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Sample records for rare earthiii complexation

  1. Discovery of rare variants for complex phenotypes.

    PubMed

    Kosmicki, Jack A; Churchhouse, Claire L; Rivas, Manuel A; Neale, Benjamin M

    2016-06-01

    With the rise of sequencing technologies, it is now feasible to assess the role rare variants play in the genetic contribution to complex trait variation. While some of the earlier targeted sequencing studies successfully identified rare variants of large effect, unbiased gene discovery using exome sequencing has experienced limited success for complex traits. Nevertheless, rare variant association studies have demonstrated that rare variants do contribute to phenotypic variability, but sample sizes will likely have to be even larger than those of common variant association studies to be powered for the detection of genes and loci. Large-scale sequencing efforts of tens of thousands of individuals, such as the UK10K Project and aggregation efforts such as the Exome Aggregation Consortium, have made great strides in advancing our knowledge of the landscape of rare variation, but there remain many considerations when studying rare variation in the context of complex traits. We discuss these considerations in this review, presenting a broad range of topics at a high level as an introduction to rare variant analysis in complex traits including the issues of power, study design, sample ascertainment, de novo variation, and statistical testing approaches. Ultimately, as sequencing costs continue to decline, larger sequencing studies will yield clearer insights into the biological consequence of rare mutations and may reveal which genes play a role in the etiology of complex traits. PMID:27221085

  2. A Rare Terminal Dinitrogen Complex of Chromium

    SciTech Connect

    Mock, Michael T.; Chen, Shentan; Rousseau, Roger J.; O'Hagan, Molly J.; Dougherty, William G.; Kassel, W. S.; DuBois, Daniel L.; Bullock, R. Morris

    2011-10-12

    The reduction of dinitrogen to ammonia from N2 and H2 is currently carried out by the Haber-Bosch process, an energy intensive process that requires high pressures and high temperatures and accounts for the production of millions of tons of ammonia per year. The development of a catalytic, energy-efficient process for N2 reduction is of great interest and remains a formidable challenge. In this communication, we are reporting the preparation, characterization and computational electronic structure analysis of a rare 'Chatt-type' ((P-P)2M(N2)2, P-P = diphosphine ligand) complex of chromium, cis-[Cr(N2)2(PPh2NBn2)2] and its reactivity with CO. This complex is supported by the diphosphine ligand PPh2NBn2, containing non-coordinating pendant amine bases, to serve as proton relays. Future studies for this complex are aimed at answering fundamental questions regarding the role of proton relays in the second coordination sphere in their ability to facilitate proton movement from an external acid to metal-bound dinitrogen ligands in the challenging multi-proton/electron reduction of N2 to ammonia.

  3. Identifying rare variants associated with complex traits via sequencing

    PubMed Central

    Li, Bingshan; Liu, Dajiang J.; Leal, Suzanne M.

    2013-01-01

    Although genome-wide association studies have been successful in detecting associations with common variants, there is currently an increasing interest in identifying low frequency and rare variants associated with complex traits. Next-generation sequencing technologies make it feasible to survey the full spectrum of genetic variation in coding regions or the entire genome. Due to the low frequency of rare variants, coupled with allelic heterogeneity, however, the association analysis for rare variants is challenging and traditional methods are ineffective. Recently a battery of new statistical methods has been proposed for identifying rare variants associated with complex traits. These methods test for associations by aggregating multiple rare variants across a gene or a genomic region, or a group of variants in the genome. In this Unit, we describe key concepts for rare variant association for complex traits, survey some of the recent methods and discuss their statistical power under various scenarios, and provide practical guidance on analyzing next-generation sequencing data for identifying rare variants associated with complex traits. PMID:23853079

  4. A rare terminal dinitrogen complex of chromium

    SciTech Connect

    Mock, Michael T.; Chen, Shentan; Rousseau, Roger; O'Hagan, Molly; Dougherty, William G.; Kassel, W. Scott; DuBois, Daniel L.; Bullock, R. Morris

    2011-10-12

    Cis and trans-Cr–N₂ complexes supported by the diphosphine ligand P{sup Ph}₂N{sup Bn}₂ have been prepared. Positioned pendant amines in the second coordination sphere influence the thermodynamically preferred geometric isomer. Electronic structure calculations indicate negligible Cr–N₂ back-bonding; rather, electronic polarization of N₂ ligand is thought to stabilize Cr–N₂ binding.

