马铁菊头蝠不同状态下回声定位声波分析

在自建网室(9 m×4 m×4 m)内驯养马铁菊头蝠(Rhinolophus ferrumequinum),利用超声波探测仪录制蝙蝠不同状态下回声定位声波,声波录制与红外摄像保持同步。结果表明,马铁菊头蝠回声定位声波为调频(FM)/恒频(CF)/调频(FM)型;在蝙蝠接近猎物过程中,声脉冲持续时间和间隔时间显著变短,下调FM(即tFM)组分变得愈为显著,捕捉猎物瞬间,产生捕食蜂鸣;飞行与悬挂状态相比,声脉冲重复率、主频率、声脉冲时间、声脉冲间隔和能率环的差异均达到显著水平。

施肥对黑土土壤微生物生物量碳的作用研究

长期施肥对黑土耕地表层土壤微生物生物量碳 (MBC)的作用研究结果表明 ,NPK化肥配施可保持休闲地土壤微生物生物量碳含量至 1.6g/kg水平 ;高量有机肥与无机肥配施可比休闲地土壤微生物生物量碳含量提高 1.96～ 2 .75倍 ;长期耕种与施肥对土壤微生物生物量碳含量产生衰减影响 ;各处理土壤微生物生物量碳含量增加依次为M2 +NPK(+14 1.2 5 % ,1990年始处理 ) >M4+NPK(+12 6 .88% ) >M2 +NPK(+10 1.2 5 % ,1980年始处理 ) >M4+CK(+80 .6 3% ) >(M1+NPK)× 1.5 (+13.13% ) >NPK(+8.12 % ) ,各处理土壤微生物生物量碳含量减少依次为M0+NPK(- 3.75 % ) >M1+NPK(- 17.5 0 % ) >M2 +CK(- 30 .6 3% ) >CK(- 4 7.5 0 % ) >M0 +CK(- 6 1.88% )。

不同时间内家兔尿液中乌头碱代谢产物的研究

首次采用LC/ESI-MSn方法对乌头碱灌胃给药后不同时间内家兔尿液中的乌头碱代谢产物进对比研究。经与空白尿样对照发现,在0~4h和4~8h两个时间段,家兔尿液中除乌头碱(AC)原形外,均含有相同的代谢产物,但相对含量差别很大。通过总离子流色谱图(TIC)可以发现3个主要代谢产物(M1,M2,M4)。分别测定了各代谢产物的准分子离子及其各级碎片离子,与AC在ESI-MSn条件下的质谱碎裂规律相比较,并参考AC体内代谢文献,推断尿液中的主要代谢产物M1为16-O-去甲基乌头碱;M2和M4的m/z均为616,为同分异构体,结构还需要进一步的确认。

乌头碱在家兔肠道内代谢产物的LC/ESI-MSn研究

采用LC/ESI-MSn的方法对家兔肠道内的乌头碱代谢产物进行研究,经与空白组比较发现,给药后家兔小肠内容物中新增加6个化合物峰(M1～M6),盲肠内容物中新增加5个化合物峰(M2～M6),粪便中新增加2个化合物峰(M3、M4). 分别测定各化合物的准分子离子及各级串联碎片离子,并与标准品的质谱断裂规律进行比较,同时参考文献,推断肠道内化合物M1为16-O-去甲基-8-O-去乙酰基乌头碱,M2为8-O-去乙酰基乌头碱,M3为16-O-去甲基乌头碱,M4为乌头碱(AC),M5为去氧乌头碱,为印乌头碱。

