氮肥和水分条件对长喙田菁生长、结瘤和固氮的影响

 盆栽试验研究了长喙田菁(Sesbania rostrata) 茎瘤固氮根瘤菌（Azorhizobium caulinodans）共生体系在不同水分和无机氮肥条件下的生长、结瘤和氮积累。水分处理为: 不浸水、浅浸水(土壤水分为田间持水量)和深浸水, 氮肥处理分别为每千克土施加无机氮肥10 mg、20 mg和40 mg。结果表明,水分条件对共生体系有较大影响, 浸水环境虽然抑制了根瘤的形成, 却促进了茎瘤的结瘤作用和长喙田菁根系的生长, 田间持水量状态下共生体系能获得最大的生物量和氮累积量; 无机氮肥对共生体系的影响受水分供应的影响较大,实验氮肥施用浓度范围内,长喙田菁的结瘤作用对复合态氮无负敏感反应,明显有别于一般根瘤体系的复合态氮反应。     

茎瘤对长喙田菁在铅锌尾矿环境适应中的意义II 茎瘤对长喙田菁固氮和积累重金属的影响

探讨茎瘤对长喙田菁(Sesbania rostrata)在铅锌矿尾矿、客土和纯土环境中结瘤、固氮和积累重金属的影响。结果表明：保留茎瘤使长喙田菁全株植物氮含量和单株植物氮积累量分别比去除茎瘤处理提高了12.4%～34.0%和43.3%～131.4%,且环境愈恶劣,这种作用愈为显著。同时,保留茎瘤处理显著抑制了长喙田菁根瘤的生长,同样表现出环境愈恶劣,抑制作用愈显著的趋势。因此,在尾矿环境胁迫下,长喙田菁更趋向于选择茎瘤作为固氮途径。由此可见,茎瘤对生长在铅锌尾矿环境中的长喙田菁获得氮素及支持其生长有着特别     

茎瘤对长喙田菁在铅锌尾矿环境适应中的意义II 茎瘤对长喙田菁固氮和积累重金属的影响

 探讨茎瘤对长喙田菁(Sesbania rostrata)在铅锌矿尾矿、客土和纯土环境中结瘤、固氮和积累重金属的影响。结果表明：保留茎瘤使长喙田菁全株植物氮含量和单株植物氮积累量分别比去除茎瘤处理提高了12.4%～34.0%和43.3%～131.4%,且环境愈恶劣,这种作用愈为显著。同时,保留茎瘤处理显著抑制了长喙田菁根瘤的生长,同样表现出环境愈恶劣,抑制作用愈显著的趋势。因此,在尾矿环境胁迫下,长喙田菁更趋向于选择茎瘤作为固氮途径。由此可见,茎瘤对生长在铅锌尾矿环境中的长喙田菁获得氮素及支持其生长有着特别     

生态条件对马占相思结瘤固氮的影响

本文研究了马占相思（Ａｃａｃｉａｍａｎｇｉｕｍ）结瘤固氮和生态条件的关系．结果显示．马占相思根瘤固氮活性的昼夜变化与固氮能源的供给有关,它受光、温影响较大,固氮活性昼夜变化的范围为１—５μｍｏｌＣ２Ｈ４·ｇ－１ｆｒｅｓｈｎｏｄｕｌｅｈ－１。固氮活性的季节性差异也很明显,且与温、湿度的变化关系密切,在温、湿度较好的５月—１０月．固氮活性较高．为３—１０μｍｏｌＣ２Ｈ４·ｇ－１ｆｒｅｓｈｎｏｄｕｌｅｈ－１．冬春的干旱和低温会影响根瘤的生长和存活．造成固氮活性降低甚至失去活性．不同年份和林地的根瘤生物量为１０４—６２５ｋｇ·ｈａ－１,以幼林期根瘤生物量较高．多数样地的根瘤生物量在３００ｈｇ·ｈａ－１以上．随着森林生态系统的发展．根系往土层深处生长以及林下草本和灌木层的增长等原因,根瘤生物量会受影响而有所下降。施肥松土能提高根瘤生物量５７—３４４ｋｇ·ｈａ－１,对增加固氮量有重大意义。     

毛萼田菁茎瘤菌（Azorhizobium caulinodans）吸氢活性缺陷株的筛…

利用转座子Ｔｎ５随机插入突变法,从毛萼田菁茎瘤菌中筛选得到两株吸氢活性缺陷突变株Ｒ－４９和Ｒ－３０９,其固氮酶活性也大大降低,约为野生型固氮酶活性的６－８％。以带有Ｂｒａｄｙｒｈｉｚｏｂｉｕｍ ｊａｐｏｎｉｃｕｍ的５．９ｋｂ的ｈｕｐ基因的质粒ＰＨＲ１１为探针与Ａ．ｃｏｕｌｉｎｏｄａｍｓＯＲＳ５７１和Ｂ．ｊａｐｏｎｉｃｕｍ１２２ＤＥＳ（Ｈｕｐ）的总ＤＮＡ进行分子杂交,放射自显影表明,Ａ．ｃｏｕｌｉｎ     