  5. Unusually large erupted complex odontoma: A rare case report

    PubMed Central

    Kukreja, Rahul; Suma, Gundareddy N.; Yadav, Bhawna; Sharma, Havi

    2015-01-01

    Odontomas are nonaggressive, hamartomatous developmental malformations composed of mature tooth substances and may be compound or complex depending on the extent of morphodifferentiation or on their resemblance to normal teeth. Among them, complex odontomas are relatively rare tumors. They are usually asymptomatic in nature. Occasionally, these tumors become large, causing bone expansion followed by facial asymmetry. Odontoma eruptions are uncommon, and thus far, very few cases of erupted complex odontomas have been reported in the literature. Here, we report the case of an unusually large, painless, complex odontoma located in the right posterior mandible. PMID:25793183

  6. Unusually large erupted complex odontoma: A rare case report.

    PubMed

    Bagewadi, Shivanand B; Kukreja, Rahul; Suma, Gundareddy N; Yadav, Bhawna; Sharma, Havi

    2015-03-01

    Odontomas are nonaggressive, hamartomatous developmental malformations composed of mature tooth substances and may be compound or complex depending on the extent of morphodifferentiation or on their resemblance to normal teeth. Among them, complex odontomas are relatively rare tumors. They are usually asymptomatic in nature. Occasionally, these tumors become large, causing bone expansion followed by facial asymmetry. Odontoma eruptions are uncommon, and thus far, very few cases of erupted complex odontomas have been reported in the literature. Here, we report the case of an unusually large, painless, complex odontoma located in the right posterior mandible. PMID:25793183

  7. The Brugada Syndrome: A Rare Arrhythmia Disorder with Complex Inheritance

    PubMed Central

    Gourraud, Jean-Baptiste; Barc, Julien; Thollet, Aurélie; Le Scouarnec, Solena; Le Marec, Hervé; Schott, Jean-Jacques; Redon, Richard; Probst, Vincent

    2016-01-01

    For the last 10 years, applying new sequencing technologies to thousands of whole exomes has revealed the high variability of the human genome. Extreme caution should thus be taken to avoid misinterpretation when associating rare genetic variants to disease susceptibility. The Brugada syndrome (BrS) is a rare inherited arrhythmia disease associated with high risk of sudden cardiac death in the young adult. Familial inheritance has long been described as Mendelian, with autosomal dominant mode of transmission and incomplete penetrance. However, all except 1 of the 23 genes previously associated with the disease have been identified through a candidate gene approach. To date, only rare coding variants in the SCN5A gene have been significantly associated with the syndrome. However, the genotype/phenotype studies conducted in families with SCN5A mutations illustrate the complex mode of inheritance of BrS. This genetic complexity has recently been confirmed by the identification of common polymorphic alleles strongly associated with disease risk. The implication of both rare and common variants in BrS susceptibility implies that one should first define a proper genetic model for BrS predisposition prior to applying molecular diagnosis. Although long remains the way to personalized medicine against BrS, the high phenotype variability encountered in familial forms of the disease may partly find an explanation into this specific genetic architecture. PMID:27200363

  8. Thymic neoplasm: a rare disease with a complex clinical presentation

    PubMed Central

    Rashid, Omar M.; Cassano, Anthony D.

    2013-01-01

    Thymic neoplasms constitute a broad category of rare lesions with a wide spectrum of pathologic characteristics and clinical presentations which therefore require a high index of suspicion to diagnose. The natural history of the disease is seldom predictable, anywhere from an indolent to an aggressively malignant course. Although the classification and staging of these lesions are complex and controversial, complete radical surgical resection remains the gold standard of therapy. Radiation and chemotherapy are important elements of the multimodality approach to treating these patients and it is important for thoracic surgeons to work closely with their colleagues in other disciplines in the management of and future research endeavors in thymic neoplasm. In this review, we discuss the evaluation of the patient with an anterior mediastinal mass, the classification and staging of thymic neoplasms, the role of surgery, radiation and chemotherapy in treating this disease, as well as future directions in research for novel targeted therapies. PMID:23585946

  9. 40 CFR 721.10423 - Complex strontium aluminate, rare earth doped (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... earth doped (generic). 721.10423 Section 721.10423 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10423 Complex strontium aluminate, rare earth doped... substances identified generically as complex strontium aluminate, rare earth doped (PMNs P-12-22, P-12-23,...

