Synthesis and pharmacokinetic property improvement of deuterated plinabulin 9

Plinabulin,a potent microtubule-targeting agent,is derived from marine natural diketopiperazine ‘phenylahistin'.To develop novel plinabulin analogue that could display better pharmacokinetic properties and less side effects,deuterated plinabulin 9 was synthesized and evaluated in vitro and in vivo.In comparison with plinabulin,in vivo pharmacokinetic studies indicated that the deuterated derivative 9 could alter blood circulation behavior obviously,which was proved by increased area under the plasma concentration-time curve(AUC_(0–∞)),reduced clearance(CL),and prolonged total body mean residence time(MRT).The derivative 9 also has higher inhibition rates against Bx PC-3,Jurkat and A-431 tumor cell lines as compared with its prototype plinabulin.Therefore,the deuterated compound 9 might be developed as a potential agent for different cancer treatments.     

基于RS和GIS的河西走廊风沙灾害风险评估

河西走廊位于中国西北干旱、半干旱区,受到周边沙漠和戈壁的影响,风沙灾害问题比较严重。依据灾害系统理论,从致灾因子危险性、孕灾环境脆弱性和承灾体易损性3个方面构建区域灾害风险评估体系和评估模型,对河西走廊风沙灾害风险进行评估。结果表明：（1）高风险地区主要分布在河西走廊内部的沙漠区,如酒泉市、玉门市、金塔县、高台县、临泽县以及武威市的北部地区,约占总面积的10.8%;（2）较高风险的地区主要分布在敦煌市、阿克塞哈萨克族自治县和河西走廊的北部,约占总面积的56.5%;（3）低风险地区位于河西走廊的东南部,该区在祁连山的天然屏障下,植被盖度高,雨水丰富;（4）作为风沙灾害的主体和对象,河西走廊的社会经济因素对风沙灾害风险的贡献率较低。而作为风沙灾害的物质基础和动力条件,沙源和风速仍是河西走廊风沙灾害风险的主要诱因;（5）经济发达城市在风沙灾害中具有更高的易损性,应该对城市邻近沙源进行重点防治。     

The antioxidant effects of complexes of tilapia fish skin collagen and different marine oligosaccharides

An excess of reactive oxygen species (ROS) leads to a variety of chronic health problems.As potent antioxidants, marine bioactive extracts containing oligosaccharides and peptides have been extensively studied.Recently, there is a growing interest in protein-polysaccharide complexes because of their potential uses in pharmaceutical and food industries.However, only few studies are available on the antioxidant activities of such complexes, in terms of their ROS scavenging capability.In this study, we combined different marine oligosaccharides (isolated and purified) with collagen peptides derived from tilapia fish skin, and evaluated the an-tioxidant activity of the marine peptide-oligosaccharide complexes vis-à-vis the activity of their original component molecules.Bio-chemical and cellular assays were performed to measure the scavenging effects on 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide radicals, and to evaluate the influences on the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in UV-induced photoaging models.The results indicated that the antioxidant activities of all the complexes were stronger than those of their individual components.Among the 11 complexes tested, two complexes, namely MA1000+CP and κ-ca3000+CP, turned out to be highly effective antioxidants.Although the detailed mechanisms of this improved scavenging ability are not fully understood, this work provides insights into the design of highly efficient peptide-oligosaccharide complexes for potential applications in pharmaceutical, cosmetics and food industries.     

Extraction,isolation and structural characterization of polysaccharides from a red alga <Emphasis Type="Italic">Gloiopeltis furcata</Emphasis>

Three kinds of polysaccharides:GFW,GFH and GFA,were sequentially extracted from a red alga Gloiopeltis furcatawith 25℃and 85℃water,and 60℃ 4%NaOHwater solution.Based on the defatted alga,the yields of the polysaccharide were57.9%,2.5%and 2.6%,respectively.Their monosaccharide compositions,average molecular weights and structural characters weredetermined by gas chromatography(GC),high performance liquid chromatography(HPLC),fourier transform infrared spectroscopy(FTIR)or13C-NMR spectroscopy.The results show...     

地电阻率观测各类干扰源的分析与研究

地电阻率观测是我国地震前兆监测的重要手段之一,目前已积累了大量的观测资料和强震震例。但随着农村经济的发展和城市现代化轨道交通设施的建设,使得部分地电台站观测环境发生较大变化,导致地电阻率前兆观测资料受到较强的干扰。本文通过对国内现有地电阻率观测资料的分析、干扰源的调研,研究了各类干扰产生的原因及识别方法。并根据已有的研究成果,对地电阻率观测抑制干扰的技术和方法及数据使用与处理提出了相应的建议。     