卫星高度计资料在海洋潮汐研究中的应用

本文依据收集到的392个地面验潮站8个主要分潮（M2、S2、K1、O1、N2、K2、P1及Q1）的调和常数，对现有7个全球大洋潮汐模式的准确度进行了检验，结果显示各模式在深海区域均达到了比较高的准确度，相互之间差别也不大。经验模式GOT00和CSR4.0、同化模式NAO99、反演同化模式TPXO7.0、数值同化模式FES2002和FES2004的M2分潮均方根偏差在3 cm左右，其它分潮（S2、K1、O1、N2、K2、P1及Q1）大约在1～2 cm。本文还依据中国近海18个岛屿的调和常数对其中的5个大洋潮汐模式的准确度进行了检验，结果表明，M2分潮均方根偏差在6～14 cm，明显高于大洋部分的偏差，其中日本国家天文台的潮汐模式NAO99在中国近海的结果相对较准确。 我们利用1992年8月至2008年8月的TOPEX/POSEIDON和JASON-1(T/P-J)卫星高度计资料，对沿卫星轨道的302816个站点进行了14个分潮的潮汐调和分析，得到了全球大洋潮汐的8个主要分潮以及2个气象分潮Sa、Ssa的经验同潮图。主要结果有：（1）各分潮在卫星上升轨道与下降轨道的交叉点(约7000个)相关性分析表明：M2分潮的振幅和迟角的相关系数很高（分别为0.9965和0.9961）；S2，K1，O1和Sa分潮也有较好的相关性（相关系数为0.94～0.99）；（2）该结果与392地面个验潮站吻合较好，其中M2分潮的振幅、迟角和向量的均方根偏差分别为：1.73 cm，2.340和2.93 cm；S2，K1和O1分潮的振幅、迟角和向量的均方根偏差为1 cm左右，5.250～7.270和1.5～2.1 cm，该精度与最近几年国际上的主要大洋潮汐模式的准确度相近；（3）首次通过卫星资料获得了Sa、Ssa分潮的同潮图。周期为1年的Sa分潮与大洋105个地面站相比，振幅、迟角和向量的均方根偏差分别为1.50 cm、18.360和2.16 cm。在此基础上，进一步分析了构成Sa、Ssa气象分潮的两个主要因素（海水密度以及海面气压）在全球的分布。 在T/P-J等卫星资料无法覆盖到南大洋和北冰洋，本文利用Princeton Ocean Model（POM）进行了数值模拟，模拟结果与162个地面实测站（其中南大洋30个，北冰洋132个）的观测比较一致。基于卫星资料分析的结果和数值模拟结果合并得到了全球大洋的8个主要分潮同潮图。在此基础上通过全球潮汐能量耗散的计算得到潮能通量的分布，并得到全球M2、S2、K1和O1分潮的潮汐能量耗散率为2.431TW、0.401TW、0.336TW和0.176TW。 本文还利用卫星资料对南海潮汐进行了研究，在中国南海，获得了主要的半日潮、全日潮、四分日分潮和长周期分潮（M2，S2，N2，K2，K1，O1，P1，Q1，M4, MS4，Sa, Ssa）的经验同潮图。与南海沿岸94个地面验潮站的数据符合得比较好，M2，S2，K1及O1等4个主要分潮的平均振幅差为2～4 cm，均方根偏差分别是9～11 cm.其它4个主要分潮N2，K2，P1，Q1的平均振幅差为1～2 cm，均方根偏差为2～4 cm。此外，本文还利用卫星高度计资料潮汐分析结果沿卫星轨道进行高通滤波，分离得出中国近海的M2，S2，K1及O1分潮的内潮信息。