  10. Complex Electronic Structure of Rare Earth Activators in Scintillators

    SciTech Connect

    Aberg, D.; Yu, S. W.; Zhou, F.

    2015-10-27

    To aid and further the understanding of the microscopic mechanisms behind the scintillator nonproportionality that leads to degradation of the attainable energy resolution, we have developed theoretical and experimental algorithms and procedures to determine the position of the 4f energy levels of rare earth dopants relative to the host band edge states.

  11. One-dimensional rare earth compounds and complexes: preparation and improved photoluminescence properties.

    PubMed

    Song, Hongwei; Pan, Guohui; Bai, Xue; Li, Suwen; Yu, Hongquan; Zhang, Hui

    2008-03-01

    One-dimensional nanosized phosphors demonstrate special structural and photoluminescence properties, which have application potential in some optical fields. In this article, we present our recent progress on preparation and luminescence properties of some one-dimensional rare earth compounds and complexes, the core-shell oxide nanowires prepared by a two-step hydrothermal route, the nanowires of some inorganic compounds doped with rare earths and rare earth complexes/PVP composites prepared by the electrospinning method, and the rare earth complexes in the SBA-15 mesoporous molecule sieves. In these systems, some novel or improved photoluminescence properties are observed such as improved luminescence quantum yield, thermal stability and/or photostability, and depressed thermal effect in upconversion luminescence. PMID:18468146

  12. Fabrication of Superhydrophobic and Luminescent Rare Earth/Polymer complex Films.

    PubMed

    Wang, Zefeng; Ye, Weiwei; Luo, Xinran; Wang, Zhonggang

    2016-01-01

    The motivation of this work is to create luminescent rare earth/polymer films with outstanding water-resistance and superhydrophobicity. Specifically, the emulsion polymerization of styrene leads to core particles. Then core-shell-structured polymer nanoparticles are synthesized by copolymerization of styrene and acrylic acid on the core surface. The coordination reaction between carboxylic groups and rare earth ions (Eu(3+) and Tb(3+)) generates uniform spherical rare earth/polymer nanoparticles, which are subsequently complexed with PTFE microparticles to obtain micro-/nano-scaled PTFE/rare earth films with hierarchical rough morphology. The films exhibit large water contact angle up to 161° and sliding angle of about 6°, and can emit strong red and green fluorescence under UV excitation. More surprisingly, it is found that the films maintain high fluorescence intensity after submersed in water and even in aqueous salt solution for two days because of the excellent water repellent ability of surfaces. PMID:27086735

  13. Spectroscopy of DABCO-rare-gas and DABCO-DABCO van der Waals complexes

    NASA Astrophysics Data System (ADS)

    van den Hock, G.; Consalvo, D.; Parker, D. H.; Reuss, J.

    1993-03-01

    The excited electronic origin bands of several DABCO containing van der Waals complexes have been observed via (1+1) resonance enhanced multi-photon ionization. Sharp resonances with widths of about 3 cm-1 are seen for DABCO-Rg n=1,2,3 (Rg is Ar, Kr or Xe), for the DABCO-DABCO dimer and for DABCO-DABCO-Ar. The origins of the rare-gas complexes are blue shifted with respect to the monomer origin. Broad features originating from DABCO-Rg n complexes with high n, appear to higher energies than the complex origins, with widths of 120 cm-1.

  14. 78 FR 58311 - Complex Issues in Developing Drug and Biological Products for Rare Diseases; Public Workshop...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Complex Issues in Developing Drug and Biological Products for Rare Diseases; Public Workshop; Request for Comments AGENCY: Food and Drug Administration, HHS. ACTION: Notice of public workshop; request...

