987 resultados para Achnanthes cf. longipes


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We have cloned and characterized a cDNA encoding a putative ETS transcription factor, designated Cf-ets. The Cf-ets encodes a 406 amino acid protein containing a conserved ETS domain and a Pointed domain. Phylogenetic analysis revealed that Cf-ets belongs to the ESE group of ETS transcription factor family. Real-time PCR analysis of Cf-ets expression in adult sea scallop tissues revealed that Cf-ets was expressed mainly in gill and hemocytes, in a constitutive manner. Cf-ets mRNA level in hemocytes increased drastically after microbial challenge indicated its indispensable role in the anti-infection process. Simultaneously, the circulating hemocyte number decreased. In mammals, most ETS transcription factors play indispensable roles in blood cell differentiation and linage commitment during hematopoisis. Cf-ets is therefore likely to be a potential biomarker for hematopoiesis studies in scallops. (C) 2009 Elsevier Ltd. All rights reserved.

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The distribution of iodine in various biological macromolecules in Sargassum kjellmanianum was studied using neutron activation analysis combined with chemical and biochemical separation techniques. The results indicate that iodine is mainly bound with protein, part of iodine with pigment and polyphenol, and little with polysaccharides, such as algin, fucoidan and cellulose. This result is significant for the mechanism of enriching iodine of algae and utilization of alga iodine.

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The serine proteases with clip domain are involved in various innate immune functions in invertebrate such as antimicrobial activity, cell adhesion, pattern recognition and regulation of the prophenoloxidase system. A serine protease with clip-domain cDNA (Cf SP) was obtained by Expressed sequence taggings (ESTs) method and rapid amplification of cDNA ends (RACE). The Cf SP full-length cDNA was of 1,152 bp, including a 5'-terminal untranslated region (UTR) of 63 bp, a 3'-terminal UTR of 81 bp with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, and an open reading frame of 1,008 bp encoding a polypeptide of 336 amino acids with a putative signal peptide of 19 amino acids. The deduced amino acid sequence of Cf SP contained an amino-terminal clip domain with three disulfide bonds formed six conserved Cys residues, a carboxyl-terminal trypsin-like domain with the conserved His-Asp-Ser catalytic triad, and a low complexity linker sequence. The Cf SP was strongly expressed in hemocytes and the mRNA expression of Cf SP was up-regulated and increased 3.2-fold and 2.6-fold at 16 h after injection of Vibrio anguillarum and Micrococcus luteus. The results suggested that Cf SP gene might be involved in immune response of Gram-negative and Gram-positive microbial infection in scallop.

