钙质红藻化石的主要类群特征及演化

钙质红藻是指可以发生生物钙化作用在其细胞壁上沉淀碳酸钙的红藻。钙质红藻可以保存为化石,是红藻古生物研究中的重要类群,具有重要的生态意义,但以往的研究对钙质红藻类群的系统分类及地史分布缺乏清晰认识。本文详细综述了钙质红藻化石的系统分类,归属于红藻门(Rhodophyta)红藻纲(Rhodophyceae)的4个目7个科,分别为珊瑚藻亚纲(Corallinophycidae)珊瑚藻目(Corallinales)的珊瑚藻科(Corallinaceae)、石叶藻科(Lithophyllaceae)、宽珊藻科(Mastophoraceae)和管孔藻科(Solenoporaceae),混石藻目(Hapalidiales)的混石藻科(Hapalidiaceae),孢石藻目(Sporolithales)的孢石藻科(Sporolithaceae)以及真红藻亚纲(Florideophycidae)耳壳藻目(Peyssonneliales)的耳壳藻科(Peyssonneliaceae)。最早的钙质红藻为管孔藻科,出现于中奥陶世,于中新世灭绝。珊瑚藻科最早出现于晚志留世并于白垩纪辐射演化至今,其他科均于白垩纪...     

河北张家口下花园青白口系下马岭组"红藻石"的发现

红藻石由红藻形成。绝大部分红藻石与珊瑚藻有关。珊瑚藻形成的红藻石发育于中新生代,早古生代有管孔藻形成的红藻石。本文记录了发现于下花园地区的新元古代青白口系下马岭组四段的红藻石。这类红藻石的中心部分被沥青充填。通过薄片观察发现沥青饼的周围硅化部分存在两类红藻四分孢子囊：一类四分孢子囊包埋于球状构造内,另一类四分孢子囊包埋于叶片状构造内。     

昆明海口早寒武世澄江生物群中叶状红藻化石

主要报道了采自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.).通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据.同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30 m以上的亚潮带和下潮间带的海水环境.     

昆明海口早寒武世澄江生物群中叶状红藻化石

主要报道了釆自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.)。通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据。同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30m以上的亚潮带和下潮间带的海水环境。     

几种绿藻、褐藻和红藻的吸收光谱的比较研究

1.用乳白玻璃法测定了我国黄海常见的属于绿藻门、褐藻门和红藻门的十种海藻的吸收光谱。讨论了这三门海藻的吸收光谱的特点。通过对吸收光谱及红藻、褐藻相对于绿藻的差异光谱的分析,讨论了各种色素在活体中的吸收峰和吸收带的位置。2.根据褐藻与绿藻的吸收光谱的差异及差异光谱的比较分析,认为绿藻吸收光谱中位于485(或480)毫微米的吸收峰是叶绿素 b 的蓝光吸收峰。叶绿素 b 的红光吸收峰位于655毫微米附近。岩藻黄素的吸收峰位于525毫微米附近。根据红藻吸收光谱及其同绿藻的差异光谱中的红光吸收峰和负峰的特点,初步认为红藻中的叶绿素 d 的红光吸收峰比叶绿素 a 的红光吸收峰位于较长波长处。3.对几种红藻的吸收光谱进行了比较。观察到原始红藻纲的条斑紫菜(Porphyra yezoen-sis)的藻胆素与真红藻纲的藻类有显著的差异。这种差异及条斑紫菜的藻胆素的含量和组成上的易变性值得进一步研究。     

塔里木盆地早寒武世灰泥丘孔洞中钙化红藻生殖器官化石的发现

2002年10月,作者对塔里木盆地柯坪肖尔布拉克剖面下寒武统肖尔布拉克组碳酸盐岩进行了野外考察,之后进行了较为详细的室内薄片鉴定和岩石学、沉积学及古生物学研究,发现肖尔布拉克组碳酸盐岩为典型的灰泥丘建造。而且,在灰泥丘的孔洞方解石薄片中,发现这些孔洞是球状钙化红藻生殖器官化石,该球状红藻生殖器官具有托叶保护,托叶内发育囊果包被,囊果内发育有孢子囊群。将此化石命名为Calciumcarpium xiaolbu-lakeurn gen. et sp. nov. o?A这一发现和认识,丰富了寒武纪藻类生物群的内容,明确了肖尔布拉克组灰泥丘中孔洞与红藻生殖器官之间的联系,在沉积学、古生物学研究上具有一定意义。     

河北张家口下花园地区新元古代下马岭组油页岩中的红藻化石

通过对下花园地区晚前寒武纪下马岭组油页岩的研究,发现了保存极为完好的红藻化石,同时也发现特定的底栖宏观红藻可以作为重要生烃母质,在中—低成熟度条件下,甚至可以成为重要生油母质。     

