Calculation of chemical bond parameters in La1-xCaxCrO3 (0.0 <= x <= 0.3)

The chemical bond parameters, that is, bond covalency, bond susceptibility, and macroscopic linear susceptibility of La1-xCaxCrO3 (x = 0.0, 0.1, 0.2, 0.3) has been calculated using a semiempirical method. This method is the generalization of the dielectric description theory proposed by Phillips, Van Vechten, Levine, and Tanaka (PVLT). In the calculation of bond valence, two schemes were adopted. One is the bond valence sums (BVS) scheme, and the other is the equal-valence scheme. Both schemes suggest that for the title compounds bond covalency and bond susceptibility are mainly influenced by bond valence and are insensitive to the Ca doping level or structural change. Larger bond valences usually result in higher bond covalency and bond susceptibility. The macroscopic linear susceptibility increases (only slightly for BVS scheme) with the increasing Ca doping level. (C) 1999 John Wiley & Sons, Inc.

大洋有孔虫微量元素研究

The most novel aspect of this thesis is the combination analysis of the boron isotopes and trace elements. What’s more, it also provides a reliable analytical technique, which is suitable for both boron isotopes and trace elements. Al/Ca values can be used to monitor the clay removal during the sample preparation. It is found that when Al/Ca>100 mol/mol, the measured boron isotopic compositions are always several permil lower than those properly cleaned. B/Ca ratios can be used to calculate the exact boron loaded for each sample. Otherwise, too much loading will lead to too long time for the whole analytical sequence, and too less loading might incur serious blank problem. One other benefit besides those discussed above is that the combination analysis of boron isotopes and trace elements on the same sample allows reconstruction of the marine carbonate system and atmospheric pCO2 without assumption of the other parameter. In the marine carbonate system, with the seawater pH from the foraminiferal 11B, one has to make an assumption on the other variable to obtain the rest four variables. A series studies found that U/Ca and B/Ca are potential proxies for seawater [CO32-]and [HCO3-], respectively. Since they are measured on the same sample with boron isotopes, hence, there is no spatial or temporal ambiguity in the incorporation of the two controlling parameters. With 11B and U/Ca, the reconstructed atmospheric pCO2 variations match the atmospheric pCO2 record from the Vostok ice core within ±20 ppm. The incorporations of U and B into foraminiferal carbonates are controlled by the overall growth rate of individual foraminifers and other possible factors. The reliable application of these proxies still require further calibrations. In a similar fashion, the combination analysis of boron isotopes and Mg/Ca also has great advantages. Mg/Ca has been proved to be a reliable proxy for the surface seawater temperature. With the combination analysis, one can determine the phase between changes in atmospheric pCO2 and surface seawater temperature, thus explore the cause and mechanism of the changes in atmospheric pCO2. .