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为揭示渤海沉积物中氮的生物地球化学循环过程,本文应用自然粒度下的分级分离浸取方法首次对渤海沉积物中氮的形态进行了研究,获得了氮形态分布的地球化学特征;将沉积物氮中可转化和非转化部分定量区别开,并对可转化态中各形态氮对其循环贡献的大小进行了评估;结合底栖生物的分布初步探计了沉积物中氮与生物生产的关系及底栖生物对氮循环的影响。得到的主要结论包括:渤海沉积物中氮的形态分布特征及其控制因素。表层沉积物中IEF-N、CF-N、IMOF-N和OSF-N占TN的比例分别为3.67%,0.31%,0.42%和26.45%,OSF-N是可转化态氮的优势形态。IEF-N 中NH_4~+和NO_3~-具有不同的成岩机制:NH_2~+主要受OC、Es和粘土矿物性质影响,NO_3~-与水体分布密切相关。CF-N含量最小,主要受沉积环境pH值的影响。IMOF-N主要由NH_4~+在Fe~(3+)上的吸附形成,受沉积物的氧化还原环境控制。OSF-N除与物质来源有关外,受到粘土矿物性质及沉积物粒度的影响。Fe、Mn和Co对IEF-N和IMOF-N的成岩作用影响明显,Cu、Pb和Mo对OSF-N的分布产生影响,二者作用的机理不同。表层样中,约69.15%的氮经过早期成岩作用而埋藏,短期内不再参与循环。氮的埋藏通量与沉积物聚积速率呈显著正相关,同时受温度、Eh、OC、盐度、硫化物含量等因素影响。沉积物中C/N和N/P均呈现异常的低值,前者主要是由于沉积物中保留了大量的无机氮,后者主要因为陆地排放大量磷入海以及磷的埋藏效率高于氮所致。柱状样中,IEF-N基本随深度减小,IMOF-N随深度有突变现象,OSF-N随深度的变化表明了矿化作用进行的程度。对沉积物中生源要素分解速率常数有:N>P>C>Si。表层沉积物中可转化态氮占总氮的比例高于深层沉积物。OC/ON随深度减小表明沉积物通过某种机制富集了有机氮。各形态氮在氮循环中作用及渤海氮循环收支。对渤海沉积物中可转化态氮的量进行了估算,IEF-N、CF-N、IMOF-N和OSF-N分别为3.657 * 10~8kg,2.794 * 10~7 kg,3.832 * 10~7kg和2.372平共处* 10~9kg;结合室内模拟的氮的界面交换通量,估算其完全释放所需的时间分别为2.15a,0.16a,0.225a和13.94a。各形态氮释放的顺序与其结合牢固程度一致,即IEF-N>CF-N >IMOF-N>OSF-N,其对界面交换的贡献大小则随时间尺度大小发生变化:随时间尺度增加,IEF-N、CF-N、IMOF-N的贡献逐渐减小,OSF-N的贡献逐渐增大,当时间尺度大到足以使四态氮完全释放时,其贡献的大小与各形态氮的量一致即OSF-N(84.6%)>IEF-N(13.0%)>IMOF-N(1.4%)>CF-N(1.0%)。非转化态氮占总氮的 69.15%,其中由于颗粒物包裹导致的“非转化态”氮为49%,说明粒度的影响非常重要。IEF-N和OSF-N主要存在于颗粒物质外层,是循环的主要参与者,CF-N和IMOF-N绝大部分在内层,对循环的贡献很小。水体中再循环的氮对初级生产力的贡献(74.4%)比沉积物中再循环氮的贡献 (26.1)大得多,二者对生态系统的作用不同,水体再生的营养盐通常在较长的时间尺度上维持初级生产力的平衡,而沉积物中的再生则在很短的时间内通过强烈的混合作用提高初级生产力。沉积物中氮与生物生产的关系及底栖生物对沉积物氮循环的影响。IEF-N和OSF-N的分布均与初级生产力以及浮游植物个体数量的分布具有一定的相似性。沉积物中的IEF-N的作用相当于一个氮营养盐的“储存库”对初级生产力产生影响,其作用机制类似于水体富营养化的正反馈机制。IEF-N能对赤潮的发生起加速作用。底栖生物的分布与氮形态分布具有正的相关性:莱洲湾内IEF-N和OSF-N的分布与该区域高生物量和高密度的大型底栖动物分布一致,说明在底栖生物活动活跃的区域营养盐的再生和流动是高效而迅速的。生物扰动能加速矿化作用的进行,使沉积物在一定深度范围内NH_4~+含量增加,大型底栖动物的灌溉作用使NO_3~-在深层仍有较高的分布。底栖生物的不同种群对营养盐变化的响应不同。