走进淡水中的红藻

正红藻是起源最为古老的真核生物类群之一,具有复杂漫长的演化历史。大多数红藻生长在海洋中,是海洋中重要的光合生物。淡水中的红藻种类不多,仅有200多种。由于它们对生境的要求较高,只在清冷洁净的水体中才能生长,我们一般只能在一些泉水溪流中才能看到它们的身影。同时随着社会工业化和旅游业的快速发展、水环境污染的加剧,一些淡水红藻种类已成为濒危物种。     

癫痫发作敏感大鼠前深梨状皮层T区GABA免疫反应活性变化

γ-氨基丁酸(γ-aminobutyric acid,GABA)是脑内最重要的抑制性神经递质,在阻断兴奋扩布及传导中起重要作用,其参与抗癫痫作用已被证实.有研究表明:前深梨状皮层T区是颞叶癫痫的始动部位.我们从前的工作已证明:惊厥剂量的红藻氨酸(Kainic acid,A)诱发SD大鼠出现急性癫痫发作后的5～7 d,动物出现癫痫发作敏感性长期增强,而蝎毒(scorpion venom,V)可通过增强海马结构内GABA的表达,对抗其癫痫发作敏感性的形成.本研究采用免疫组化技术,并探讨其与癫痫发作敏感长期增强的可能关系,检测癫痫发作敏感大鼠和经SV处理后癫痫发作敏感性明显降低的大鼠前深梨状皮层T区的GABA免疫反应活性变化.     

长白山北坡垂直植被带木本植物的植硅体形态特征及其环境意义

长白山垂直分布的植被是温带到寒带植被的组合,能够很好地反映温度变化趋势,研究其植物的植硅体对于了解长白山气候变迁有重要意义.作者选择长白山9科14属木本植物的叶子,采用湿式灰化法对其进行植硅体分析,计算了不同形态植硅体的百分含量,同时测量了长度和宽度.研究表明:长白山北坡垂直植被带中典型木本植物的叶子具有8种植硅体类型:表面有突起、皱纹的椭圆形、卵形;具有螺旋纹的纺锤状以及导管形、弓形、鸟嘴状、扁棒型、石块状、松树皮状、不确定型.在14种木本植物叶子中都出现了扁棒型植硅体,其含量随海拔升高逐渐增加,说明在长白山区扁棒型植硅体是示冷型植硅体.阔叶类木本植物叶子中,具有螺旋纹的纺锤体及导管形、弓形植硅体占优势;裸子植物叶子中松树皮状、石块状植硅体,其含量随海拔升高逐渐递减,说明松树皮状和石块状植硅体是示暖型植硅体.     

Simultaneous measurement of the trace elements Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum and their reference ranges by ICP-MS

The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.     

Distribution of N,P, K,Ca, Mg,S, Zn,Fe, Mn and Cu in groundnut

Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.     

Crystal structure, detonation performance, and thermal stability of a new polynitro cage compound: 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptacyclo [5.5.1.13, 11. 15, 9] pentadecane

A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.     

Reference values for the concentrations of As,Cd, Co,Cr, Cu,Fe, I,Hg, Mn,Mo, Ni,Pb, Se,and Zn in selected human tissues and body fluids

This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.     

Relations of the Al,B, Ba,Br, Ca,Cl, Cu,Fe, K,Li, Mg,Mn, Na,P, S,Si, Sr,and Zn mass fractions to morphometric parameters in pediatric and nonhyperplastic young adult prostate glands

The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.     

Monovalent Cation Permeation through the Connexin40 Gap Junction Channel : Cs,Rb, K,Na, Li,TEA, TMA,TBA, and Effects of Anions Br,Cl, F,Acetate, Aspartate,Glutamate, and NO3

The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γ_j in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γ_j are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO₃ (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li⁺ are: Cs⁺ (1.38), Rb⁺ (1.32), K⁺ (1.31), Na⁺ (1.16), TMA⁺ (0.53), TEA⁺ (0.45), TBA⁺ (0.03), Cl⁻ (0.19), glutamate⁻ (0.04), and NO₃− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.     

The Effect of Age and Gender on Al, B, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Na, P, S, Sr, V, and Zn Contents in Rib Bone of Healthy Humans

The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.     

Caprine blood groups. 2. The C,G, H,I, J,K, L,N, and Q systems

Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera. The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents and shown to be controlled by three alleles,C ¹²,C ²⁵, andC ⁻. A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled by six codominant alleles (G ^10.19.20,G ^10.19,G ^10.20,G ¹⁰,G ¹⁹,G ²⁰) and a recessive allele (G ⁻). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively. This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia.