122 resultados para Giunzioni, Incollaggi, Pin, Collar, Interferenza
Resumo:
由于人类活动所引起的地球大气层中温室气体的富集已导致全球地表平均温度在20 世纪升高了0.6 ¡æ,并预测在本世纪将上升1.4-5.8 ¡æ。气候变暖对陆地植物和生态系统产生深远影响,并已成为全球变化研究的重要议题。位于青藏高原东部的川西亚高山针叶林是研究气候变暖对陆地生态系统影响的重要森林类型。森林采伐迹地和人工云杉林下作为目前该区人工造林和森林更新的两种重要生境,二者截然不同的光环境对亚高山针叶林不同物种更新及森林动态有非常重要的影响。 本文以青藏高原东部亚高山针叶林几种主要森林树种为研究对象,采用开顶式增温法(OTCs)模拟气候变暖来研究增温对生长在两种不同光环境下(全光条件和林下低光环境)的几种幼苗早期生长和生理的影响,旨在从更新角度探讨亚高山针叶林生态系统不同树种对气候变暖在形态或生理上的响应差异,其研究结果可在一定程度上为预测气候变暖对亚高山针叶林物种组成和演替动态提供科学依据,同时也可为未来林业生产管理者提供科学指导。 1、与框外对照相比,OTCs 框内微环境发生了一些变化。OTCs 框内与框外对照气温年平均值分别为5.72 ¡æ和5.21 ¡æ,而地表温度年平均值分别为5.34 ¡æ和5.04 ¡æ,OTCs 使气温和地表年平均温度分别提高了0.51 ¡æ和0.34 ¡æ;OTCs框内空气湿度年平均值约高于框外对照,二者分别为90.4 %和85.3 %。 2、增温促进了三种幼苗生长和生物量的积累,但增温效果与幼苗种类及所处的光环境有关。无论在全光或林下低光条件下,增温条件下云杉幼苗株高、地径、分支数、总生物量及组分生物量(根、茎、叶重)都显著地增加;增温仅在全光条件下使红桦幼苗株高、地径、总生物量及组分生物量(根、茎、叶重)等参数显著地增加,而在林下低光条件下增温对幼苗生长和生物量积累的影响效果不明显;冷杉幼苗生长对增温的响应则与红桦幼苗相反,增温仅在林下低光条件下对冷杉幼苗生长和形态的影响才有明显的促进作用。 增温对三种幼苗的生物量分配模式产生了不同的影响,并且这种影响也与幼苗所处的光环境有关。无论在全光或林下低光环境下,增温都促使云杉幼苗将更多的生物量分配到植物地下部分,从而导致幼苗在增温条件下有更高的R/S 比;增温仅在林下低光条件下促使冷杉幼苗将更多的生物量投入到植物叶部,从而使幼苗R/S 比显著地降低;增温在全光条件下对红桦幼苗生物量分配的影响趋势与冷杉幼苗在低光条件下相似,即增温在全光条件下促使红桦幼苗分配更多的生物量到植物同化部分—叶部。 3、增温对亚高山针叶林生态系统中三种幼苗气体交换和生理表现的影响总体表现为正效应(Positive),即增温促进了几种幼苗的生理活动及其表现:(i)无论在全光或林下低光环境下,增温使三种幼苗的光合色素含量都有所增加;(ii)增温在一定程度上提高了三种使幼苗的PSII 光系统效率(Fv/Fm),从而使幼苗具有更强的光合电子传递活性;增温在一定程度使三种幼苗潜在的热耗散能力(NPQ)都有所增强,从而提高幼苗防御光氧化的能力;(iii)从研究结果来看,增温通过增加光合色素含量和表观量子效率等参数而促进幼苗的光合作用过程。总体来说增温对幼苗生理过程的影响效果与幼苗种类及所处的光环境有关,增温仅在全光条件下对红桦幼苗光合过程的影响才有明显的效果,而冷杉幼苗则相反,增温仅在低光条件下才对幼苗的生理过程有显著的影响。 4、增温对三种幼苗的抗氧化酶系统产生了一定的影响。从总体来说,增温使几种幼苗活性氧含量及膜脂过氧化作用降低,从而在一定程度上减轻了该区低温对植物生长的消极影响;增温倾向表明使三种幼苗体内抗氧化酶活性和非酶促作用有所提高,从而有利于维持活性氧代谢平衡。但增温影响效果与幼苗种类所处的光环境及抗氧化酶种类有关,增温对冷杉幼苗抗氧化酶活性的影响仅在林下低光环境下效果明显,而对红桦幼苗抗氧化酶活性的影响仅在全光条件下才有明显的效果。 总之,增温促进了亚高山针叶林生态系统中三种幼苗的生长和生理表现,但幼苗生长和生理对增温的响应随植物种类及所处的光环境不同而变化,这种响应差可能异赋予了不同植物种类在未来气候变暖背景下面对不同环境条件时具有不同的适应力和竞争优势,从而对亚高山针叶林生态系统物种组成和森林动态产生潜在的影响。 Enrichment of atmospheric greenhouse gases resulted from human activities suchas fossil fuel burning and deforestation has increased global mean temperature by 0.6¡æ in the 20th century and is predicted to increase it by 1.4-5.8 ¡æ. The globalwarming will have profound, long-term impacts on terrestrial plants and ecosystems.The ecoologcial consequences arising from global warming have also become thevery important issuses of global change research. The subalpine coniferous forests inthe eastern Qinghai-Tibet Plateau provide a natural laboratory for the studying theeffects of climate warming on terrestrial ecosystems. The light environment differssignificantly between clear-outs and spruce plantations, which is particularlyimportant for plant regeneration and forest dynamics in the subalpine coniferous forests. In this paper, the short-term effects of two levels of air temperature (ambient andwarmed) and light (full light and ca. 10% of full light regimes) on the early growthand physiology of Picea asperata, Abies faxoniana and Betula albo-sinensis seedlingswas determined using open-top chambers (OTCs). The aim of the present study wasto understand the differences between tree species in their responses to experimentalwarming from the perspective of regeneration. Our results could provide insights intothe effects of climate warming on community composition and regeneration behavior for the subalpine coniferous forest ecosystem processes, and provide scientificdirection for the production and management under future climate change. 