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本论文的目的是研究几种病原菌口服疫苗接种鱼类的免疫效果,并从常见病原菌株中筛选几个具有较好保护效果的蛋白抗原,利用口服免疫的方式,接种养殖动物,并检测免疫效果。 以10号白油为有机溶剂,采用搅拌与均浆方法制备鳗弧菌M3和SMP1的油乳化二价疫苗,用饵料包埋后以口服途径免疫养殖大菱鲆,评价免疫大菱鲆的免疫应答和疫苗的保护效果。结果显示,以油乳化和未油乳化疫苗分别连续口服免疫大菱鲆一周后,在后肠组织,乳化疫苗刺激产生的非特异性活力、特异性抗体水平均高于未乳化疫苗;而在血清,两种疫苗引起的两种酶的活力、SMP1抗体水平没有变化,但在乳化疫苗免疫的大菱鲆检测到明显高于未免疫对照大菱鲆的M3抗体水平。大菱鲆后肠组织原位杂交结果显示,口服免疫的大菱鲆后肠褶皱有IgM抗体的产生和分布。其中,乳化疫苗免疫大菱鲆的IgM抗体的产生和分布水平高于未乳化疫苗免疫的大菱鲆。攻毒实验显示,乳化疫苗免疫的大菱鲆对M3和SMP1的感染分别获得100%和50%的免疫保护率,而未乳化疫苗获得的免疫保护率分别为57.9%和0%,表明乳化疫苗比未乳化疫苗更有效地保护大菱鲆、抵抗病原的感染。在乳化疫苗免疫持续期的研究中,免疫的大菱鲆后肠在免疫后120天仍能检测到抗体效价,在免疫后90天还能观察到一定的免疫保护效果。免疫30天、60天、90天和120天的大菱鲆分别获得100%、66.7%、36.7%和13.3%的免疫保护力。 以鳗弧菌M3和SMP1、链球菌CF迟缓爱德华菌SMW7作为细菌抗原制备油乳化多价口服疫苗和轮虫携带疫苗,口服途径免疫养殖大菱鲆与大菱鲆初孵仔鱼。结果显示,在免疫大菱鲆后肠可检测到抗M3抗体水平的提高(P<0.05),而在其胆汁、鳃、中肠、体表黏液、前肠与血清中抗体效价变化与对照组没有显示出差异;没有检测到免疫大菱鲆后肠抗SMP1、SMW7、CF体效价。M3浸泡攻毒实验显示,口服免疫的大菱鲆获得了100%的免疫保护力;在M3注射攻毒和SMP1、CFSMW7浸泡攻毒大菱鲆的实验中,在每个攻毒组中,免疫组大菱鲆开始死亡的时间都要比对照组有不同程度的延迟,但攻毒大菱鲆都发生死亡,不能显示出与对照组的差异。轮虫携带免疫的结果显示,免疫的大菱鲆初孵仔鱼并未获得较好的保护效果,与对照大菱鲆没有体现出差异。 从致病性病嗜水气单胞菌(Aeromonas hydrophila)LSA34克隆并表达ahaI基因和gapA基因,从迟缓爱德华菌(Edwardsiella tarda)LSE40克隆并表达eseB,将所得蛋白分别通过腹腔注射途径免疫大菱鲆,检测蛋白的免疫原性和免疫保护。结果在免疫后7天就可以检测到AhaI、GapA蛋白免疫组大菱鲆产生的抗体,至第40天可以检测到明显的保护性抗体,之后抗体效价增加明显,直至第60天时达到最高值。EseB免疫的大菱鲆第一次免疫后15天就有较高的抗体效价产生,明显高于对照组大菱鲆血清抗体效价,到距第一次免疫60天时,抗体效价达到最高值。攻毒实验显示,与对照组相比,AhaI免疫组和GapA免疫组对LSA34感染的免疫保护力分别为80%和100%;AhaI免疫组和GapA免疫组对LSE40感染的免疫保护力分别为30%和10%。,而对照组牙鲆对人工攻毒不具有保护力。以AhaI和GapA作为疫苗免疫大菱鲆,使大菱鲆获得了对嗜水气单胞菌LSA34较高的免疫保护;而对迟缓爱德华氏菌LSE40的交叉保护能力没有明显提高。EseB免疫的大菱鲆在攻毒实验中并没有显示出较好的保护效果,与对照组相比,只是在死亡时间上有所延迟。 以从致病性嗜水气单胞菌中克隆的ahaI和gapA基因表达出的蛋白为蛋白抗原制备油乳化疫苗,用饵料包埋后以口服途径免疫养殖牙鲆,评价免疫牙鲆的免疫应答和疫苗的保护效果。结果显示,以油乳化和未油乳化疫苗分别免疫牙鲆一周后,在后肠组织,AhaI和GapA乳化疫苗免疫组牙鲆检测到抗体,且分别高于AhaI和GapA未乳化疫苗免疫的牙鲆;而在血清,GapA的两种疫苗引起的GapA抗体水平没有变化;但在AhaI乳化疫苗免疫的牙鲆第21天和第35天的血清中检测到高于未免疫对照牙鲆的AhaI抗体水平,AhaI未乳化疫苗免疫牙鲆血清对照组相比没有检测到AhaI抗体水平的变化。

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长期、定点、连续测量海洋环境参数,尤其是从海洋表面到海底的垂直剖面的监测一直以来大都是由船只完成,耗费大量的人力和财力。“海浪驱动自持式海洋要素垂直剖面测量系统”(简称“海马”)利用海洋无时不在的波浪能,驱动滑行器单方向下潜运动,直达海底或程序设定的预定深度,在控制系统作用下,滑行器依靠自身的浮力匀速上浮, 并在此过程中,完成海洋要素的自动测量和存储。 当今海洋仪器大多采用“闪存”来存储数据,主要有RS-232串口和并型口的CF(Compact Flash)卡两种形式。但是两种接口都有一定的缺陷:CF不能和PC机直接通信,必须通过转接口才能将数据传送到PC机上;而RS-232接口虽然可以和PC机直接通信,但是由于其传输速度较慢,不利于大量数据的传输。由于上述两种接口的缺点,“海马”采用U盘来实现数据的存储。 USB接口不仅可以和PC机直接通信,而且具有使用方便,数据传输率高,又支持即插即用等特点,但由于USB接口协议复杂,涉及的方面广,特别是软件种类比较多,而且USB芯片种类繁多,使得USB设备的开发非常困难。 本文设计的USB(Universal Serial Bus)接口电路以单片机AT89C51以及CYPRESS公司生产的USB接口芯片SL811HS为核心,结合了随机存储芯片HY62256以及看门狗芯片X25165。在介绍了SL811HS控制器芯片的主要特点的基础上,重点阐述了利用这一芯片在C语言的编程控制之下如何识别U盘的插入和拔出,以及如何将单片机的数据按协议规定写入U盘,其中的协议包括FAT文件协议,USB协议和UFI命令协议。 本系统实现了单片机对U盘的数据存储,速度快,存储容量大,数据读取方便,直观明了,系统工作安全可靠,抗干扰能力强,可扩展性大,而且针对下位机设计的串口协议简单,可以满足“海马”海量数据的存储要求。

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本文系统研究了渤海南部海域沉积物-海水界面附近(包括上覆水、悬浮颗粒物和沉积物)P、Si的赋存形态及其生物地球化学过程。其特色在于提出了“自然粒度下形态研究”的概念,探讨了能真正参与循环的P、Si及其控制关键环节,为渤海资源特别是生物资源的可持续利用战略的制定提供理论基础。得到的主要结论包括:研究了渤海南部海域覆水、悬浮颗粒物中P、Si的变异特征。上覆水体PO_4-P、SiO_3-Si的平均含量均低于大洋底层水PO_4-P、SiO_3-Si的平均含量。悬浮颗粒物中TIP、BP的来源和循环控制机制不同,TISi、BSi有一定的相似性。稀释作用和表层沉积物中可交换态P、Si的循环控制上覆水体中P、Si的地球化学行为。颗粒物中TIP、TISi的行为受离子交换和化学吸附过程影响,其中化学吸附可能与Fe(III)的氧化物有关;生物过程对颗粒物中生源P、Si的地球化学行为有重要影响。渤海南部海域沉积物P、Si的分布特征及其成岩过程研究表明。表层沉积物可交换态磷中,OSF-P是磷的优势赋存形态,占总磷的10.7%;CF-Si是硅的优势赋存形态,占总硅的0.05%。 不同形态P的成岩过程有一定的相似性。TSi与其它相中的Si呈负相关或不呈显著相关,且可交换态Si的量仅占总Si的0.12%以下,说明以往采用测定总Si含量来研究Si的生物地球化学过程不可能得出有价值的信息。IMOF-P、OSF-P、IMOF-Si、CF-Si在P、Si的生物地球化学循环中有重要作用。CaCO_3、Fe(III)和Corg等对P、Si界面循环有重要影响,有机质的钙化导OSF-P的矿化作用而释放P;Fe(III)的还原引起IMOF-P, CF-P和CF-Si对P、Si的释放。Corg的成岩过程对CF-Si有影响。约79%的BP和75%的BSi沉积后转化为相对稳定状态,在较短时间内不再参与循环。柱状沉积物中,OSF-P和CF-P之间存在沉积转化。CF-Si呈双指数分布。P、Si在表层沉积物中垂向分布的差异,表明底栖生物扰动对加强界面P、Si交换的作用。室内模拟沉积物-海水界面附近P、Si交换过程表明,P、Si在沉积物、上覆海水间的交换通量分别为0.8μ mol/ (m~2 · h)。P、Si的埋藏与释放主要受OSF-P、IMOF-Si 和平共处BSi的影响。对渤海P、Si年循环的估算显示,P在渤海湾、莱州湾的年循环量达30.9 * 10~5kg 和13.8 * 10~5kg, Si则分别为22.8 * 10~7 kg和15.5 * 10~7 kg,这其中沉积物向上覆海水扩散的P占87.7%和87.0%, Si占22.4%和14.2%。就整个渤海而言,沉积物向海水释放的磷、硅在其总循环中分别占88.7%和34.0%,所以沉积物-海水界面过程对磷、硅在渤海的生物地球化学循环有重要影响,是渤海P、Si循环的关键控制过程之一。