岩石圈伸展对粤北下庄矿田铀成矿的制约机制研究

地球动力学与成矿关系的研究是地球科学研究的前沿领域，而陆内岩石圈伸展与成矿的关系的研究则是该领域相对比较薄弱的环节。 华南地区于白垩—古近纪发生了岩石圈强烈的伸展减薄事件，且岩石圈伸展减薄与该区同时期形成的众多金属和非金属矿床有密切的成因联系，尤其是华南地区的花岗岩型热液铀矿床，显示了与该区岩石圈伸展作用可能有多方面的成因联系。粤北下庄铀矿田位于位于南岭铀-多金属成矿带的南部，是华南地区典型的花岗岩型热液铀矿区，本次研究在深入细致的野外地质工作的基础上，运用流体包裹体地球化学、元素地球化学、同位素地球化学等方法手段，开展了对下庄铀矿田成矿流体性质、成矿过程中元素的活动规律、成矿流体来源及演化等方面的系统研究，初步探讨了岩石圈伸展对该区铀成矿的制约机制，并建立了可能的矿床成因模式。通过研究，本次工作获得了以下几点主要认识： （1）通过对下庄铀矿田部分铀矿床流体包裹体显微测温、激光拉曼光谱及液相成分分析研究，查明了下庄矿田铀矿床矿前期热液属中高温（200℃~350℃）、低盐度（0.72%~5.95%NaCl）、密度中等（0.703~0.830g/cm3）、活动深度较深（2.29km~5.74km）、富∑CO2、相对还原性质的流体；成矿期热液属中低温（主要为154℃ ~250℃）、低盐度（0~1.83%NaCl）、密度中等（0.628~0.867g/cm3）、活动深度较浅（0.19km~1.62km）、富F-、相对氧化性质的流体。 （2）矿石矿矿物电子探针测试分析及岩、矿石的微量元素地球化学分析研研究表明，本区铀矿床主要的原生铀矿物为沥青铀矿、铀石、钛铀矿，铀矿物的形成与Si、Ca���W等元素有密切的关系，而其它金属元素未显示明显地富集。矿石、脉石矿物部分继承了原岩的稀土元素组成，且在原岩基础上又有高度的演化。 （3）进行了矿区内碳酸盐的C、O同位素和黄铁矿的He、Ar稀有气体同位素的分析研究。研究表明，矿化剂∑CO2主要为幔源，大量的He、Ar等稀有气体也来自于地幔。矿区发育的深大断裂构造可能控制了幔源挥发份的加入。 （4）脉石矿物碳酸盐和萤石的Sr、Nd同位素地球化学研究显示，成矿流体中的这些元素主要源于地壳，南区矿床（338、339）的Sr、Nd组成则为富含壳源Sr、Nd的流体与幔源基性脉岩不同程度的水—岩反应所致。另外，碳酸盐铅同位素研究显示，下庄矿区成矿物质铀可能来自帽峰式后期流体交代的花岗岩体。 （5）岩石圈伸展与下庄矿田铀成矿有关系密切：下庄矿田铀矿床明显受伸展构造控制，伸展构造既为导矿构造，又为储矿构造；岩石圈伸展导致的地温梯度升高，大地热流平均值加大，驱动热液流体的流动，为铀成矿提供了主要的热驱动力；岩石圈伸展产生的深大断裂导通了壳幔间的联系，使幔源脱气成因挥发份（主要为∑CO2）沿断裂上升，加入壳源热水循环系统，从而参与了铀成矿。 （6）初步建立了下庄矿田“岩石圈伸展体系下大陆热水系统铀矿床成因模式”。模式认为，华南地区白垩—古近纪岩石圈伸展作用引发区内热水流体的大规模循环，且伸展引起的幔源脱气作用产生的挥发份（主要为ΣCO2）加入了贫铀、贫矿化剂的循环的地下热水中，形成了富矿化剂热水。富矿化剂热水从富铀花岗岩中浸出铀（氧化作用），变为富矿化剂、富铀热液流体，这种热液流体在伸展引起的热驱动下沿构造上升，热液流体上升到浅部时，由于地球化学障、流体压力释放等因素的影响，U被还原沉淀，并在有利部位富集成矿。