1. The OTCs manipulation slightly altered thermal conditions during the growingseason compared with the outside chambers. The annual mean air temperature andsoil surface temperature was 5.72 and 5.34 ¡æ (within the chambers), and 5.21 and5.04 ¡æ (outside the chambers), respectively. The OTCs manipulation increased airtemperature and soil surface temperature by 0.51 and 0.34 ¡æ on average, respectively.Air relative humidity was slightly higher inside the OTCs compared with the controlplots, with 90.4 and 85.3 %, respectively. 2. Warming generally stimulated the growth and biomass accumulation of thethree tree species, but the effects of warming on growth and development variedbetween light conditions and species. Irrespective of light regimes, warmingsignificantly increased plant height, root collar diameter, total biomass, componentbiomass (stem, foliar and root biomass) and the number of branches in P. asperataseedlings; For A. faxoniana seedlings, significant effects of warming on all the tested parameters (plant height, root collar diameter, total biomass, and component biomass) were found only under low light conditions; In contrast, the growth responses of B.albo-sinensis seedlings to warming were found only under full light conditions. Warming had pronounced effects on the pattern of carbon allocation. Irrespectiveof light regimes, the P. asperata seedlings allocated relatively more biomass to rootsin responses to warming, which led to a higher R/S. Significant effects of warming onbiomass allocation were only found for the A. faxoniana seedlings grown under lowlight conditions, with significantly increased in leaf mass ratio (LMR) and decreasedin R/S in responses to warming manipulation. The carbon allocation responses of B.albo-sinensis seedling to warming under full light conditions were similar with theresponse of A. faxoniana seedlings grown under low light conditions. Warmingsignificantly decreased root mass ratio (RMR), and increased leaf mass ratio (LMR)and shoot/root biomass ratio (S/R) for the B. albo-sinensis seedlings grown under full light conditions. 3. Warming generally had a beneficial effect on physiological processes of dominant tree species in subalpine coniferous forest ecosystems: (i) Warming markedincreased the concentrations of photosynthetic pigments in both tree species, but theeffects of warming on photosynthetic pigments were greater under low lightconditions than under full light conditions for the two conifers; (ii) Warming tended toenhance the efficiency of PSII in terms of increase in Fv/Fm, which was related tohigher chloroplast electron transport activity; and enhance non-radiative energydissipation in terms of in increase in NPQ, which may reflect an increased capacity inpreventing