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The chemical species of iodine in seven marine algae Codium fragile, Ulva pertusa, Monostroma nitidum, Gracilaria confervoides, Sargassum Kjellmanianum, Dictyopteris divaricata and Laminaria japonica were studied using neutron activation analysis combined with chemical separation. The contents of total iodine, water-soluble iodine, soluble organic iodine, I- and IO3- were determined. The results indicate that the chemical species and contents of iodine in various algae are remarkably different. The highest iodine content of 734 mg/kg (wet basis) was found in Laminaria japonica, with 99.2% of the total iodine being water soluble. The iodine contents of the other six algae are lower and soluble iodine makes up 16-41% of the total. In the aqueous leachate, iodine is mainly I-, which amounts to 61-93% of total water-soluble iodine; the percentages of organic iodine making up 5.5-37.4%, while the contents of IO3- are the lowest, 1.4-4.5%. This result suggests that the mechanism of iodine enrichment is different for various algae and that its bioavailability varies as well. (C) 1997 Elsevier Science B.V.

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The increasing trend of air temperature along with the climate warming has been accepted gradual-ly by scientists and by the general public. Qinghai-Xizang Plateau, a unique geographic unit due to high-altitude climate, is one of the most susceptible regions to climate warming. Its ecosystem is very fragile and sensi-tive to climate change. In order to get a better understanding of the impacts of climate warming on the nutrient contents of herbage grown in Qinghai-Xizang Plateau, a simulative study was implemented at Daban Moutain by using temperature differences resulted from sites selected at different altitudes and nutrient contents and in vitro digestibility were determined for assessing the quality of the grown herbage. There were significant downtrends in crude protein (CP), ether extract (EE) and nitrogen free extract (NFE) contents of herbage along with the increase of temperature. It had a positive correlation between temperature and content of acid detergent fibre (ADF), acid detergent lignin (ADL) in herbage. In vitro digestibility of herbage decreased along with the in-crease of temperature. The results of this study indicated that climate warming significantly influence nutrient contents and in vitro digestibility of herbage grown in Qinghai-Xizang Plateau. It is suggested that the future climate warming especially the gradual rise of the night temperature could cause negative effect on herbage quality grown in Qinghai-Xizang Plateau by decreasing CP, EE, and NFE contents and increasing some indi-gestible ingredients such as crude fibre (CF), neutral detergent fibre (NDF), ADF, and ADL. This, conse-quently, decreases the ruminant assimilation ability.

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表观光合量子效率(AQY);光系统Ⅱ(PSⅡ ) 的光化学效率(Fv/Fm );光合作用的光抑制;日变化 摘要:用便携式ADC 光合气体分析系统和便携式CF-1000 荧光仪对青海和上海的同一植物和不同植物叶片光合作用的光抑制进行了测定。结果表明, 两地在晴天强光下, 中午植物叶片光系统Ⅱ(PSⅡ ) 的光化学效率(Fv/Fm ) 和表观光合量子效率(AQY) 的日变化比早晨低; 上海测定PSⅡ 的Fv/Fm 和AQ Y 的日变化比青海的下降幅度大。AQ Y 的日变化曲线比PSⅡ的Fv/Fm 低,AQ Y 降低的幅度比PSⅡ 的Fv/ Fm 大。两地植物均有不同程度的光合作用光抑制, 且上海比青海的大。