两种海藻提取物的化学成分和生物活性的研究及其应用

本论文的研究工作由两部分组成，第一部分研究了海带（Laminaria japonica）水提取物中的活性物质，并研究了提取物对蔬菜促生长的影响及其作用机制。第二部分对三列凹顶藻(Laurencia tristicha)乙醇提取物的乙酸乙酯相进行了活性筛选和化学成分研究，并对其中分离得到的单体化合物进行了生物活性筛选。 第一部分主要以中国人工养殖的海带为原料，使用与海藻多糖生产相结合的提取技术并浓缩其中的有效成分。对浓缩提取物进行了蔬菜的农田效果实验，并对作物抗旱性能的增加、作物硝酸盐积累的减少、作物品质的改善、以及作物抵抗病毒病的能力等影响进行了作用机制方面的研究。海藻浓缩提取物进行的农田效果实验表明：作物抗旱型相对含水量RWC值在92%~94%之间；病毒病的防治效果最高可达到91%；作物的品质有明显的改善，最重要的是首次发现海藻提取物有降低蔬菜中硝酸盐的含量（硝酸盐的含量是与有机蔬菜区别的重要指标之一）的作用。该部分研究工作的创新性主要体现在：（1）首次在国内外提出和采用与海藻多糖生产相结合的提取技术。该技术的应用不但减少了提取成本，使工业化生产成为可能,更重要的是使我国的海藻工业生产可能实现高值化和开辟综合利用的新途径。（2）首次发现海藻中的小分子海藻多糖具有和细胞激动素、甜菜碱、植物生长素等活性物质同样的生物活性。 第二部分的研究是在查阅了大量的近20年来国内外有关红藻凹顶藻中化学成分研究的相关文献的基础上，对凹顶藻中的次生代谢产物进行了综述。该论文主要是通过对红藻三列凹顶藻的95%乙醇提取物的乙酸乙酯相进行化学成分分析和生物活性筛选以期能够发现具有药用前景的活性先导化合物。 为了寻找具有生物活性的化合物，我们对采自我国南海硇洲岛海域的红藻三列凹顶藻的95%乙醇提取物的乙酸乙酯相进行了活性筛选。采用MTT法对其在KB细胞株、Bel-7402细胞株、PC-3M细胞株、MCF-7细胞株、Ketr-3细胞株模型上进行了细胞毒活性测试；采用酶模型对其进行了Na+,K+-ATPase的抑制活性测试；采用MTT法对其在犬主动脉血管模型上进行了血管平滑肌细胞增殖抑制活性测试；结果表明，三列凹顶藻的95%乙醇提取物的乙酸乙酯相对Na+,K+-ATPase和犬血管平滑肌细胞增殖具有一定的抑制活性。 利用正相和反相色谱、Sephadex LH-20色谱以及反相HPLC等手段进行分离纯化，从我国南海海域的红藻三列凹顶藻中分离得到33种化学成分，通过波谱学方法（IR、MS、NMR）以及X-ray单晶衍射试验对其化学结构进行了确证，其中化合物L1~L8为新结构化合物，化合物L5为具有新骨架的全新结构化合物，化合物L9~L13为新天然产物，化合物L18和L22系首次从海洋生物中获得，所有化合物均为首次从该属海藻中得到。新化合物L1~L8均为倍半萜类化合物，命名分别为：(1R,3R)-(-)-3-(3-hydroxy-4-methylphenyl)- 1,3-dimethyl–2-methylidene cyclopentanol (L1), (1R,3R)-(-)-3-(4-methylphenyl)-1,3-dimethyl-2-methylidenecyclopentanol (L2)， (1R, 3R)-(-)-3-(2-hydroxy-4-methylphenyl)-1,3-dimethyl–2–methylidenecyclopentanol (L3)，(+)-(1S,2R)–2-(3–hydroxy–4–methylphenyl)-1,2-[3.1.0]bicy-clohexane (L4)，()-(1S,2R) -5-hydroxy–6–methyl-spiro-dihydrobenzofuran-2(3H),2-{1-methyl-[3.1.0]bicyclohexane} (L5), (+)-6-methyl-2-(p-tolyl)hept-4-en-2,6-diol (L6)，(3R,3aS,8bS)-(-)-2,3,3a,8b–tetrahydro–7-bromo – 3 a– hydroxymethyl - 3, 6, 8b - trimethyl-1H- cyclopenta[b] benzofuran (L7 )，(3R, 3aS, 8bS) - (-) - 2,3,3a,8b–tetrahydro–3 a–hydroxymethyl-3,6,8b -trimethyl -1H – cyclopenta [b] benzofuran (L8)。25个已知结构化合物确定为：(+)-(1R,2R)-4-bromo-1,5, 9–trimethyl–12– methylidene–8–oxa-tricyclo[7.2.1.02]dodeca-2,4,6-triene (L9)，(3S,3aR,8bS)-(-)-2,3,3a, 8b– tetra -hydro–7-bromo–3–hydroxy-3,3a,6,8b-tetramethyl-1H-cyclopenta[b]benzofu- ran (L10 )，(3R, 3aR, 8bS) - (-) - 2, 3, 3a, 8b – tetrahydro – 7 - bromo – 3 – hydroxy - 3,3a,6,8b - tetramethyl - 1H - cyclopenta [b] benzofuran (L11 )，(3S,3aR,8bS) - (-) - 2, 3, 3a, 8b – tetrahydro –3–hydroxy -3, 3a, 6, 8b - tetramethyl-1H-cyclopenta[b]benzofuran (L12 )， ( 3aR, 8bS) - (-) - 3a,8b –dihydro–7 - bromo – 3, 3a, 6, 8b - tetramethyl - 1H - cyclopenta[b]benzofuran (L13 )，aplysinol (L14 ) ，aplysin (L15)，laurebiphenyl (L16)，johnstonol (L17)，gossonorol (L18)，7,10-epoxy-ar- bisabol-11-ol (L19)，10-epi-7,10-epoxyarbisabol-11-ol (L20) 3β-hydroxy- 5α, 6α-epoxy- β- ionone (L21 )，3β-hydroxy-5β,6β-epoxy-β-ionone (L22 )，胆甾醇 (L23 )，胆甾-5-烯-3β,7α二醇胆甾-5-烯-3β,7α二醇 (L24)，β-谷甾醇 (L25)，叶绿醇 (L26 )，玉米黄素 (L27 )，对羟基苯甲醛 (L28 )，3-吲哚甲醛 (L29 )，1-O-十六烷酰基-3-O-β-D-吡喃半乳糖基-丙三醇(L30 )，1-O-十八烷酰基-3-O-β-D-吡喃半乳糖基-丙三醇 (L31 )，丙三醇-1-软脂酸单酯 (L32 )，正十六碳酸 (L33 )。 采用MTT法对其中23个单体化合物在Bel-7402细胞株、BGC-823细胞株、A549细胞株、A2780细胞株、HCT-8细胞株和HELL细胞株模型上进行了细胞毒活性测试；采用MTT法对其中13个单体化合物在犬主动脉血管模型上进行了血管平滑肌细胞增殖抑制活性测试；结果表明，部分单体化合物显示出一定的生物活性。