photooxidation; (iii) Warming may enhance photosynthesis and advancephysiological activity in plants by increasing photosynthetic pigment concentration,the efficiency of PSII and apparent quantum yield (Φ) etc. From the results, theeffects of warming on seedlings’ physiological performance varied between lightenvironment and species. The effects of warming on photosynthesis performance of B.albo-sinesis seedlings were pronounced only under full light conditions, while thephysiological responses of A. faxoniana seedlings to warming were found only underthe 60-year plantation. These results provided further support for the observationsabove on growth responses of seedlings to warming. 4. Warming had marked effects on antioxidative systems of the three seedlings.Warming generally decreased H2O2 accumulation and the rate of O2- production, andalleviated degree of lipid peroxidation in terms of decreased MDA content, whichalleviated to some extent the negative effects of low temperature on the plant growthand development in this region; Warming tended to increase the activities ofantioxidative enzymes and stimulate the role of non-enzymatic AOS scavenging,which helped to create an balance in maintaining AOS metabolites for the threeseedlings. Nevertheless, the effects of warming on antioxidative defense systems werepronounced only under the 60-year plantation for the A. faxoniana seedlings. Incontrast, the marked effects of warming on antioxidative defense systems for the B.albo-sinesis seedlings were found only under the full light conditions. In sum, warming is considered to be generally positive in terms of growth andphysiological process. However, the responses of growth and physiology performanceto warming manipulation varied between species and light regimes. Competitive and adaptive relationships between tree species may be altered as a result of responsedifferences to warming manipulation, which is one mechanism by which globalwarming will alter species composition and forest dynamics of subalpine coniferousforest ecosystems under future climate change.
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大熊猫(Ailuropoda melanoleuca)是我国特有的珍稀濒危物种,国家Ⅰ级重点保护野生动物,被称为“国宝”。目前,大熊猫被局限在我国中西部的岷山、邛崃、大相岭、小相岭、凉山和秦岭6大山系中。对大熊猫的保护和研究,我国政府、保护生物学科研人员、社会各界及国际保护组织都做了大量的工作。根据全国三次大熊猫调查结果显示,大熊猫栖息地片段化现象依然存在,形成多个隔离的大熊猫小种群。尤其在小相岭、大相岭、岷山B和岷山C种群,大熊猫数量较少,且栖息地破碎,面临较大威胁。有的山系大熊猫种群数量些已低于最小可存活大熊猫种群的数量,如果不采取人工措施,这些种群的大熊猫存在灭绝的危险。 将圈养大熊猫放归野外,以补充野外大熊猫种群数量,增加其遗传多样性,复壮和扩大野生大熊猫种群,是大熊猫人工繁育的最终目标。为降低放归的风险性,在放归人工繁育大熊猫前,将救护存活的野生大熊猫先有计划放归野外,并对其进行跟踪监测,对积累大熊猫放归经验,进一步研究大熊猫野外生物学习性,丰富放归地大熊猫种群遗传多样性,为人工繁育大熊猫放归野外夯实基础,具有十分重要的意义。2005年8月8日,国家林业局和四川省人民政府联合将救护野生大熊猫“盛林1号”放归于龙溪-虹口国家级自然保护区内岷山B大熊猫种群栖息地,并进行系统监测研究。成功的积累了一些放归经验和放归大熊猫的生物学资料,为人工繁育大熊猫的放归奠定了一定基础。 2005年8月至2007年6月期间,我们采用GPS无线电项圈、粪便DNA检测和红外线自动触发相机陷阱的方法,对大熊猫“盛林1号”进行了追踪监测,获得了以下成果: 1.通过分析“盛林1号”放归后了活动趋势和采用两种贝叶斯方法,利用目前五大山系的已有微卫星遗传数据,检测“盛林1号”与五大山系的遗传关系的远近,推测其来源于邛崃山系的可能性较大。 2.收集了大量“盛林1号”野外生境选择数据。我们认为“盛林1号”放归后经历了应急期、初步稳定期、长途迁徙期三个阶段(这可能是今后放归大熊猫都必经的三个时期),并与当地大熊猫种群已发生交流。目前“盛林1号”仍在寻找适合的巢域。 3.结合过去监测数据分析,在放归区域大熊猫和羚牛尽管同域分布,但由于食性不同,对微生境选择还是有着很大差异,因此保护管理对策要有针对性。 