中国翼手目六个类群的比较分子细胞遗传学研究

翼手类(Order Chiroptera)是哺乳动物中最为神秘的类群之一。它们也是哺乳动物中唯一真正具有空中飞翔能力的动物，而且多数物种还具有回声定位功能。翼手目分布十分广泛，除南极洲之外全球几乎任何地方都有分布，其数量约占整个哺乳动物种类的20％。然而，有关该类群的许多系统发育假说仍存有争议，至今其进化历史还不是很清楚，并且形态和分子研究所得出的结论经常不一致。近年来分子细胞遗传学的发展,特别是比较染色体涂色及其相关技术的应用，使人们可以快速、准确地鉴定种间的同源染色体（或同源染色体片段）。根据构建的染色体同源图谱及外群比较可确定一些细胞遗传学特征，并将其用于系统发育研究。虽然比较染色体涂色技术已广泛应用在哺乳动物的核型进化和系统发育研究中，但是在翼手目中却相当滞后。到目前为止，仅有少数蝙蝠物种有染色体涂色数据。 本研究分别利用三叶小蹄蝠（蹄蝠科）、大鼠耳蝠（蝙蝠科）及人的染色体特异性涂色探针，通过种间染色体涂色，首次比较系统的构建了狐蝠科（3种）、菊头蝠科（6种）、蹄蝠科（4种）、假吸血蝠科（1种）、鞘尾蝠科（1种）和犬吻蝠科（2种）共6个科17种蝙蝠间的染色体同源图谱，并将它们与已发表的染色体图谱进行整合。我们的结果不仅揭示了这些物种间的核型进化关系及其核型进化的主要机制，而且加深了我们对整个翼手目系统发育关系的认识。研究结果表明： 1） 长舌果蝠亚科和狐蝠亚科的果蝠部分物种的核型（2n = 36）可能代表了整个狐蝠科的祖先形式，而狐蝠亚科的犬蝠部分物种的核型属于衍生形式。2） 整臂保守性广泛存在于菊头蝠属物种的核型进化中，罗伯逊易位是其核型进化的主要方式。此外，整臂的相互易位也可能在其中起一定的作用。 3） 蹄蝠科核型进化的主要机制为罗伯逊易位和臂内倒位。而臂内倒位和异染色质扩增在蹄蝠属的物种形成中可能起了非常重要的作用。 4） 与蹄蝠属相比，三叶蹄蝠属物种的核型中可能包含更多的祖先染色体或染色体片段；中蹄蝠与大蹄蝠具有较近的亲缘关系；与中蹄蝠和大蹄蝠相比，小蹄蝠的核型较为原始。 5） 犬吻蝠科内来自不同属但具有相同二倍染色体数目的物种间核型非常保守；该科物种核型间的差异主要是由倒位和异染色质的分布引起的。 6） 菊头蝠超科的菊头蝠科、蹄蝠科和假吸血蝠科具有较近的亲缘关系，并且它们与大蝙蝠亚目的狐蝠科共有一些细胞遗传学特征，进一步支持了小蝙蝠亚目双系起源的观点。

Ferrimagnetic and semiconducting CaCu3Fe2Sb2O12 by first principles

CaCu3Fe2Sb2O12 is mechanically stable, thermodynamically stable at pressures above 18 GPa. Both GGA and GGA + U methods predict that it is a ferrimagnetic semiconductor with Fe3+ in high spin state (S = 5/2). The coupling of Fe-Cu is antiferromagnetic, while that of Cu-Cu is ferromagnetic. The calculated total spin moment is 6.17 mu(B).

重力对聚合物形成的影响

在聚合物合成过程和聚合物凝固过程中，聚合物分子量和聚合物颗粒尺寸的大小、分布和聚合物聚集态结构强烈依赖于重力。文中分增重力、减重力和微重力3 部分阐述了近年来重力对聚合物形成影响研究概况，重点介绍了微重力下聚合物的一些研究成果，并指出了今后的发展方向。

应用量化参数和拓扑指数研究吡喃酮类化合物结构与活性的相关性

将量子化学参数和拓扑指数共同应用于吡喃酮类化合物的结构与活性的相关分析中,并运用逐步回归分析方法和最佳变量子集算法对变量进行压缩,通过多元回归方法和人工神经网法进行计算分析,获得了比较好的相关模型.

耐盐抗温水溶性聚合物AM-NaAMPS-DEAM的合成及性能研究

以丙烯酰胺（AM），2－丙烯酰胺－2－甲基丙碳酸钠（NaAMPS），N，N－二乙基丙烯酰胺（DEAM）为单体，通过在水溶液中自由基引发共聚合，合成出了AM－NaAMPS－DEAM三元共聚物。并对该三元共聚物的聚合物工艺条件，及对产物性能的影响进行了研究。初步考察了该共聚物的耐盐抗温性能。结果表明：采用本工艺可以制备出分子量大于1200万，增粘效果明显，耐盐抗温性能显著优于HPAM的三元共聚物。

辐照聚乙烯的熔融和重结晶

用差示扫描量热法（ＤＳＣ），小角Ｘ－射线散射（ＳＡＸＳ），广角Ｘ－射线衍射（ＷＡＸＤ）等考察了辐照聚乙烯的熔融和重结晶。辐照破坏了聚乙烯结晶结构，使其熔融温度、结晶度均随辐照剂量的增加而降低。将辐照聚乙烯熔融再结晶，其重结晶度、熔融温度随辐照剂量而下降的幅度较大。其原因被归结为片晶劈裂。