  15. Vibration spectra of complexes of rare earth nitrate with some Schiff bases

    NASA Astrophysics Data System (ADS)

    Guofa, Liu

    1994-06-01

    Infrared and Raman spectra of complexes of rare earth nitrate with Schiff bases derived from vanillin (3-methoxy-4-hydroxy-benzaldehyde) or o-vanillin (2-hydroxy-3-methoxy-benzaldehyde) and p-toluidine, 1-naphthylamine, 2-naphthylamine are reported.

  16. Studying the volatility of pyrazolone complexes of rare-earth elements by means of Knudsen effusion

    NASA Astrophysics Data System (ADS)

    Lazarev, N. M.; Petrov, B. I.; Bochkarev, L. N.; Safronova, A. V.; Abakumov, G. A.; Arapova, A. V.; Bessonova, Yu. A.

    2014-08-01

    The temperature dependences of the pressure of saturated vapor of pyrazolone complexes of rare-earth elements Ln(PMIP)3 (where Ln = Y, Ho, Er, Tm, Lu; PMIP = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone) are studied via Knudsen effusion, and the enthalpy of their sublimation is determined. Mass spectra and differential scanning calorimetry data are obtained.

  17. A novel approach for the simultaneous analysis of common and rare variants in complex traits.

    PubMed

    Yuan, Ao; Chen, Guanjie; Zhou, Yanxun; Bentley, Amy; Rotimi, Charles

    2012-01-01

    Genome-wide association studies (GWAS) have been successful in detecting common genetic variants underlying common traits and diseases. Despite the GWAS success stories, the percent trait variance explained by GWAS signals, the so called "missing heritability" has been, at best, modest. Also, the predictive power of common variants identified by GWAS has not been encouraging. Given these observations along with the fact that the effects of rare variants are often, by design, unaccounted for by GWAS and the availability of sequence data, there is a growing need for robust analytic approaches to evaluate the contribution of rare variants to common complex diseases. Here we propose a new method that enables the simultaneous analysis of the association between rare and common variants in disease etiology. We refer to this method as SCARVA (simultaneous common and rare variants analysis). SCARVA is simple to use and is efficient. We used SCARVA to analyze two independent real datasets to identify rare and common variants underlying variation in obesity among participants in the Africa America Diabetes Mellitus (AADM) study and plasma triglyceride levels in the Dallas Heart Study (DHS). We found common and rare variants associated with both traits, consistent with published results. PMID:22346348

  18. Discovery of Rare Variants via Sequencing: Implications for the Design of Complex Trait Association Studies

    PubMed Central

    Li, Bingshan; Leal, Suzanne M.

    2009-01-01

    There is strong evidence that rare variants are involved in complex disease etiology. The first step in implicating rare variants in disease etiology is their identification through sequencing in both randomly ascertained samples (e.g., the 1,000 Genomes Project) and samples ascertained according to disease status. We investigated to what extent rare variants will be observed across the genome and in candidate genes in randomly ascertained samples, the magnitude of variant enrichment in diseased individuals, and biases that can occur due to how variants are discovered. Although sequencing cases can enrich for casual variants, when a gene or genes are not involved in disease etiology, limiting variant discovery to cases can lead to association studies with dramatically inflated false positive rates. PMID:19436704

  19. [Green electroluminescence generated from a new rare earth complex: Tb(asprin)3phen].

    PubMed

    Duan, N; Zhang, X; Gao, X; Liu, S; Xu, X; Tao, D; Xu, Y; Wu, J

    2001-06-01

    Pure Green and narrow bandwidth emission from organic electroluminescent device was presented by using a new rare earth complex Tb(asprin)3phen as emissive layer. The structure of the device was ITO/PVK:Tb(asprin)3phen/Al, where PVK was used to improve the film-forming ability and conductivity of Tb(asprin)3phen. The electroluminescent property of the device was studied. It proved that this new kind of rare earth complex has excellent optoluminescent and electroluminescent properties. The electroluminescent mechanism of the device was proposed by measuring and analyzing the emission and excitation spectra of the emissive layer. The excitation spectrum of Tb(asprin)3phen-dispersed PVK film was very similar to that of the PVK. We proposed that the excited carriers of PVK and Tb(asprin)3phen were captured by Tb3+ and light was emitted when the electrons and holes recombined at Tb3+. PMID:12947642

  20. Rare Earth Complex as Electron Trapper and Energy Transfer Ladder for Efficient Red Iridium Complex Based Electroluminescent Devices.