营养杯对长喙田菁在铅锌尾矿上的生长、固氮和重金属积累的影响

设置移栽时营养杯的有无及其大小作试验,研究长喙田菁在乐昌铅锌矿强酸化尾矿上的生长、固氮和积累重金属情况。结果表明,强酸性(pH<3)是限制植物定植的主要因素,在pH=5-7情况下,长喙田菁能在该尾矿库中定植、生长和固氮,表现出良好的适应性。未带营养杯移栽的长喙田菁在尾矿上生长84d,其株高117cm、茎基部直径1.35cm、单株生物量(干物质)20.2g、单位面积生物量(干物质)2828kghm-2、氮素积累量40kghm-2;带营养杯移栽的上述各指标分别达到140-144cm、1.59-1.68cm、36.6-38.8g、5124-5432kghm-2和77-107kghm-2,均显著高于未带营养杯处理的。长喙田菁根部铅、锌、铜、镉含量均最高,其次为茎,叶中最低;长喙田菁的4种重金属积累量为锌(186-221mgkg-1)>铅(96-145mgkg-1)>铜(17-30mgkg-1)>镉(3-4mgkg-1)。带营养杯移栽能有效提高长喙田菁的产量和氮积累量,且明显降低其体内的重金属含量。试验证明长喙田菁是较理想的铅锌矿尾矿废弃地植被重建的先锋植物。     

河西走廊豆科植物结瘤固氮特性初步研究

对甘肃河西走产野生豆科植物结瘤及固氮状况进行了调查。栽培豆科植物均能自然结瘤,野生豆科植物结瘤率仅５０％。该地区豆科植物根瘤大多数圆形、棒状或指状,形状较为规则。栽培植物根瘤多为粉红色,而野生揿为白色、黄色或棕色。ＡＲＡ测定表明,２５．６％根瘤为无效根瘤。不同种不同地区根瘤固氮活性相差较大,一般活力都较低,乙炔还原活性小１μｍｏｌＣ２Ｈ４／ｇＦＷ．ｈ的占检测样品数的２９．９％,最高者信为２８．１９     

茎瘤固氮根瘤菌（Azorhizobium caulinodans）ORS 571产生的植物激素

茎瘤固氮根瘤菌（Ａｚｏｒｈｉｚｏｂｉｕｍｃａｕｌｉｎｏｄａｎｓ）ＯＲＳ５７１菌株在离体培养条件下,能利用色氨酸合成吲哚乙酸（ＩＡＡ）。随着菌龄的老化,合成的ＩＡＡ量也增加。除ＩＡＡ外,该菌株还产生类ＧＡ物质。本研究未检出细胞分裂素（Ｃｙｔｏｋｉｎｉｎ）类物质。     

果胶菌加根瘤菌诱发油菜结瘤固氮研究新进展

果胶细菌（ｐｅｃｔｉｎ－ｌｙｔｉｃ ｂａｃｔｅｒｉａ）处理油菜幼根（二天苗龄,根长３ｃｍ）,同时接种紫云英根瘤菌突变菌株（Ｒｈｉｚｏｂｉｕｒｎ ｓｐｐ．ａｓｔｒａｇｌｕｓ）结瘤率为９６．８０％。根瘤石蜡包理切片观察,结果是从根瘤的外皮层到内皮层细胞均有细菌的分布。乙炔还原法测定出低固氮酶活性（７３．１０ｎｂ ＭＣ２Ｈ４／株／小时）。在植株全氮、干重和盆栽产量上都有不同程度的增加。     

北方稻田生态系统研究Ⅱ．稻萍结合系统细绿萍共生固N量研究

对稻萍结合系统细绿萍共生固Ｎ量研究表明,萍的固Ｎ力在整个生长季不同时期有所变化．最高固Ｎ率出现在６月初,萍固Ｎ量随其接种量和水稻行距增加而增加．５０～１０ｃｍ宽窄行交替的水稻行距和１５００ｋｇ·ｈｍ－２的萍接种量的稻萍结合系统的总固Ｎ量为１０７．１ｋｇ·ｈｍ－２,而３０ｃｍ等行距的３２５ｋｇ·ｈｍ－２的萍接种量的稻－萍结合系统的总固Ｎ量仅为３６．０ｋｇ·ｈｍ－２     

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.     

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.     

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.     

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.