电子能谱法研究改性的聚丙烯纤维性能与结构关系

本文讨论了聚丙烯纤维（PPF）在Ar、N2、O2和空气等离子体作用时，改变时间和功率对PPF表面进行等离子体处理，发现处理后纤维的吸湿性变化很大，回潮率是未处理样品的120-400%，染色性能从5级提高到1级标准。这一变化的光电子能谱法研究结果表时：PPF表面的结构发生较大变化。表面大量引入含O、N极性基团。经谱图拟合可知，这些基团是亲水性的极性结构，应归属于C-OH、C=O、COOH、C-NH2和CONH2基团。

在镍系钙钛矿(ABO_3)型催化剂上的氨氧化 Ⅲ.焙烧温度对催化剂结构和活性的影响

本文探讨了焙烧温度对催化剂结构及氨氧化活性的影响。得出:La_(0.9)Sr_(0.1)NiO_(3-λ)在1223K后分解,生成具有K_2NiF_4结构的La_2NiO_4相,NiO相和LaNiO_3相。催化活性相主要是具有钙钛矿结构的组分。最佳活性相在1273K形成。

水系背景值调查中锌污染的研究

在水系背景值调查中,出现了溶解态锌(经0.45μ微孔滤膜过滤后过滤水中的锌量)超过总量锌(未经过滤的原水中的锌量)的倒置现象。为了寻找产生倒置的原因,本文从使用的分析方法、容器、滤膜、导水管和环境等各个方面,研究了锌分析结果不正常的原因。最后证实,过滤时用的导水管材料不当,和过滤时的环境是污染的主要原因。

Eu~(2+)和Ce~(3+)激活的BaYF_5荧光性质

本文讨论了BaYF_5中Eu~(2+)和Ce~(3+)的光谱特征及浓度对光谱的影响。Eu~(2+)和Ce~(3+)均表现为d—f跃迁的特征激发和发射。由于Eu~(2+)—Eu~(2+),Ce~(3+)—Ce~(3+)能量迁移的存在,两者猝灭浓度偏低,其猝灭机理为偶极-偶极相互作用。根据BaYF_5基质中Eu~(2+)和Ce~(3+)的能级关系,发现Ce~(3+)对Eu~(2+)的发射具有明显的敏化作用。其机理主要为非辐射多极子作用,但也存在辐射传递。

A review of advances in research on marine molluscan antimicrobial peptides and their potential application in aquaculture

Antimicrobial peptides (AMPs) are important components of the host innate immune response against microbial invasion. They are usually characterized by their small-size, heat-stability and broad range of antimicrobial activity. This review covers research advances on marine mollusc AMPs, specifically those isolated from mussels, scallops, oysters, venerid clams and abalone, which mainly include MGD, mytilin, myticin, mytimycin, big defensin, and RPD-1. Their structural characteristics, antibacterial activity, and expression pattern as well as peptide distribution and their release following microbial challenge are also discussed. In addition, the prospect of the application of AMPs as food additives or their use in immunostimulation to prevent diseases of aquatic animals, as well as their potential hazards, are also discussed.

Formation of Fe-oxyhydroxides from the East Pacific Rise near latitude 13 degrees N: Evidence from mineralogical and geochemical data

The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.

Interactions between the bloom-forming dinoflagellates Prorocentrum donghaiense and Alexandrium tamarense in laboratory cultures

Interactions between Prorocentrum donghaiense and Alexandrium tamarens, two bloom-forming dinoflagellates, were investigated using bi-algal cultures. All R donghaiense died, but A. tamarense was hardly affected by the end of the experiment when the initial cell density was set at 1.0 X 10(4) cells mL(-1) for P. donghaiense and 0.28 x 10(4) cells mL(-1) for A. tamarense. However, significant growth suppression occurred in either species when the initial cell density of P donghaiense increased to I. 0 X 105 Cells mL(-1) in the bi-algal culture, but no out-competement was observed. The simultaneous assay on the culture filtrates showed that P donghaiense filtrate prepared at a lower initial density (1.0 X 10(4) cells mL(-1)) stimulated growth of the co-cultured A. tanzarense (0.28 x 10(4) cells mL(-1)), but filtrate at a higher initial density (1.0 x 10(5) cells mL(-1)) depressed its growth. The filtrate of A. tamarense at a density of 0.28 x 10(4) cells mL(-1) killed all R donghaiense at a lower density (1.0 x 10(4) cells mL(-1)), but only exhibited an inhibitory effect on it at a higher density (1.0 x 10(5) cells mL(-1)). It is likely that these two species of microalgae interfere with each other mainly by releasing allelochemical substance(s) into the culture medium, and a direct cell-to-cell contact was not necessary for their mutual interaction. The allelopathic test further proved that A. tamarense could affect the growth of co-cultured P. donghaiense by producing allelochemical(s); moreover, A. tamarense culture filtrate at the stationary growth phase (SP) had a strongly inhibitory effect on P donghaiense compared to that at the exponential phase (EP). Results also demonstrated a dose-dependent relationship between the microalgal initial cell density and the degree of the allelopathic effect. The growth of R donghaiense and A. tamarense in the bi-algal cultures was simulated using a mathematical model to quantify the interaction. The estimated parameters from the model showed that the inhibition exerted by A. tamarense on P. donghaiense was about 17 and 8 times stronger than the inhibition P. donghaiense exerted on A. tamarense, when the initial cell density was set at 1.0 X 10(4) and 1.0 X 10(5) cells mL(-1) for P donghaiense, respectively. and 0.28 x 10(4) cells mL(-1) for A. tamarense in the bi-algal cultures. A. tamarense seems to have a survival strategy that is superior to that of P. donghaiense in bi-algal cultures under controlled laboratory conditions. (c) 2006 Elsevier B.V. All rights reserved.