    PubMed

    Zhou, Liang; Li, Leijiao; Jiang, Yunlong; Cui, Rongzhen; Li, Yanan; Zhao, Xuesen; Zhang, Hongjie

    2015-07-29

    In this work, we experimentally demonstrated the new functions of trivalent rare earth complex in improving the electroluminescent (EL) performances of iridium complex by codoping trace Eu(TTA)3phen (TTA = thenoyltrifluoroacetone, phen = 1,10-phenanthroline) into a light-emitting layer based on PQ2Ir(dpm) (iridium(III)bis(2-phenylquinoly-N,C(2'))dipivaloylmethane). Compared with a reference device, the codoped devices displayed higher efficiencies, slower efficiency roll-off, higher brightness, and even better color purity. Experimental results demonstrated that Eu(TTA)3phen molecules function as electron trappers due to its low-lying energy levels, which are helpful in balancing holes and electrons and in broadening recombination zone. In addition, the matched triplet energy of Eu(TTA)3phen is instrumental in facilitating energy transfer from host to emitter. Finally, highly efficient red EL devices with the highest current efficiency, power efficiency and brightness up to 58.98 cd A(-1) (external quantum efficiency (EQE) of 21%), 61.73 lm W(-1) and 100870 cd m(-2), respectively, were obtained by appropriately decreasing the doping concentration of iridium complex. At certain brightness of 1000 cd m(-2), EL current efficiency up to 51.94 cd A(-1) (EQE = 18.5%) was retained. Our investigation extends the application of rare earth complexes in EL devices and provides a chance to improve the device performances. PMID:26173649

  1. Stability of rare-earth complexes with acetylacetone and methaccrylic acid in aqueous solution

    SciTech Connect

    Panyushkin, V.T.; Akhrimenko, N.V.

    1995-09-01

    The stability constants for lanthanide (Ln) complexes with methacrylic acid (HL) (log{beta}{sub LnL}{sup Ln}), acetylacetone (HAA) (log{beta}{sub Ln(AA){sub 3}}{sup Ln}), and mixed-ligand complexes (log{beta}{sub LnL(AA){sub 2}}{sup Ln}), [Ln(III)=La, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Er, Yb, Lu] in aqueous solution are determined by potentiometric titration at 25{degrees}C and {mu}=0.1 (KCl). A nonmonotonous change in the stability constants with an increase in the atomic number number of the rare-earth metal is found to occur.

  2. Synthesis and theoretical studies on rare three-coordinate lead complexes.

    PubMed

    Chen, Matthew; Fulton, J Robin; Hitchcock, Peter B; Johnstone, Nick C; Lappert, Michael F; Protchenko, Andrey V

    2007-07-14

    A series of beta-diketiminate lead halide complexes has been synthesised LPbCl (2), LPbBr (3) and LPbI (4) (L = {N(2,6-(i)Pr(2)C(6)H(3))C(Me)}2CH]), which includes a rare example of a three-coordinate lead iodide (4). The chloride and bromide complexes, 2 and 3, are relatively stable in both the solid and solution states, only slowly decomposing to elemental lead over the course of a month in solution, the lead iodide 4 appears to be less stable and decomposes after 3 d in the solid state at ambient temperatures. The lead chloride complex 2 was treated with KN(SiMe3)2 to yield an unusual terminal lead amide complex LPbN(SiMe3)2 (5). Unlike three-coordinate beta-diketiminate transition metal-halide complexes, the ligands are present in a pyramidal arrangement around the lead centre, commonly attributed to the presence of a stereochemically active lone pair. We have investigated the influence of this lone pair on the geometry of the metal halide complexes 2-4, as well as the isostructural germanium and tin complexes (6 and 7, respectively) using DFT calculations. The lone pair in the lead complexes is significantly more diffuse than in the tin and germanium analogues and only a small amount of hybridisation between the 6s and 6p orbitals is observed. PMID:17592593

  3. Complex rare-earth aluminum hydrides: mechanochemical preparation, crystal structure and potential for hydrogen storage.