4.“盛林1号”的放归是成功的。救护大熊猫异地放归工作应继续开展,但要改进放归后的监测技术。要改进现有对人工饲养大熊猫野化培训方法和放归方式,才能真正将人工繁殖个体放归野外。 Giant Panda (Ailuropoda melanoleuca) is an endangered species endemic to China. It was listed as National Protected I Class Species and is crowned as “National treasure” of China. The populations of Giant Panda are limited in 6 mountain system in Center-West of China, i.e. Mingshan, Mt. Qionglai, Mt. Daxiangling,Mt. Xiaoxiangling, Mt. Liangshan and Mt. Qinling. The results of the Third National Survey on Giant Panda showed that the habitats of Giant Panda is still fracted and Giant Panda population is divided into several isolated small populations. Population B from Mt. Daxiangling, Mt. Xiaoxiangling and Mt. Mingshan and Population C from Mt. Mingshan are very small with very fracted habitat and are more endangered. Several populations in those mountain systems are smaller than Minimum Viable Population of Giant Panda. It is very possible that those populations will be extinct without artificial help. The ultimate Goal of Reintroduction caged Giant Panda to wild is to increase wild population size and genetics diversity and rebuild and expand wild Giant Panda population. It is of significant to return rescued wild Giant Panda to wild and monitor their behavior before reintroduction artificial reproduced Giant Panda. It will increase our knowledge on reintroduction of Giant Panda. Aug 8th, 2005, “Shenglin 1”, a rescued wild Giant Panda was returned to Longxi-Hongkou National Nature Reservoir, which is habitat of Giant Panda Population B of Mt. Mingshan. A systematic monitor was carried out on “Shenglin 1”, and the successful return enriched our biological knowledge on Giant Panda reintroduction. It will be very help for future conservation work on reintroduce artificial reproduced Giant Panda. “Shenglin 1” was tracked with GPS collar, DNA in feces and infrared-trigged camera from Aug 2005 to Jun 2007. 1. Locomotion behavior and microsatellites comparison with Giant Panda from the 5 mountain systems indicated that “Shenglin 1” is possibly from Mt. Qionglai. 2. Habitat usage of “Shenglin 1” was studied. It was suggested that there were 3 phases after return, i.e. emergency response, preliminary stable phase and long distance locomotion, which could be a general process for other returned Giant Panda. It was indicated that there was some interaction between “Shenglin 1” and local population. “Shenglin 1” is seeking for suitable home range now. 3. Monitor data also indicated that microhabitat preference of Giant Panda and takin (Budorcas taxicolor) are different because of different diet, though they are sympatric. It was suggested that conservation management for the two species should be plan in particular. 4. The reintroduction of “Shenglin 1” is a successful case. The program of return rescued Giant Panda to other habitats is of value and should be continued. However, more improvement is needed for the monitor technique. More improvement is need for feralization and returning before we return artificial reproduced Giant Panda to wild.
