Radical scavenging activity of protein from tentacles of jellyfish Rhopilema esculentum

In this study, radical scavenging activity of protein from tentacles of jellyfish Rhopilema esculentum (R. esculentum) was assayed including superoxide anion radical and hydroxyl radical scavenging. The protein samples showed strong scavenging activity on superoxide anion radical and values EC50 of full protein (FP), first fraction (IFF), second fraction (SF), and 30% (NH4)(2)SO4 precipitate (Fr-1) were 2.65, 7.28, 1.10, and 22.51 mu g/mL, respectively, while values EC50 of BHA, BHT, and alpha-tocopherol were 31, 6 1, and 88 pg/mL, respectively. Also, the protein samples had strong scavenging effect on hydroxyl radical and the values EC50 of FP, FF, SF, Fr-1, and Fr-2 were 48.91, 27.72, 1.82, 16.36, and 160.93 mu g/mL, but values EC50 of Vc and mannitol were 1907 and 4536 mu g/mL, respectively. Of the five protein samples, SF had the strongest radical scavenging activity and may have a use as a possible supplement in the food and pharmaceutical industries. The radical scavenging activity was stable at high temperature so that R. esculentum may be used as a kind of natural functional food. (c) 2005 Elsevier Ltd. All rights reserved.

A new three-phase culture method for Manila clam, Ruditapes philippinarum, farming in northern China

Studies on reproduction, hatchery management, and culture of Manila clams Ruditapes philippinarum were carried out in an attempt to optimize their culture conditions and techniques. Results from these studies led to the development of a three-phase culture method for Manila clam farming in northern China. The key components of the new method were: 1) early spawning and over-wintering indoors (greenhouse); 2) optimized larval culture conditions and techniques; 3) juvenile rearing in shallow, fertilized nursery ponds; 4) optimized stocking size and density and substrate for mudflat grow out. Broodstock were maturated indoors for a month from early April to early May. Primarily because of higher water temperatures in the greenhouse the clams spawned more than one month earlier than in the natural environment. From May to July, juveniles were reared for 1-2 months indoors to a size of 2.0-3.0 mm in shell length before being moved to outdoor, pre-disinfected, nursery ponds. Juveniles were then reared in the nursery ponds for one month to about 1.0 cm before being transferred to the mudflat for grow out. Juvenile clams in nursery ponds grew considerably faster than in the natural environment probably because of higher temperatures and more abundant natural food. During grow out, the clams were reared for 4-7 months until they reached a market size (3.0-3.3 cm). Juveniles produced after August were over-wintered in the greenhouse in which the water temperature was about 3 degrees C higher than that of the outdoor environment. Juveniles grew at an average rate of > 20 mu m day(-1), while in the natural environment no growth was observed during winter because of low temperatures. Juveniles in the greenhouse grew to 2-3 mm by the following March before being moved into outdoor nursery ponds. The three-phase culture method not only shortened the production period from spawn to market size from 24-36 months to about 10-14 months, but also prolonged the spawning season from 2 to 7 months, resulting in increased production of seed and market-size clams. Compared with the traditional method, the new method could increase the yield of market-size clams by 10-11 times, and increase the profit per ha mudflat by as much as 124 times and the profit per kg market-size clams produced by 13 times. (c) 2006 Elsevier B.V. All rights reserved.

小麦高分子量谷蛋白亚基表达量与面团流变学特性的关系

应用SDS-PAGE技术依据HMW-GS组成型从来自全国10个省（区）、市的小麦品种（系）中筛选出20个,分为5组。准确提取各品种的高分子量谷蛋白,并将SDS-PAGE谱带用凝胶成像系统（Bio-imagingSystem）和Labworks5.0进行亚基定量分析,并进行了面团流变学特性测定,所得数据用SPSS14.0进行统计分析。结果表明,HMW-GS总表达量在各品种间的差异达到极显著水平,所有品种中各亚基的平均表达量10〉7〉5〉1〉8〉12〉2〉9;HMW-GS总表达量及HMW-GS占籽粒蛋白质含量的比例与面团形成时间、稳定时间和粉质评价值之间呈显著正相关;分组比较单个亚基对品质性状的影响表明,亚基1优于null,5＋10优于2＋12,7＋8和7＋9相当。研究发现不具有优质亚基组成、但HMW-GS表达量高的品种品质也较好,因此在小麦品质育种中,在注重HMW-GS组成筛选的同时,要注重保留HMW-GS表达量高的材料。