海洋生物碳酸盐硼同位素技术研究及其应用

近些年来，利用海洋生物碳酸盐硼同位素重建古海水pH，计算当时大气CO2含量，进而推测古气候的变化已成为国际同位素地球化学界研究的热点问题，被称为δ11B-pH技术。古海水的δ11Bsw是否恒定、B(OH)4−和B(OH)3间理论的硼同位素分馏系数4/3是多少以及碳酸盐的δ11Bcarb是否等于海水B(OH)4−的δ11B4值是该技术成功的三个关键。但到目前为止以上三项问题还没得到完全证实。 为确定方解石的硼同位素组成与海水pH的依赖关系，已进行过大量实验研究。他们的结果与预期的假设一致，支持了B(OH)4-是掺入方解石结构主要形式的假设。但近期 Pagani(2005)指出B(OH)4-也许不是掺入方解石结构的主要形式，B(OH)3也可能同时掺入进碳酸盐。肖应凯等(2006)的无机碳酸盐沉积实验发现碳酸盐沉积和母液间的硼同位素分馏系数大于1的异常现象，认为碳酸钙中镁或其它微量元素的存在是重要原因，推断这是在高pH生成Mg(OH)2沉积后11B优先掺入的缘故，推断有B(OH)3掺入碳酸盐的可能。 以前进行的沉积实验，只考虑到碳酸钙本身，确实证明了硼只以或主要以B(OH)4-参与进生物碳酸钙。但天然的海洋生物碳酸盐含有镁、锶、铁等微量元素，这些微量元素的存在可能会改变硼的参与行为，从而对硼同位素分馏产生影响。现代珊瑚礁中水镁石普遍存在，这是否会影响珊瑚的硼同位素组成而导致δ11B-pH技术的误差还值得研究。 针对以上问题，主要对硼掺入进Mg(OH)2的形式及分馏机理，现代珊瑚中镁、锶等微量元素与硼浓度及硼同位素的关系进行研究，并用生物碳酸盐的硼同位素对陆相产出有孔虫的沉积环境进行判别。 通过研究，得到以下几点认识： 1. 在Mg(OH)2从pH9.5～13的含硼合成海水中沉积时，Mg(OH)2沉积11B的变化范围为-1.20‰～28.26‰，高于合成海水的11B (-7.00±0.07‰)，沉积和海水间的硼同位素分馏系数固/液变化范围为1.0177～1.0569，平均值为1.0329，这是H3BO3优先掺入的结果，造成11B在Mg(OH)2沉积中富集。 2. Mg(OH)2沉积的硼浓度和硼在Mg(OH)2沉积与滤液间的分配系数Kd的变化范围分别为228.61 g/g～937.79 g/g和9.31～494.20。高pH值时硼掺入Mg(OH)2的过程中吸附作用占有重要位置。 3. Mg(OH)2吸附实验表明，硼掺入Mg(OH)2非常迅速，4 h能达到平衡。平衡后Mg(OH)2中硼浓度[B]固和固相与溶液相间的分配系数Kd随pH设定的升高和固液比的降低而降低。而且最高的[B]固和Kd均远高于硼被金属氧化物或粘土矿物吸附时的对应值，表硼具有很强的掺入Mg(OH)2的能力。 4. 吸附平衡时溶液相的11B液f (-19.2‰～-17.8‰)均低于原始溶液的11B液i (-7.00±0.07‰)，计算的Mg(OH)2与平衡溶液间的硼同位素分馏系数固-液变化范围为1.0186～1.0220，平均值为1.0203。这充分表明，硼掺入Mg(OH)2时11B优先进入固相，这是B(OH)3优先掺入的结果。 5. 硼以B(OH)3和B(OH)4-两种形式同时掺入Mg(OH)2，并以B(OH)3优先掺入为主，pH设定越低掺入的B(OH)3比例越高。 6. 硼将通过吸附和与Mg(OH)2的沉淀反应而掺入Mg(OH)2，两者共同决定了Mg(OH)2中硼同位素分馏特征。 7. Ca���Sr、B和Na在珊瑚中均得到富集，而Mg在珊瑚中却是贫化的。珊瑚的B浓度主要不是由这几种元素决定的。 8. 珊瑚δ11Bcarb的变化范围为22.8‰～27.9‰，平均为25.2‰。除与B浓度相关性明显外，珊瑚δ11Bcarb与其它四种元素的相关性不强。北海涠洲岛、灯楼角和三亚三地珊瑚与海水间的分馏系数carb-sw分别为0.9839、0.9847和0.9850。珊瑚与海水B(OH)3间的分馏系数carb-3的变化范围为0.9772～0.9800，平均值为0.9788，随pH升高carb-3减小。珊瑚的平均δ11Bcarb基本位于采用=0.9772时理论计算的δ11B4曲线之上，而且都低于原始合成海水的δ11Bcarb，表明硼是以B(OH)3和B(OH)4-两种形式同时掺入进珊瑚中的，并以B(OH)4-优先掺入为主。 9. 由于B(OH)4- 和B(OH)3同时进入到珊瑚中，d11Bcarb=d11B4的假设不能成立，由所测定生物碳酸盐的δ11Bcarb值计算的海水pH值会产生误差，使δ11B-pH技术变得更为复杂。 10. 实验模拟与自然的真实情况是有差距的，不能完全用实验模拟来代替自然的真实情况。 11.杨户庄剖面的第四纪早期有孔虫的生存环境是非海相环境，不是“海侵”或“海泛”的结果；同时也表明有孔虫并非是特有的海洋生物，它完全可以在陆相环境中存在。

Girolando breed genetic improvement program - Sire summary - Progeny test results - July/2015.

The Girolando breed progeny test was established in 1997, as a result of the partnership between Girolando and Embrapa Dairy Cattle. In 2007, the Programa de Melhoramento Genético da Raça Girolando? PMGG (Genetic Improvement Program of the Girolando Breed) was implemented. Besides interacting with previously existing initiatives of the Girolando Breeders Association, such as the genealogical register service, the progeny test and the dairy control service, the PMGG launched the Linear Evaluation System (SLAG). The main objectives of the PMGG comprises identification of genetically superior individuals, the technically-oriented multiplication of genetics, the evaluation of economic traits and the promotion of sustainable dairy activities. The program have yielded impressive results. The Girolando breed semen sales increases faster than any other breed in Brazil.