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<正>在中国科学院近代物理研究所放射性束流装置RIBLL上完成了17Ne+197Au的实验,采用硅条探测器与CsI(Tl)+PIN探测器阵列进行运动学完全测量,研究了17Ne双质子发射的机制。实验选用
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空间辐射环境能够引起半导体集成电路发生的总剂量效应、单粒子效应等辐射效应 ,可以被用来进行空间辐射环境监测。在一定条件下 ,基于此原理的探测器具有常规的面垒型探测器以及 PIN型探测器等所不具备的优点。尤其适合航天器舱内带电离子探测和用于航天医学的个人辐射剂量探测。介绍了三种基于半导体器件辐射效应的探测器。
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An experiment to study exotic two-proton emission from excited levels of the odd-Z nucleus P-28 was performed at the National Laboratory of Heavy Ion Research-Radioactive Ion Beam Line (HIRFL-RIBLL) facility. The projectile P-28 at the energy of 46.5 MeV/u was bombarding a Au-197 target to populate the excited states via Coulomb excitation. Complete-kinematics measurements were realized by the array of silicon strip detectors and the CsI + PIN telescope. Two-proton events were selected and the relativistic-kinematics reconstruction was carried out. The spectrum of relative momentum and opening angle between two protons was deduced from Monte Carlo simulations. Experimental results show that two-proton emission from P-28 excited states less than 17.0 MeV is mainly two-body sequential emission or three-body simultaneous decay in phase space. The present simulations cannot distinguish these two decay modes. No obvious diproton emission was found.
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本文根据反冲质子法中子探头灵敏度标定实验和分层分块模型(LP)理论计算的局限性,提出了一个计算PIN中了探头高灵敏度的方法,即分层分块蒙特卡罗模拟联合模型(LPMC)。文中首先概述了灵敏度标定实验的原理、装置、方法、部分测量结果及其误差。接着分析了分层分块模型的使用范围。最后着重论述了用分层分块蒙特卡罗模拟联合模型计算反冲质子能谱和中子探头灵敏度的方法,并且与分层分块模型计算结果和实验测量结果进行了比较。根据计算过程,用FORTRAN77语言缩写了计算程序LPMC,其计算方法本身的误差不大于1.8%。LPMC计算结果与实验值在相对误差范围内符合,解决了LP理论对高灵敏度计算结果与实验值偏差过大的问题
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在信息产业、生物医学等科技领域越来越受关注的今天,新型光电子、光通信科技必将以更快的速度发展。Si基光电子集成采用成熟价廉的微电子加工工艺,将光学器件与多种功能的微电子电路集成,是实现光通信普及发展和光互连的有效途径。Si基光电探测器是Si基光通信系统的关键器件之一。随着近年来Si基Ge材料外延技术的突破性进展,Si基Ge光电探测器因为兼顾了Si基光电子集成和对光通讯波段(1.31和1.55μm)的高效探测,成为了当今研究的一大热点。
半导体光电探测器的性能与其结构密切相关。PIN型光电探测器是最常见的探测器,可以普遍应用于光通讯光互连系统;雪崩光电二极管(APD)因为具有较高的响应度和内部增益,在实现单光子探测方面具备很大的优越性,适用于当今迅猛发展的生物光子学和量子信息学;共振腔增强型的光电探测器(RCE-PD),集波长选择器、高速光信号接收器于一体,而且具备共振增强作用、高饱和功率输出等特点,是局域网、光纤入户和现代波分复用(Wavelength-Division Multiplexing,WDM)系统光通信网络的一种优选方案;波导结构探测器(Waveguide-PD)可以解除探测器的响应带宽和量子效率之间的矛盾,而且其结构特点更易于实现与调制器等光波导器件的集成,是片上光互连的首选探测器。
本论文围绕高性能Si基Ge光电探测器这一研究目标,开展了多种结构的光电探测器的研制,包括PIN型PD的研制及其优化、吸收区与倍增区分离结构(SACM)的Ge-on-Si APD、RCE-PD和Waveguide-PD,主要研究结果如下:
1. 成功研制了PIN型Ge-on-Si光电探测器,器件在-1V外加偏压下暗电流密度为46.6mA/cm2,在1.31μm和1.55μm波长下器件的量子效率分别为40%和17%;然后改进了实验方法,在制作器件之前将Ge-on-Si材料在850℃条件下快速退火1分钟,从而改善材料质量,器件的暗电流密度降低至4mA/cm2,这是目前国际上报道的最好结果之一。
2. 研制出了PIN型Ge-on-SOI光电探测器,在1.31μm和1.55μm波长的量子效率分别为62%和25%。在-3V外加偏压下,器件的3dB带宽为12.6GHz。25μm直径器件,3dB带宽更是达到了13.4GHz。同时,制作了均匀性很好的1×4探测器阵列,单个器件的3dB带宽达13.3GHz。
3. 在国际上首次研究了硅基锗光电探测器的高饱和特性。在-1V和-2V外加偏压下,探测器的1-dB小信号压缩电流分别为22mA和40mA,相应的光功率分别为67.5mW和110.5mW。
4. 成功研制了吸收区和倍增区分离的Si基Ge雪崩光电二极管,器件的穿通电压Vpt约为29V,击穿电压Vbd(暗电流等于100μA时的电压)为39.5V。在击穿电压附近,如39V时,SACM-Ge-on-Si APD的增益为40。
5. 解决了背面ICP深刻蚀工艺难题,成功制备了中心波长在1.55μm,量子效应高达62%的共振腔增强型Si基Ge光电探测器。
提出一种横向波导型结构Ge-on-SOI光电探测器结构,并对该结构探测器进行了理论计算。
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Dry sliding tests were performed on as-cast magnesium alloys Mg97Zn1Y2 and AZ91 using a pin-on-disc configuration. Coefficients of friction and wear rates were measured within a load range of 20-380 and 20-240 N at a sliding velocity of 0.785 m/s. X-ray differactometer, scanning electron microscopy, tensile testing machine were used to characterize the microstructures and mechanical properties of Mg97Zn1Y2 alloy and AZ91 alloy. Worn surface morphologies of Mg97Zn1Y2 and AZ91 were examined using scanning electron microscopy.