高原鼠兔家群结构的季节变异

采用标志重捕法测定高原鼠兔家群年龄结构和性比,探讨其家群结构的季节变异及原因.结果显示,繁殖早期,家群由越冬成体和第1胎幼体构成;繁殖后期,家群主要由第1胎幼体构成.高原鼠兔家群年龄结构依季节存在显著的差异.5月,成体和雌性第1胎幼体个体数显著多于其他月份;5月和6月雄性第1胎幼体个体数显著多于7月和8月;6月第2胎幼体个体数显著多于7月和8月;7月雄性第2胎幼体个体数显著多于8月.7月和8月,第1胎幼体个体数显著多于第2胎幼体.高原鼠兔家群内5月成体性比显著高于7月和8月.结果表明,高原鼠兔在冬季漫长、食物匮乏以及繁殖季节极短等条件下,调整家群结构,提高繁殖成功率,使其种群在严酷的高寒环境中得以延续.

氢氧化锂存在下（焦）脱镁叶绿酸-a甲酯的空气重排反应

在氢氧化锂存在下，脱镁叶绿酸-a甲酯（1a）发生空气氧化和重排反应，经盐酸酸化和重氮甲烷甲基化，得到由紫红素-7三甲酯（2）、紫红素-18甲酯（3）、卟吩-P6三甲酯（4）、地质卟啉衍生物（5）和3-环氧乙基-3-去乙烯基紫红素-18甲酯（6）所组成的混合物．用相同的方法处理焦脱镁叶绿酸-a甲酯（1b），则分离出13^2-氧代焦脱镁叶绿酸-a甲酯（7）、15-甲酰基紫红素-5二甲酯（8）、紫红素-18甲酯（3）和3-环氧乙基-3-去乙烯基紫红素-18甲酯（6）-所得新叶绿素衍生物5，6和8的化学结构均经UV，IR，^1H NMR及元素分析得以证实，并对相应的反应提出可能的反应机理．

高寒湿地太阳辐射和地表反射率变化的统计学特征

依据祁连山海北高寒湿地植物生长期观测的太阳总辐射(E_g)和反射辐射(E_r)资料, 分析了高寒湿地Eg和地表反射率(A)的日及季节变化特征. 结果表明:祁连山海北高寒湿地, 有较强的Eg, 但A较低. 年内1～12月E_g的平均日总量达17.3 MJ•m~(-2), 其中植物生长期的5～9月平均日总量为20.0MJ•m~(-2), 表现出4～7月高, 冷季低的变化特征. A的日、季节变化均表现 "U"型变化过程. 2004年1～12月A的年平均值为0.32, 植物生长季的5～9月平均值为0.18, 植物非生长季的10月～翌年4月平均值为0.43. 其中1月最高(0.70), 7月最低(0.16).

甘肃胡麻地方种质资源品质特性研究

对甘肃省116份胡麻地方品种的重要品质指标--粗脂肪、硬脂酸、棕榈酸、油酸、亚油酸、亚麻酸含量和碘值进行测定,并根据这些品质指标对供试品种进行聚类分析.结果显示:(1)供试品种粗脂肪含量平均值为37.48%,变异系数3.8%;硬脂酸、油酸含量平均值分别为5.32%和29.05%,变异系数分别为19.5%和11.6%;棕榈酸、亚麻酸、亚油酸含量平均值分别为5.9%、48.76%、10.95%,变异系数分别为8.4%、8%、8%;平均碘价175.60,变异系数2.76%;(2)聚类分析结果显示,116个品种聚为7大类,其中:b亚组群硬脂酸和油酸含量最高,而亚麻酸含量最低;d亚组群品种亚麻酸含量最高;e亚组群粗脂肪含量和碘价最高,油酸含量最低;f亚组群硬脂酸含量最低;g亚组群棕榈酸含量最高,碘价最低.