DECOMPOSITION PRODUCTS OF TRINUCLEAR RUTHENIUM COMPLEXES AS EFFECTIVE CATALYSTS OF WATER OXIDATION

Ruthenium red, a di-mu-oxo-bridged ruthenium complex, and its oxidised form, ruthenium brown, have been studied as possible homogeneous redox catalysts for the oxidation of water to O2 by Ce(IV) ions in H2SO4 and HCIO4. In both media the Ce(IV) ions oxidised the ruthenium red to brown and, with excess of Ce(IV), decomposed the ruthenium brown irreversibly to product(s) with three weak absorption bands at 390, 523 and 593 nm. Only in HCIO4 did the decomposition product(s) appear to act as a stable O2 catalyst. Spectral evidence tentatively suggests that the active catalyst may be a hydrolysed Ru(IV) polymeric species. The rate of catalysis was proportional to the initial concentration of ruthenium red/brown and the activation energy was determined as 36 +/- 1 kJ mol-1 over the temperature range ambient to ca. 50-degrees-C. At temperatures greater than 50-degrees-C the O2 catalyst undergoes an irreversible thermal decomposition reaction.

A 50,000-year record of Late Pleistocene tropical vegetation and human impact in lowland Borneo.

There has been considerable uncertainty about the nature of Pleistocene environments colonised by the first modern humans in Island SE Asia, and about the vegetation of the Last Glacial Maximum (LGM) in the region. Here, the palynology from a series of exposures in the Great Cave of Niah, Sarawak, Malaysian Borneo, spanning a period from ca. 52,000 to 5000 BP is described. Vegetation during this period was climate-driven and often highly unstable. Interstadials are marked by lowland forest, sometimes rather dry and at times by mangroves. Stadials are indicated by taxa characteristic of open environments or, as at the LGM, by highly disturbed rather open forest. Stadials are also characterised by taxa now restricted to 1000-1600 m above sea level, suggesting temperature declines of ca 7-9 C relative to present, by comparison with modern lapse rates. The practice of biomass burning appears associated with the earliest human activity in the cave.

Genotypic subgrouping of clinical isolates of Candida albicans and Candida dubliniensis by 25S intron analysis

To determine the frequency, distribution and association of genotypes of Candida albicans and C. dubliniensis in invasive and noninvasive clinical isolates.

Ordered 180 degrees ferroelectric domains in epitaxial submicron structures

Large range ordered La(0.7)Sr(0.3)MnO(3) and SrRuO(3) epitaxial dots were fabricated by pulsed laser deposition using stencil masks and were embedded in ferroelectric PbTiO(3) epitaxial films. PbTiO(3) films grown on top of La(0.7)Sr(0.3)MnO(3) dots form arrays of 180 degrees domains that are switchable and have good ferroelectric properties. PbTiO(3) films made on top of SrRuO(3) dots have a monodomain polarization state. These observations point out the importance of the electronic properties of the bottom electrode in the selection of a preferential polarization state in epitaxial ferroelectric films and propose a route of fabricating large arrays of switchable 180 degrees ferroelectric domains. (C) 2011 American Institute of Physics. [doi:10.1063/1.3630232]

Cystic Fibrosis from Laboratory to Bedside: The Role of A20 in NF-κB-Mediated Inflammation

Cystic fibrosis (CF) is a lifelong, inflammatory multi-organ disease and the most common lethal, genetic condition in Caucasian populations, with a median survival rate of 41.5 years. Pulmonary disease, characterized by infective exacerbations, bronchiectasis and increasing airway insufficiency is the most serious manifestation of this disease process, currently responsible for over 80% of CF deaths. Chronic dysregulation of the innate immune and host inflammatory response has been proposed as a mechanism central to this genetic condition, primarily driven by the nuclear factor κB (NF-κB) pathway. Chronic activation of this transcription factor complex leads to the production of pro-inflammatory cytokines and mediators such as IL-6, IL-8 and TNF-α. A20 has been described as a central and inducible negative regulator of NF-κB. This intracellular molecule negatively regulates NF-κB-driven pro-inflammatory signalling upon toll-like receptor activation at the level of TRAF6 activation. Silencing of A20 increases cellular levels of p65 and induces a pro-inflammatory state. We have previously shown that A20 expression positively correlates with lung function (FEV1%) in CF. Despite improvement in survival rates in recent years, advancements in available therapies have been incremental. We demonstrate that the experimental use of naturally occurring plant diterpenes such as gibberellin on lipopolysaccharide-stimulated cell lines reduces IL-8 release in an A20-dependent manner. We discuss how the use of a novel bio-informatics gene expression connectivity-mapping technique to identify small molecule compounds that similarly mimic the action of A20 may lead to the development of new therapeutic approaches capable of reducing chronic airway inflammation in CF. 