三门峡宋家店黄土－古土壤序列的地层学研究及其古环境记录

The Sanmen Gorge area is located in the southernmost margin of the Chinese Loess Plateau with well developed eolian deposit sequence for the past 2.6 Ma, providing a key site for further understanding of the evolution history of the East Asian monsoon since late Pliocene. This study attempted to characterize the stratigraphy and paleoclimate record of the loess-paleosol sequence in the Songjiadian section. The work involved includes systematic field investigation, paleomagnetic and rock magnetic analyses, grain size and major chemical composition analyses, and multiple proxy measurements of magnetic susceptibility, color reflectance and the ratio of CBD-dissolvable iron to the total iron (FeD/FeT). By comparisons of the Songjiadian section with well studied loess sections in the west of the Sanmen Gorge, the spatial variations of the East Asian monsoon was evaluated for some periods during which typical loess or paleosols developed. The following conclusions have been obtained. 1. Stratigraphic correlation and paleomagnetic result demonstrate that the loess-paleosol sequence in the Songjiadian section was accumulated from 2.6Ma, and is generally a complete and continuous loess sequence. However, notable differences from type loess sections have been identified for a few loess and paleosol units, featured by absence or anomalous thickness in the Songjiadian section. 2. Magnetic susceptibility and chromaticity records clearly reveal the loess-paleosol cycles, and indicate that the Sanmen Gorge area has been warmer and more humid than the Lingtai and Jingchuan sections in the western central Loess Plateau since the Early Pleistocene. 3. Grain size distribution patterns are typical of eolian dust, and show a great similarity between various units of loess and paleosols, and between the S32 and the underlying Red Clay through the Songjiadian profile, suggesting the eolian origin for the loess, paleosols and the Red Clay. 4. Comparison of the FeD/FeT curves from different loess sections indicates a stronger chemical weathering in the Songjiadian section and notable enhancement around 1800, 800 and 600 ka BP, implying the strengthening of the East Asian monsoon during these periods. In contrast, it was weakened at 1100 ka BP. Generally, the summer monsoon shows a gradually decreasing trend during the entire Pleostocene, but the spatial pattern typified by an increasing trend in weathering intensity from north to south remained the same. 5. The loess unit L9 in the Songjiadian section displays two geomagnetic field anomalies with the midpoint ages of 0.917 and 0.875 Ma respectively, with a segment of 12 ka. They are demonstrated to be equivalent to the Santa Rosa and Kamikatsura geomagnetic excursions. 6. Magnetite is the main magnetic carrier for both loess and paleosols. Maghemite concentration is higher in paleosols than in loess, and is an important carrier for the enhanced magnetic susceptibility in paleosols. Magnetic fabric analysis suggests a dominant N-S wind direction prevailing in the L9 and L15, while the summer winds were dominantly in NNE-SSW direction during the S8 period, notably differing from previous studies.

A Note On Tidal Asymmetry In The Severn Estuary

A one-dimensional, non-linear numerical model is used to investigate the tidally averaged frictional stress and set-up of water level due to tidal asymmetry in the Severn Estuary; these quantities depend on the overtides in the region. A linearized model of the overtides is applied to calculations of the M4 currents in order to delineate the mechanisms responsible for their generation. The relative importance of individual non-linear mechanisms to the tidally averaged stress and set-up is determined; these mechanisms are interactions between tidal flow and changes in depth or breadth over a cross-section, frictional interaction between the tidal flow and Stokes drift, interaction between the tidal fluctuations in water depth and frictional retardation and non-linear advection.

An allosteric potentiator of M4 mAChR modulates hippocampal synaptic transmission.

Muscarinic acetylcholine receptors (mAChRs) provide viable targets for the treatment of multiple central nervous system disorders. We have used cheminformatics and medicinal chemistry to develop new, highly selective M₄ allosteric potentiators. VU10010, the lead compound, potentiates the M₄ response to acetylcholine 47-fold while having no activity at other mAChR subtypes. This compound binds to an allosteric site on the receptor and increases affinity for acetylcholine and coupling to G proteins. Whole-cell patch clamp recordings revealed that selective potentiation of M₄ with VU10010 increases carbachol-induced depression of transmission at excitatory but not inhibitory synapses in the hippocampus. The effect was not mimicked by an inactive analog of VU10010 and was absent in M₄ knockout mice. Selective regulation of excitatory transmission by M₄ suggests that targeting of individual mAChR subtypes could be used to differentially regulate specific aspects of mAChR modulation of function in this important forebrain structure.