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The chlorophyll fluorescence in soybean leaves was observed by a portable fluorometer CF-1000 under field conditions. On clear days, F-0 increased while F, and F-v/F-m decreased gradually in the morning. At midday F-O reached its maximum while F-v and F-v/F-m reached their minimum. The reverse changes occurred in the afternoon. At dusk these parameters could return to levels near those at dawn. Following exposure to a strong sunlight for more than 3 h, the dark-recovery process displayed three phases: (1) slow increases in F-0, F-v and F-v/F-m within the first hour; (2) a faster decrease in F-0 and faster increases in F-v and F-v/F-m within subsequent two hours; (3) a slow decrease in F-0 and slow increases in F-v and F-v/F-m within the fourth hour. In comparison with darkness, weak irradiance had no stimulating effect on the recovery from photoinhibition. Hence the photoinhibition in soybean leaves is mainly the reflection of reversible inactivation of some photosystem 2 reaction centres, but not the result of D1 protein loss.

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探讨了基于分布式专家系统的超高压输电线路巡检机器人控制系统,给出了一种利用CUPS和C、VC++混合编程构成分布式专家系统作为机器人控制器的方法,并且提出了一种基于规则和证据的可信度(CF)的分布式专家系统的协调算法.经过试验论证,该控制方法能很好地实现超高压输电线路巡检机器人的作业功能。

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In this study, 172 mollusk assemblages from the Weinan loess section in the southeast of Loess Plateau, China, were identified quantitatively at relative high resolution. The results show: 1) the history and processes of paleoclimatic and paleoenvironmental changes in Weinan since the last 70 ka; 2) the characteristics of climatic changes during the period of the last glacial maximum (LGM); 3) the spatial pattern of paleoclimate variations at the south and middle parts of the Loess Plateau during the LGM period; 4) the timing of the last deglaciation and the return event of rapid climate change during the last deglaciation. The main conclusions are as follows: 1) 172 mollusk samples taken from the uppermost 9 m deposits cover the past 70 ka, which were sampled at the internals of 5 cm for S_0, 3 cm for L_(1-1) and L_(1-2), and 10 cm for L_(1-3), L_(1-4) and L_(1-5). Author analyzed quantitatively all individuals including broken pieces of snail shells, percentages of 15 species identified from 172 samples. Three main groups were determined according to the ecological requirement of each taxon. Based on the variations of three ecological groups and typical ecological species, The author intended to reconstruct the history of and processes of climate and environment since the last 70 ka in the Weinan region. The climate and environment in this region experienced the following changes: relative warm and humid stage from 67.5-20.3 cal. ka B.P., a period of forest-steppe or steppe developed; cold and arid stage from 20.3-15.5 cal. ka B.P., a dry steppe period, later wetter and colder; cold and humid period once time from 15.5 to 12.3 cal. ka B.P., a typical steppe or forest-steppe stage; cold and humid again from 12.3 cal. ka B.P. to 8.2 cal. ka B.P., a tropical steppe stage; warm and humid climate, a forest-steppe developed. 2) The climate during the period of the last glacial maximum (LGM) in Weinan was characterized by a general cold-humid condition, represented by occurrence of a number of the cool-humidiphilous mollusk species such as Gastocopta amigerella and Vallonia cf. pulchella in the section. 3) Comparison of the variations in abundance of Puncture orphana at Weinan with those at Luochuan and Changwu sections suggests that the summer monsoon intensity influenced differently at the three regions during the LGM period. The Weinan was weaker summer monsoon impact during all the period, the Luochuan was influenced occasionally, and Changwu was only a very short time affected, which indicated it might be located at the western margin of the summer monsoon influence during that period. 4) The ratio of thermo-humidiphilous mollusk group to cold-aridiphilous one shows an increase tendency at about 15 cal. ka B.P., reflecting the climate warming after the deglaciation in Weinan, which is approximately corresponding to the timing of warming period of the last deglaciation, found in the East Atlantic Ocean, the South China Sea and the Loess Plateau (indicated by the phytolith study). 5) A remarkable decrease in the number of thermo-humidiphilous and cool-humidiphilous mollusk species from 12.7 - 11.6 cal. ka B.P. indicates a cooling in climate and might be the reflection of the Younger Dryas event in Weinan. 6) Variations in the ratios of thermo-humidiphilous mollusk species to cold-aridiphilous ones reflect the climate instability in Holocene. There were four warm-humid periods (10-8.1 cal. ka B.P., 6.9-6.1 cal. ka B.P., 5.2-2.6cal. ka B.P., 1.6cal. ka B.P. to the present ) and three relative cold-arid periods (8.1-6.9 cal. ka B.P., 6.1-5.2 cal. ka B.P., 2.6-1.6 cal. ka B.P.), showing about a 1,000 year climatic oscillation.