藏药大果大戟中的巨大戟烷型二萜酯类成分

目的研究藏药大果大戟Euphorbia wallichii丙酮提取物中的化学成分。方法用溶剂提取，常规硅胶柱色谱分离和葡聚糖凝胶Sephadex LH-20纯化，采用化学方法和现代波谱分析技术（包括IR，HRESIMS，HRSIMS，1D和2DNMR等）鉴定其化学结构。结果从青海产大果大戟根的丙酮提取物中分离得到6个化合物，分别鉴定为：羊毛甾醇（lanosterol，Ⅰ）、巨大戟二萜-20-肉豆蔻酸酯（ingenol-20-myristinate，Ⅱ）、巨大戟二萜-3-肉豆蔻酸酯（ingenol-3-myristinate，Ⅲ）、没食子酸（gallicacid，Ⅳ）、1-O-a-L-阿拉伯糖-（1→6）-β-D-葡萄糖苷-3，7-二甲基-2-烯-7-羟基-辛醇（1-O-a-L-arabinofuranosyl-（1→6）-β-D-glucopyranosyl-3，7-dimethyl-oct-2-en-7-ol，Ⅴ）、1-O-没食子酰葡萄糖苷（1-O-galloyl-β-D-glucose，Ⅵ）。结论巨大戟烷型二萜酯类化合物Ⅱ和Ⅲ为新化合物，其他化合物均为首次从该植物中分离得到，单萜二糖苷类化合物Ⅴ系首次在该属中发现。

红花岩黄芪化学成分研究

目的:对红花岩黄芪化学成分进行研究。方法:用溶剂法、色谱法提取、分离红花岩黄芪化学成分,用波谱法鉴定其结构。结果:从红花岩黄芪中分离得到7 个化合物,碳三十醇(1) ,二十四碳酸( 2) ,5 ,7-二羟基-4′-甲氧基-6 ,8-二异戊烯基异黄酮(3) ,对香豆酸二十二酯( 4) ,豆甾醇( 5) , 5 ,7-二羟基-4 ,-甲氧基- 6-异戊烯基异黄酮( 6) ,咖啡酸二十四酯( 7) 。结论:化合物3 和4 为新天然产物,其它化合物均为首次从该植物中获得。

Methane emissions by alpine plant communities in the Qinghai-Tibet Plateau

For the first time to our knowledge, we report here methane emissions by plant communities in alpine ecosystems in the Qinghai-Tibet Plateau. This has been achieved through long-term field observations from June 2003 to July 2006 using a closed chamber technique. Strong methane emission at the rate of 26.2 +/- 1.2 and 7.8 +/- 1.1 mu g CH4 m(-2) h(-1) was observed for a grass community in a Kobresia humilis meadow and a Potentilla fruticosa meadow, respectively. A shrub community in the Potentilla meadow consumed atmospheric methane at the rate of 5.8 +/- 1.3 mu g CH4 m(-2) h(-1) on a regional basis; plants from alpine meadows contribute at least 0.13 Tg CH4 yr(-1) in the Tibetan Plateau. This finding has important implications with regard to the regional methane budget and species-level difference should be considered when assessing methane emissions by plants.