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X-2-y(2)SiO(5):A (A = Eu3+, Tb3+, Ce3+) phosphor films and their patterning were fabricated by a sol-gel process combined with a soft lithography. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), scanning electron microscopy (SEM) optical microscopy and photoluminescence (PL) were used to characterize the resulting films. The results of XRD indicated that the films began to crystallize at 900 degreesC with X-1-Y2SiO5, which transformed completely to X-2-Y2SiO5 at 1250 degreesC. Patterned thin films with different band widths (5 pin spaced by 5 pm and 16 pm spaced by 24 pm) were obtained by a soft lithography technique (micromoulding in capillaries, MIMIC). The SEM and AFM study revealed that the nonpattemed phosphor films were uniform and crack free, and the films mainly consisted of closely packed grains with an average size of 350 run. The doped rare earth ions (A) showed their characteristic emissions in X-2-Y2SiO5 phosphor films, i.e., D-5(0)-F-7(J) (J = 0, 1, 2,3,4) for Eu3+, D-5(3), (4)-F-7(J) (J = 6, 5, 4, 3) for Tb3+ and 5d (D-2)-4f (F-2(2/5),(2/7)) for Ce3+, respectively. The optimum doping concentrations for EU3+, Tb3+ were determined to be 13 and 8 mol% of Y3+ in X-2-Y2SiO5 films, respectively.
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A novel long-lasting phosphor CdSiO3:Mn2+ is reported in this paper. The Mn2+-doped CdSiO3 phosphor emits orange light with CIE chromaticity coordinates x = 0.5814 and y = 0.4139 under 254 nm UV light excitation. In the emission spectrum of 1% Mn2+-doped CdSiO3 phosphor, there is a broad emission band centered at 575 nm which can be attributed to the,pin-forbidden transition of the d-orbital electron associated with the Mn2+ ion. The phosphorescence can be seen by the naked eyes in the dark clearly even after the 254 nm UV irradiation have been removed for about 1 h. The mechanism of the origin of the long-lasting phosphorescence was discussed using the thermoluminescence curves.
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Zhikong scallop Chlamys farreri(Jones et Preston) is an economically important species in China. Understanding its immune system would be of great help in controlling diseases. In the present study, an important immunity-related gene, the Lipopolysaccharide and Beta-1,3-glucan Binding Protein (LGBP) gene, was located on C. farreri chromosomes by mapping several lgbp-containing BAC clones through fluorescence in situ hybridization (FISH). Through the localization of various BAC clones, it was shown that only one locus of this gene existed in the genome of C. farreri, and that this was located on the long arm of a pair of homologous chromosomes. Molecular markers, consisting of eight single nucleotide polymorphism (SNPs) markers and one insertion-deletion (indel), were developed from the LGBP gene. Indel marker testing in an F1 family revealed slightly distorted segregation (p = 0.0472). These markers can be used to map the LGBP gene to the linkage map and assign the linkage group to the corresponding chromosome. Segregation distortion of the indel marker indicated genes with deleterious alleles might exist in the surrounding region of the LGBP gene.
