercial antioxidant dl-alpha-tocopherol showed lower antioxidant activity than these two compounds at the same molecular concentration. SBF and these two compounds also suppressed N-formylmethionyl-leucylphenylalanine (fMLP)-stimulated reactive oxygen species (ROS) production in human polymorphonuclear neutrophils (PMN). These findings indicate that sword brake fern may prevent atherosclerosis via inhibition of both LDL oxidation and ROS production.     

Extraction of natural vitamin E from wheat germ by supercritical carbon dioxide

An efficient supercritical fluid extraction (SFE) process with carbon dioxide (SFE-CO(2)) was developed for the extraction of natural vitamin E (V(E)) from wheat germ. Both the pretreatment of extracted wheat germ and extraction conditions were optimized to ensure maximal V(E) yield. The extraction was undertaken at the extracting pressure of 4000-5000 psi, the extracting temperature of 40-45 degrees C, and the carbon dioxide flow rate of 2.0 mL/min for 90 min. An optimized pretreatment of wheat germ was usually necessary with a particle size of 30 mesh and a moisture content of 5.1%. A yield comparison of V(E) and its isomers extracted by supercritical CO(2) with those by conventional solvent extraction suggested that this SFE process was a practical process prospectively superior to conventional solvent extraction to prepare V(E) from wheat germ.     

不同配比改良材料对典型城市绿地土壤物理性质的影响

选择土壤物理性质退化的典型绿地——上海辰山植物园,进行不同配比改良材料的现场试验,结果显示:与对照相比,不同配比改良材料能显著改善土壤物理性质;并以配比3(土︰绿化植物废弃物︰有机肥=8︰3︰0.8和0.5 kg/m3脱硫石膏)改良效果最好,其土壤体积质量最低,土壤含水量、饱和持水量、田间持水量、非毛管孔隙度、毛管孔隙度和有效水含量最高,土壤饱和导水率也达到良好水平。在30、90和180天的试验时间内,同一配比土壤物理性质较稳定;各配比土壤水分特征曲线均较好拟合Gardner模型(R20.9)。砂虽能增加土壤导水率,但对绿地土壤物理性质改良综合效果不及绿化植物废弃物或草炭等有机材料;而脱硫石膏对土壤各物理性质的改良作用随试验时间延长,其作用越来越明显。在所有改良材料中,以有机材料和脱硫石膏混合使用效果最佳。     

石灰性土壤交换性钙和镁测定方法的研究

石灰性土壤交换性盐基组成的测定,通行的方法是采用70%乙醇溶液反复洗盐,再经pH 8.50.1 mol L-1氯化铵-70%乙醇(CH3CH2OH)溶液进行多次交换处理,测定交换液中的K+、Na+、Ca2+、Mg2+浓度。但此方法常常受操作步骤繁琐,以及土壤中碳酸盐的溶解量因多次浸提而增加的困扰,最终导致测定结果偏高。基于上述原因,选择不同浓度、不同pH的NH4OAc和NH4Cl 10种交换剂,对比分析10种交换剂中的碳酸盐溶解度和土壤交换性钙镁含量。结果表明,pH=8.5 1 mol L-1氯化铵-70%乙醇(CH3CH2OH)溶液较适合石灰性土壤交换性盐基的测定。此新方法是先经70%乙醇(CH3CH2OH)溶液洗盐,再用pH8.5 1 mol L-1氯化铵(NH4Cl)-70%乙醇(CH3CH2OH)溶液进行一次性交换处理,然后测定交换液的K+、Na+、Ca2+、Mg2+浓度,简化了操作程序的同时有效抑制了土壤碳酸盐的溶解,降低了测定结果的偏差。     

SRAP标记在五十份新疆人工栽培核桃种质资源的鉴定与应用

以新疆核桃主栽区收集的50份核桃种质资源为试材,采用序列相关扩增多态性(sequence-related amplified polymorphism,SRAP)标记技术分析其遗传多样性,以期为分布于新疆地区的核桃种质资源的保存、鉴定及综合开发利用提供参考依据。结果表明:从100对引物中筛选出16对扩增条带清晰、稳定性好的多态性SRAP引物组合,16对引物组合在50份供试种质中共扩增出178条带,多态性条带135条,多态位点百分率为75.84%。聚类分析及聚类锐度测试显示供试种质可分为10类,热图显示出不同引物对种质的区分情况,多元回归树显示不同引物中的26个扩增条带能够区分50份供试种质,其中M4/E4、M7/E5、M14/E4、M2/E11、M3/E4、M2/E4、M12/E13、M7/E1、M14/E13和M1/E3共10对引物组合是供试种质鉴定中重要的引物组合。同时R语言在统计分析中的应用,为今后核桃植物形态与遗传变异研究提供了新的数据分析方法。     

2020年新疆兵团棉花前期主要病虫害发生情况及中后期防控技术

介绍了2020年新疆生产建设兵团棉花主要病虫害前期发生情况,提出棉花病虫害防治策略及中后期防控技术,为做好兵团棉花铃期防病虫保铃保蕾及棉花丰产丰收提供参考。