Dynamic and complex microclimate responses to warming and grazing manipulations

Synthesis efforts that identify patterns of ecosystem response to a suite of warming manipulations can make important contributions to climate change science. However, cross-study comparisons are impeded by the paucity of detailed analyses of how passive warming and other manipulations affect microclimate. Here we document the independent and combined effects of a common passive warming manipulation, open-top chambers (OTCs), and a simulated widespread land use, clipping, on microclimate on the Tibetan Plateau. OTCs consistently elevated growing season averaged mean daily air temperature by 1.0-2.0 degrees C, maximum daily air temperature by 2.1-7.3 degrees C and the diurnal air temperature range by 1.9-6.5 degrees C, with mixed effects on minimum daily air temperature, and mean daily soil temperature and moisture. These OTC effects on microclimate differ from reported effects of a common active warming method, infrared heating, which has more consistent effects on soil than on air temperature. There were significant interannual and intragrowing season differences in OTC effects on microclimate. For example, while OTCs had mixed effects on growing season averaged soil temperatures, OTCs consistently elevated soil temperature by approximately 1.0 degrees C early in the growing season. Nonadditive interactions between OTCs and clipping were also present: OTCs in clipped plots generally elevated air and soil temperatures more than OTCs in nonclipped plots. Moreover, site factors dynamically interacted with microclimate and with the efficacy of the OTC manipulations.These findings highlight the need to understand differential microclimate effects between warming methods, within warming method across ecosystem sites, within warming method crossed with other treatments, and within sites over various timescales. Methods, sites and scales are potential explanatory variables and covariables in climate warming experiments. Consideration of this variability among and between experimental warming studies will lead to greater understanding and better prediction of ecosystem response to anthropogenic climate warming.

白垩纪超静磁带地球磁场古强度测定

The long-term variations in the strength of the geomagnetic field provide important constraints on the chemical-physical processes of the Earth’s interior. Especially, the intensity of the geomagnetic field during the Cretaceous normal superchron (CNS) is crucial to understand the geodynamo. But a paucity of paleointensity further limits to obtain essential knowledge interior process in the deep earth. In order to improve the experimental efficiency, this study tried to apply two new rock magnetic methods (FORC diagram and low-temperature demagnetization technique) to determine the paleointensity. First, some problems in the theory and technique in paleointensity experiments were introduced. A combined palaeomagnetic and geochronologic study was further conducted on a basaltic lava sequence at Jianchang in Liaoning Province, northeastern China. Radiometric 40Ar/39Ar dating indicates that the volcanism occurred at about 119 Ma within the marine anomaly C34n in Cretaceous normal superchron (CNS). Rock magnetic investigations show that pseudo-single domain (PSD) titanium-poor titanomagnetite is dominant in the studied lava flows. Both stepwise thermal and alternating field demagnetizations isolate the well-defined normal characteristic remanent magnetization (ChRM) in three independent lava flows with a mean direction of D/I = 6.0/51.9 degree(a95 = 12.3degree). Palaeointensity was determined using the modified Thellier method with systematic partial thermoremanent magnetization (pTRM) checks on total 72 samples, but only 10 samples exhibit ideal linear behavior on the Arai-plot in the temperature interval of 300-560 C and yield an average paleointensity of (25.8+/-1.4)uT. In addition, slopes of the line defined by the initial and the final points on the Arai-plot for the other 18 samples with characteristic PSD features give an average paleointensity estimation value of (24.8+/-1.9)uT. The consistency of these two approaches confidently demonstrates the fidelity of our results. The overall mean field strength determined using both approaches are thus estimated to be (25.2+/-0.7 )uT. This value corresponds to the virtual dipole magnetic moments (VDM) of (4.5+/-0.1)E22 Am^2, which is about half of the value of present field. This finding suggests that palaeointensity just at the onset of the CNS is characterized by a weak magnetic field.