青海北巴颜喀拉成矿带基于专家证据权重法锑金矿资源潜力评价

青海北巴颜喀拉成矿带虽然总体研究程度低,但显示出巨大的找矿潜力,急需寻求新的找矿突破。利用前人的地质、矿产、化探等资料,建立了青海北巴颜喀拉成矿带基于GIS的空间数据库。在此基础上重新建立了研究区锑金矿区域找矿模型,其中主要找矿标志包括金水系沉积物异常、锑水系沉积物异常、砷水系沉积物异常、重砂异常、NW－NWW向线性构造和巴颜喀拉山群。采用作者提出的专家证据权重法,对研究区首次进行了基于GIS下的专家证据权重法矿产资源评价工作。据此重新圈定找矿远景区和找矿靶区,将后验概率大于0.001的区域作为找矿远景区,将后验概率大于0.005的区域作为找矿靶区;并依据找矿靶区内预测含矿区域后验概率二重积分大小,将找矿靶区的找矿潜力级别由高到低分别划分为A 、B 、C 3级,其中A级6处,B级10处,C级13处。     

The methane hydrate formation and the resource estimate resulting from free gas migration in seeping seafloor hydrate stability zone

It is a typical multiphase flow process for hydrate formation in seeping seafloor sediments. Free gas can not only be present but also take part in formation of hydrate. The volume fraction of free gas in local pore of hydrate stable zone (HSZ) influences the formation of hydrate in seeping seafloor area, and methane flux determines the abundance and resource of hydrate-bearing reservoirs. In this paper, a multiphase flow model including water (dissolved methane and salt)-free gas hydrate has been established to describe this kind of flow-transfer-reaction process where there exists a large scale of free gas migration and transform in seafloor pore. In the order of three different scenarios, the conversions among permeability, capillary pressure, phase saturations and salinity along with the formation of hydrate have been deducted. Furthermore, the influence of four sorts of free gas saturations and three classes of methane fluxes on hydrate formation and the resource has also been analyzed and compared. Based on the rules drawn from the simulation, and combined information gotten from drills in field, the methane hydrate(MH) formation in Shenhu area of South China Sea has been forecasted. It has been speculated that there may breed a moderate methane flux below this seafloor HSZ. If the flux is about 0.5 kg m⁻² a⁻¹, then it will go on to evolve about 2700 ka until the hydrate saturation in pore will arrive its peak (about 75%). Approximately 1.47 × 10⁹ m³ MH has been reckoned in this marine basin finally, is about 13 times over preliminary estimate.     

湖南漠滨金矿流体包裹体研究和成因探讨

对漠滨金矿流体包裹体的最新研究, 获得成矿流体物理化学参数: 平均均一温度为199.14℃, 平均盐度为6.01wt% (NaCl) , 平均密度为0.92 g/ cm3。据此估算, 漠滨金矿的平均成矿压力为 16.36 Mpa, 平均成矿深度为1.64 km。结合地质特征分析和前人的研究结果, 认为漠滨金矿属于造山型金矿床的浅成类型, 并推断漠滨金矿深部找矿潜力较小。     

Two pedogenic models for paleoclimatic records of magnetic susceptibility from Chinese and Siberian loess

The magnetic susceptibility (MS) of Chinese loess showing a general proportional relationship to pedogenic grade has been widely recognized and used for reconstruction of paleoclimate by Quaternary scientists. The in-situ pedogenic enhancement of ferrimagnetic content is normally believed to be the main reason for the increase of susceptibility in soil units. However, this pattern of high magnetic susceptibility in palaeosols, and low values in loess, are not replicated in some loess deposits. Siberian loess deposits display a completely opposite susceptibility behavior: high values in loess and low values in palaeosols. This inverse relationship has been explained by the idea that magnetic susceptibility is reflecting the magnitude of an aeolian ferrimagnetic component of consistent mineralogy, the grain size of which is related to average wind velocity. Our magnetic study of Siberian samples in this paper suggests that there are notable differences in magnetic properties between Siberian loess and developed palaeosols, not only in magnetic grain-size and concentration but also in magnetic mineralogy. This evidence is difficult to explain fully through variation in wind strength alone, but implies that the low magnetic susceptibility values in the Siberian paleosol units are a reflection, at least in part, of the alteration of the ferrimagnetic content by post-depositional processes. The Loess Plateau is a very arid area where potential evaporation is always higher than precipitation; pedogenesis occurs under dry oxidising conditions. The Siberian Kurtak region is located on the edge of the tundra where it is always wet and saturation during interglacials will lead to a reducing pedogenic environment. Ferrimagnetic minerals under this condition will be destroyed, resulting in lower magnetic susceptibility. Therefore, great care should be taken when using susceptibility values for paleoclimatic reconstruction.     

用遥感资料估算深层土壤水分的方法和模型

该文以热惯量法为基础,在EPPL7地理信息系统（GIS）的支持下,考虑土壤质地的影响,探讨了利用NOAA/AVHRR遥感资料估算深层土壤水分的方法和模型。结果表明:表层土壤水分与深层土壤水分之间有较好的非线性关系,可以用遥感得到的表层土壤水分去估算深层土壤水分,且效果优于直接分层建立统计模型。