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As a typical geological and environmental hazard, landslide has been causing more and more property and life losses. However, to predict its accurate occurring time is very difficult or even impossible due to landslide's complex nature. It has been realized that it is not a good solution to spend a lot of money to treat with and prevent landslide. The research trend is to study landslide's spatial distribution and predict its potential hazard zone under certain region and certain conditions. GIS(Geographical Information System) is a power tools for data management, spatial analysis based on reasonable spatial models and visualization. It is new and potential study field to do landslide hazard analysis and prediction based on GIS. This paper systematically studies the theory and methods for GIS based landslide hazard analysis. On the basis of project "Mountainous hazard study-landslide and debris flows" supported by Chinese Academy of Sciences and the former study foundation, this paper carries out model research, application, verification and model result analysis. The occurrence of landslide has its triggering factors. Landslide has its special landform and topographical feature which can be identify from field work and remote sensing image (aerial photo). Historical record of landslide is the key to predict the future behaviors of landslide. These are bases for landslide spatial data base construction. Based on the plenty of literatures reviews, the concept framework of model integration and unit combinations is formed. Two types of model, CF multiple regression model and landslide stability and hydrological distribution coupled model are bought forward. CF multiple regression model comes form statistics and possibility theory based on data. Data itself contains the uncertainty and random nature of landslide hazard, so it can be seen as a good method to study and understand landslide's complex feature and mechanics. CF multiple regression model integrates CF (landslide Certainty Factor) and multiple regression prediction model. CF can easily treat with the problems of data quantifying and combination of heteroecious data types. The combination of CF can assist to determine key landslide triggering factors which are then inputted into multiple regression model. CF regression model can provide better prediction results than traditional model. The process of landslide can be described and modeled by suitable physical and mechanical model. Landslide stability and hydrological distribution coupled model is such a physical deterministic model that can be easily used for landslide hazard analysis and prediction. It couples the general limit equilibrium method and hydrological distribution model based on DEM, and can be used as a effective approach to predict the occurrence of landslide under different precipitation conditions as well as landslide mechanics research. It can not only explain pre-existed landslides, but also predict the potential hazard region with environmental conditions changes. Finally, this paper carries out landslide hazard analysis and prediction in Yunnan Xiaojiang watershed, including landslide hazard sensitivity analysis and regression prediction model based on selected key factors, determining the relationship between landslide occurrence possibility and triggering factors. The result of landslide hazard analysis and prediction by coupled model is discussed in details. On the basis of model verification and validation, the modeling results are showing high accuracy and good applying potential in landslide research.

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A model is developed for predicting the resolution of interested component pair and calculating the optimum temperature programming condition in the comprehensive two-dimensional gas chromatography (GC x GC). Based on at least three isothermal runs, retention times and the peak widths at half-height on both dimensions are predicted for any kind of linear temperature-programmed run on the first dimension and isothermal runs on the second dimension. The calculation of the optimum temperature programming condition is based on the prediction of the resolution of "difficult-to-separate components" in a given mixture. The resolution of all the neighboring peaks on the first dimension is obtained by the predicted retention time and peak width on the first dimension, the resolution on the second dimension is calculated only for the adjacent components with un-enough resolution on the first dimension and eluted within a same modulation period on the second dimension. The optimum temperature programming condition is acquired when the resolutions of all components of interest by GC x GC separation meet the analytical requirement and the analysis time is the shortest. The validity of the model has been proven by using it to predict and optimize GC x GC temperature programming condition of an alkylpyridine mixture. (c) 2005 Elsevier B.V. All rights reserved.