The type IIb SN 2008ax: the nature of the progenitor

A source coincident with the position of the type IIb supernova (SN) 2008ax is identified in pre-explosion Hubble Space Telescope (HST) Wide Field Planetary Camera 2 observations in three optical filters. We identify and constrain two possible progenitor systems: (i) a single massive star that lost most of its hydrogen envelope through radiatively driven mass-loss processes, prior to exploding as a helium-rich Wolf-Rayet star with a residual hydrogen envelope, and (ii) an interacting binary in a low-mass cluster producing a stripped progenitor. Late time, high-resolution observations along with detailed modelling of the SN will be required to reveal the true nature of this progenitor star.

Spontaneous intramedullary apoptosis is present in disorders other than myelodysplasia

Myelodysplastic syndrome (MDS) is a group of hematopoietic disorders characterized by peripheral cytopenias in the presence of normo- or hypercellular dysplastic marrow. It has been suggested that premature intramedullary apoptosis may contribute to this phenomenon. We used terminal dUTP nick-end labeling (TUNEL) of bone marrow biopsy specimens and cytocentrifuge preparations from patients with MDS and a variety of other hematopoietic disorders to determine whether there is increased intramedullary apoptosis in MDS and whether any such effect is specific to MDS. TUNEL labeling of bone marrow from 24 patients with MDS revealed significant positivity in 10 of 11 patients with refractory anemia (RA), five of seven with RA and excess of blasts (RAEB), all three patients with RAEB in transformation (RAEB-t), and all three patients with RA with ring sideroblasts (RARS). The percent of positive cells ranged from 5 to 50% but showed no apparent correlation with morphological subtype. In a series of 29 patients with acute leukemia, 17 showed significant positivity (13 of 13 with myeloid disease: three M1, seven M2, one M3, two M4; four of 16 patients with lymphoid disease: one Burkitt-type lymphoma, two null acute leukemia, and one common acute lymphoid leukemia). Intramedullary apoptosis was associated with myeloid or early committed progenitor cells and was highest in secondary acute myeloid leukemia (AML). Normal bone marrow samples from 12 individuals showed no evidence of apoptosis. Our results suggest that an increased level of intramedullary apoptosis is apparent in both patients with MDS and those with AML; those with secondary AML have the highest levels. The relative absence of such findings in lymphoid malignancy suggests that the apoptotic pathways are different in this lineage.

The Well-Aligned Orbit of Wasp-84b: Evidence for Disk Migration of a Hot Jupiter

We report the sky-projected orbital obliquity (spin–orbit angle) of WASP-84 b, a 0.69MJup planet in an 8.52 day orbit around a G9V/K0V star, to be λ = −0.3 ± 1.7°. We obtain a true obliquity of ψ = 17.3 ± 7.7° from a measurement of the inclination of the stellar spin axis with respect to the sky plane. Due to the young age and the weak tidal forcing of the system, we suggest that the orbit of WASP-84b is unlikely to have both realigned and circularized from the misaligned and/or eccentric orbit likely to have arisen from high-eccentricity migration. Therefore we conclude that the planet probably migrated via interaction with the protoplanetary disk. This would make it the first “hot Jupiter” (P d < 10 ) to have been shown to have migrated via this pathway. Further, we argue that the distribution of obliquities for planets orbiting cool stars (Teff < 6250 K) suggests that high-eccentricity migration is an important pathway for the formation of short-orbit, giant planets.

Where are the mid-sized flares of ultracool M dwarfs?

We propose to observe the M8.5 dwarf SCR J1845-6357 with XMM-Newton EPIC for 60 ks. Very low-mass M dwarfs show a distinct drop in X-ray luminosity compared to slightly more massive M dwarfs. Surprisingly, this does not happen at the mass threshold where M dwarfs become fully convective (M4), but at significantly lower masses (M8). These very low mass stars seem to have a flaring behaviour different from earlier type stars: they display either occasional large flares or a very low-level "flickering" in their X-ray light curves, but not the canonical power-law flare-energy distribution observed for the Sun and other cool stars. Our aim is to collect a long-duration light curve for one of the most nearby ultracool dwarfs to quantify how its flare-energy distribution differs from earlier type stars.