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Large-insert bacterial artificial chromosome (BAC) libraries are necessary for advanced genetics and genomics research. To facilitate gene cloning and characterization, genome analysis, and physical mapping of scallop, two BAC libraries were constructed from nuclear DNA of Zhikong scallop, Chlamys farreri Jones et Preston. The libraries were constructed in the BamHI and MboI sites of the vector pECBAC1, respectively. The BamHI library consists of 73,728 clones, and approximately 99% of the clones contain scallop nuclear DNA inserts with an average size of 110 kb, covering 8.0x haploid genome equivalents. Similarly, the MboI library consists of 7680 clones, with an average insert of 145 kb and no insert-empty clones, thus providing a genome coverage of 1.1x. The combined libraries collectively contain a total of 81,408 BAC clones arrayed in 212 384-well microtiter plates, representing 9.1x haploid genome equivalents and having a probability of greater than 99% of discovering at least one positive clone with a single-copy sequence. High-density clone filters prepared from a subset of the two libraries were screened with nine pairs of Overgos designed from the cDNA or DNA sequences of six genes involved in the innate immune system of mollusks. Positive clones were identified for every gene, with an average of 5.3 BAC clones per gene probe. These results suggest that the two scallop BAC libraries provide useful tools for gene cloning, genome physical mapping, and large-scale sequencing in the species.
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Six species belonging to two families of Hemichordata have previously been recorded in Chinese waters. This paper records the discovery and description of a new species of the genus Glandiceps found in Jiaozhou Bay, Qingdao, Shandong Province, named Glandiceps qingdaoensis. The new species has a long proboscis with dorsal and ventral grooves, a stomochord with a long vermiform process, a proboscis cavity with a dorsal median, right and left glomeruli, right and left glomeruli very large and encircling the stomochord, a proboscis skeleton in the cavity extends into the median posterior of the collar, a well-developed dorsal ventral muscular septum in the proboscis cavity dividing the cavity completely into two separate parts. The collar cord is without giant nerve roots. The trunk with four distinct regions that can be recognized externally: branchial-genital region, genital region, hepatic region, and intestinal region. The dorsal pharynx is large and the gill pores are small. The tongue bars are encircled by vesicles, and the first gonad commences at the level of the second or third gill slit.
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Two new urostylid ciliates, Metaurostylopsis songi n. sp. and Metaurostylopsis salina n. sp. and Metaurostylopsis marina (Kahl 1932) are investigated using live observation and protargol impregnation. These species were isolated in Korea from intertidal sediments, saline ponds, and coastal waters. Metaurostylopsis songi is in vivo about 120 pm x 25 mu m, has a slenderly ellipsoidal body, colorless cortical granules in rows on ventral and dorsal body sides, about 54 macronuclear nodules, 28-47 adoral membranelles, five frontal, two or three frontoterminal and six or seven transverse cirri, and 9-12 midventral cirral pairs followed posteriorly by 1-3 single cirri. In vivo M. salina is about 60 pin x 25 mu m, has a pyriform body, colorless cortical granules irregularly arranged, about 45 macronuclear nodules, 18-23 adoral membranelles, three frontal, three to five frontoterminal and two to five transverse cirri, and four or five midventral cirral pairs followed posteriorly by five to seven single cirri. Both species have three marginal cirral rows on each body side and 3 long dorsal kineties. The Korean specimens of M. marina match the Chinese population in all main features. Metaurostylopsis songi differs from M. marina by the more slender body, the number of frontal cirri (invariably five vs. four), and the arrangement of cortical granules (in rows on dorsal and ventral cortex vs. only along dorsal kinetics and anterior body margin). Metaurostylopsis salina differs from its congeners by the distinctly smaller size, the pyriform body shape, the scattered cortical granules (vs. in rows), and number of frontal cirri. It differs from M. marina also by the number of midventral cirral pairs (four or five vs. seven to 11).