RECUEIL DES ŒUVRES POÉTIQUES de Jehan Molinet. Ms. in-fol. sur papier de 201 f., demi-rel. v. f, tr. r. (Rel. du XVIIIe siècle.)

Complainte (La) de Grece

Autre exemplaire de la relation contenue dans le ms. français 5094. Cet exemplaire est dédié à Charles de Bourbon, celui qui devait bientôt être nommé connétable de France par le roi François Ier. La dédicace est en 12 vers. Premier vers (fol. C. v°).

Même ornementation, mêmes armoiries que dans le ms. français 5094. « Très noble duc de Bourbon et d'Auvergne,... ».

Resolución N° 212 del 10 de septiembre de 2007 ¿Cuáles son los presupuestos sobre los que se basa la Cámara de Comercio para el registro de providencias judiciales?

Servicios registrales

Microstructural and geochemical investigation of North American lower-middle Paleozoic trilobites and recent arthropods

Trilobites ¥tere collected from Ordovician and Devonian formations of Ontario} New York} Ohio} Oklahoma} and Indiana. Diversity was generally low} but 19..?telllS and Ph..~tY>ps ¥tere the most abundant species from the Ordovician and Devonian} respectively. Recent marine arthropods ¥tere collected from the Atlantic shore of the middle Florida Keys} and from the Pacific and lagoonal waters at Cape Beale} B. C. Fresh-water arthropods were collected along the shore of the Severn River in northcentral Ontario. Cuticles ¥tere analyzed for major} minor and trace elements, 180 and 13C isotopes, as ¥tell as examined by scanning electron micr?scope to identify original and diagenetic fabrics. Examination of trilobite cuticles by scanning electron microscope revealed several microstructures consistent with those observed in Recent arthropods. Microstructures} such as setae and tegumental gland duct openings} in like sized Lim/IllS and Isoteline trilobites may indicate common ancestral origins for these organisms, or simply parallel cuticle evolutions. The dendritic microstructure, originally' thought to be a diagenetic indicator, was found in Recent specimens and therefore its presence in trilobites may be suggestive of the delicate nature of diagenesis in trilobites. The absence of other primary microstructures in trilobites may indicate alteration, taxonomic control} or that there is some inherent feature of S EM examination which may' not allow detection of some features} while others are apparently visit·le onl~1 under SH.·1. The region of the cuticle sampled for examination is also a major influence in detecting pristine microstructures, as not all areas of trilobite and Recent arthropod cuticles will have microstructures identifiable in a SEM study. Subtleties in the process of alteration, however} ma~·· leave pristine microstructures in cuticles that are partial~/ silicified or do 10m itized, and degree and type of alteration may vary stratigraphically and longitudinally within a unit. The presence of fused matrices, angular calcite rhombs, and pyrite in the cuticle are thought to be indicative of altered cuticles, although pyritization may not affect the entire cuticle. t-~atural processes in Recent arthropods, such as molting, lead to variations in cuticle chemistries, and are thought to reflect the area of concentration of the elements during calcification. The level of sodium in Recent arthropods was found to be higher than that in trilobites, but highly mobile when sUbjected to the actions of VY'€'athering. Less saline water produced lovy'€'r magnesium and higher calcium values in Recent specimens .. and metal variations in pristine Ordovician trilobite cuticle appears to follow the constraints outlined for Recent arthropods, of regulation due to the chemislry of the surrounding medium. In diagenetic analysis, sodium, strontium and magnesium proved most beneficial in separating altered from least altered trilobites. Using this criterion, specimens from shale show the least amount of geochemical alteration, and have an original mineralogy of 1.7 - 2.4 mole % MgC03 (8000 t(> 9500 ppm magnesium) for both /s>..?/e/11S lJA'i.riff!11S and PseIAit'11J17ites I..itmirpin..itl/~ and 2.8 - 3.3 mole % MgC03 (5000 to 7000 ppm magnesium) for Ph.i{).?PS This is Slightly lower than the mineralogy of Recent marine arthropods (4.43 - 12.1 mole % MgC03), and slightly higher than that of fresh-water crayfish (0.96 - 1.82 mole % MgC03). Geochemically pristine trilobites were also found to possess primary microstructures. Stable isotope values and trends support the assertion that marine-meteoriclburial fluids were responsible for the alteration observed in a number of the trilobite specimens. The results of this stUdy suggest that fossil material has to be evaluated separately along taxonomic and lithological lines to arrive at sensible diagenetic and e nvironmenta I interpretations.