    PubMed

    Weidenthaler, Claudia; Pommerin, André; Felderhoff, Michael; Sun, Wenhao; Wolverton, Christopher; Bogdanović, Borislav; Schüth, Ferdi

    2009-11-25

    A novel type of complex rare-earth aluminum hydride was prepared by mechanochemical preparation. The crystal structure of the REAlH(6) (with RE = La, Ce, Pr, Nd) compounds was calculated by DFT methods and confirmed by preliminary structure refinements. The trigonal crystal structure consists of isolated [AlH(6)](3-) octahedra bridged via [12] coordinated RE cations. The investigation of the rare-earth aluminum hydrides during thermolysis shows a decrease of thermal stability with increasing atomic number of the RE element. Rare-earth hydrides (REH(x)) are formed as primary dehydrogenation products; the final products are RE-aluminum alloys. The calculated decomposition enthalpies of the rare-earth aluminum hydrides are at the lower end for reversible hydrogenation under moderate conditions. Even though these materials may require somewhat higher pressures and/or lower temperatures for rehydrogenation, they are interesting examples of low-temperature metal hydrides for which reversibility might be reached. PMID:19886669

  4. Constructing bis(porphyrinato) rare earth double-decker complexes involving N-confused porphyrin.

    PubMed

    Zhang, Yuehong; Cao, Wei; Wang, Kang; Jiang, Jianzhuang

    2014-06-28

    Reaction of metal-free N-confused 5,10,15,20-tetrakis(4-chlorophenyl)porphyrin (H2NTClPP) with metal-free 5,10,15,20-tetrakis[(4-tert-butyl)phenyl]porphyrin (H2TBPP) in the presence of M(III)(acac)3·nH2O (acac = acetylacetonate) in refluxing 1,2,4-trichlorobenzene (TCB) led to the isolation of heteroleptic bis(porphyrinato) rare earth compounds M(III)(HNTClPP)(TBPP) (M = La, Pr) (1, 2) in 6.7-10% yield. These represent the first examples of sandwich-type porphyrin rare earth double-decker complexes that involve N-confused porphyrin ligand. Different from their homoleptic bis(porphyrinato) rare earth double-decker counterparts HM(III)(TBPP)2 (M = La, Pr) (3, 4), the acidic proton in the heteroleptic analogues was revealed to localize at the inverted pyrrole nitrogen atom of the N-confused porphyrin ligand on the basis of NMR spectroscopic studies. Nevertheless, their heteroleptic bis(porphyrinato) sandwich molecular nature was confirmed on the basis of single crystal X-ray diffraction analysis over the praseodymium double-decker complex. PMID:24809442

  5. [Photoluminescent and electroluminescent properties of a new rare earth terbium complex].

    PubMed

    Wang, Li; Zhang, Xi-qing; Lin, Peng; Xiong, De-pin; Huang, Shi-hua; Yu, Tian-zhi

    2004-06-01

    Pure green and narrowbandwidth emission from an organic electroluminescent device was presented by using arare earth terbium (III) complex as the emissive layer. The structure of the device was ITO/PVK/Tb/PBD/LiF/Al. It was proved that this new kind of rare earth complex has excellent photoluminescent and electroluminescent properties. The electroluminescent spectrum of the device was very similar to that of the terbium (III) complex film. The electroluminescent mechanism of the device was proposed by measuring and analyzing the spectra and electroluminescent property of the device. It is proposed that the excited carriers of PVK and PBD were captured by Tb3+ and light was emitted when the electrons and holes recombined at Tb3+. PMID:15766172

  6. Accurate, multi-kb reads resolve complex populations and detect rare microorganisms

    PubMed Central

    Sharon, Itai; Kertesz, Michael; Hug, Laura A.; Pushkarev, Dmitry; Blauwkamp, Timothy A.; Castelle, Cindy J.; Amirebrahimi, Mojgan; Thomas, Brian C.; Burstein, David; Tringe, Susannah G.; Williams, Kenneth H.