宣龙式赤铁矿含矿岩系的成矿过程研究

Xuanlong-type Hematite Deposits, distributed in Xuanhua and Longguang area in Hebei province and hosted in the Changchengian Chuanlinggou Formation of Mesoproterozoic, is an oldest depositional iron deposit characterized by oolitic and stromatolitic hematite and siderite. This thesis made an systematic study of its sedimentary, sedimentology, geochemistry, mineralogy and sequence stratigraphy. Based on above, the mechanism and background of biomineralization are discussed. There are four types of hematite ores including stromatolite, algal oolite, algal pisolite and oncolite. Based on detailed study on ore texture, the authors think both algal oolite and algal pisolite ores are organic texture ores, and related to the role of microorganisms. The process of blue-green algae and bacteria in the Xuanlong basin absorbing, adsorbing and sticking iron to build up stromatolite is the formation process of Xuanlong-type hematite deposit. Researches on ore-bearing series and ore geochemistry show that the enrichment of elements is closely related to the microorganism activities. Fe_2O_3 is enriched in dark laminations of stromatolite with much organic matter and SiO_2 in light laminations with detrital matters. The trace elements, especially biogenic elements, including V, P, Mo are enriched in ores but relatively low in country rocks. The paper also demonstrates on the sequence stratigraphy of hematite deposits and five sequences and twelve systems are divided. The characteristics of sequence stratigraphy show that the deposit-forming location has obviously selectivity and always exists under a transgressive setting. The oxygen isotope in hematite is about -2.2～5.7‰, which is similar to that of Hamlys iron formation of Australia but more negative than that of volcanic or hydrothermal iron deposits characterized by high positive values. The calculation by the result of oxygen isotope analysis shows that the temperature of ancient sea water was 48.53℃. The negative value of carbon isotope from siderite indicates its biogenic carbon source. Meanwhile, the occurrence of seismite in the ore-beds, which indicates the formation of hematite deposits is associated with frequent shock caused by structural movement such as distal volcano or ocean-bottom earthquake etc, show the occurrence of hematite deposits is eventual, not gradual. In shorts, Xuanlong-type hematite deposits were the result of interaction among geological setting of semi-isolated Xuanglong basin, favorable hot and humid climate condition, abundant iron source, microorganism such as algae and bateria as well as the fluctuation of the sea level.

太湖北部夏季浮游藻类多样性与水质评价

于2004年7月对太湖北部浮游藻类的种群组成进行了调查，分析了藻类利属组成的空间分布，利用多种多样性评价指数对水体的污染情况进行了评价，初步探讨了太湖藻类种群组成的变化特征。太湖北部浮游藻类的密度较大，介于2．54×10^7～8．53×10^8个·L^-1，主要由蓝藻、绿藻、硅藻、甲藻、裸藻和隐藻等组成，以微囊藻为优势种。自湖岸向湖心，单位体积内藻类的个数及生物量逐渐递减，种属逐渐增加。其中含较多指示污染及富营养化程度的藻类种属，各种评价指数显示水体的污染程度较为严重，属中营养一富营养化范畴.

中旬红山矽卡岩铜矿稳定同位素特征及其对成矿过程的指示

红山铜矿床位于三江地区义敦岛弧南端的中甸弧，是在晚三叠世甘孜-理塘洋盆向西俯冲过程中形成的一个中型规模的矽卡岩矿床。通常，矽卡岩体就是铜矿体或铜矿化体，主要呈似层状、层状、脉状及透镜体状产于大理岩与角岩接触带或局部在角岩中，未见其与侵入岩直接接触。通过对不同成矿阶段所形成的石榴石、磁铁矿、磁黄铁矿、黄铁矿、黄铜矿、方解石等典型矿物以及大理岩的稳定同位素特征研究，发现矽卡岩的最主要组成矿物石榴石的δ^18OSMOW范围为6．2—8．3‰，反映了矽卡岩可能直接继承隐伏斑岩体的氧同位素组成。根据磁铁矿的氧同位素组成（5．5—7．1‰）所计算的磁铁矿化阶段成矿流体的δ^18OSMOW为13．1—14．7‰（400℃）或12．5—14．1％。（500℃），暗示有富集δ^18O的CO2溶入到成矿流体中。硫化物的δ^34SCDT范围4．45—6．20‰，说明矿床具有高度均一的硫源，并且在硫化物的结晶沉淀过程中，流体中硫同位素分馏很弱。由此推测主成矿期成矿流体的δ^34S∑S为5．6±0．6‰。矿床中的大理岩的δ^13CPDB为2．0—2．2‰，δ^18OSMOW为24．0—24．8‰，说明大理岩是由海相碳酸盐岩经重结晶作用而成。成矿晚期阶段形成的方解石脉的δ^13CPDB范围是-2．4—1．7‰，δ^18OSMOW范围是16．3—22．4‰，表明其C和O主要来源于大理岩。总之，我们推测红山矽卡岩很可能主要是由中酸性岩浆浅成侵位时局部同化碳酸盐围岩所形成的一种富含钙质成分的次生岩浆就位于碎屑岩与碳酸盐岩之间的构造薄弱带冷凝固结而成，矽卡岩型矿化与深部斑岩型矿化具有共同的成矿物质和成矿流体来源。