    2015-01-01

    Accurate evaluation of microbial communities is essential for understanding global biogeochemical processes and can guide bioremediation and medical treatments. Metagenomics is most commonly used to analyze microbial diversity and metabolic potential, but assemblies of the short reads generated by current sequencing platforms may fail to recover heterogeneous strain populations and rare organisms. Here we used short (150-bp) and long (multi-kb) synthetic reads to evaluate strain heterogeneity and study microorganisms at low abundance in complex microbial communities from terrestrial sediments. The long-read data revealed multiple (probably dozens of) closely related species and strains from previously undescribed Deltaproteobacteria and Aminicenantes (candidate phylum OP8). Notably, these are the most abundant organisms in the communities, yet short-read assemblies achieved only partial genome coverage, mostly in the form of short scaffolds (N50 = ∼2200 bp). Genome architecture and metabolic potential for these lineages were reconstructed using a new synteny-based method. Analysis of long-read data also revealed thousands of species whose abundances were <0.1% in all samples. Most of the organisms in this “long tail” of rare organisms belong to phyla that are also represented by abundant organisms. Genes encoding glycosyl hydrolases are significantly more abundant than expected in rare genomes, suggesting that rare species may augment the capability for carbon turnover and confer resilience to changing environmental conditions. Overall, the study showed that a diversity of closely related strains and rare organisms account for a major portion of the communities. These are probably common features of many microbial communities and can be effectively studied using a combination of long and short reads. PMID:25665577

  7. Syntheses of new rare earth complexes with carboxymethylated polysaccharides and evaluation of their in vitro antifungal activities.

    PubMed

    Sun, Xiaobo; Jin, Xiaozhe; Pan, Wei; Wang, Jinping

    2014-11-26

    In the present paper, La, Eu and Yb were selected to represent light, middle and heavy rare earths to form complexes with polysaccharides through chelating coordination of carboxyl groups, which were added into polysaccharide chains by means of carboxymethylation. Their antifungal activities against plant pathogenic fungi were evaluated using growth rate method. These rare earth complexes exhibited various antifungal activities against the tested fungi, depending on rare earth elements, polysaccharide types and fungal species. Among these three metal elements (i.e. La, Eu and Yb), Yb formed the complexes with the most effective antifungal properties. Furthermore, the results showed that ligands of carboxymethylated polysaccharides played a key role in promoting cytotoxicity of the rare earth complexes. Carboxymethylated Ganoderma applanatum polysaccharide (CGAP) was found to be the most effective ligand to form complexes with antifungal activities, followed by carboxymethylated lentinan (CLNT) and carboxymethylated Momordica charantia polysaccharide (CMCP). PMID:25256475

  8. Structural Characterisation of Complex Oxide & Rare Earth Manganite Thing Films by Microscopy

    NASA Astrophysics Data System (ADS)

    Jehanathan, Neerushana

    This PhD thesis presents the work on specific complex oxides and rare earth manganite thin films which were characterized mainly by transmission electron microscopy (TEM). The scientific results are divided in two main parts: the first part is devoted to the complex oxide films and the second to the rare earth manganite films. I. Complex oxides: The compositional influence of Cr, Al and Y on the microstructure of Mg-Cr-O, Mg-Al-O, Mg-Y-0 and Y-Al-O films synthesized by a reactive magnetron sputtering technique is reported. The study was based on a series of films with a range of compositions (metal ratios) deposited on Si substrates (without external substrate heating). The film thickness is about 1 μm (±200 nm). The effect of high temperatures (973 K to 1223 K) on the microstructural evolution of Mg-AlO, Mg-Cr-O and Y-Al-O films with specific metal ratios is also reported. II. Rare Earth Manganite Films: The microstructure and defect characterisation of hexagonal ReMnO3 (Re=Y, Tb, Dy, Ho and Er) thin films and multilayers is reported. The effect of off-stoichiometry on the microstructure of some hexagonal ReMnO3 (Re=Er, Dy and Ho) films with specific cationic ratios is also discussed. These thin films and multilayers were deposited on (111) YSZ and (111) Pt/TiO2/SiO 2/Si (stack) substrates by liquid injection metal organic chemical vapour deposition (MOCVD). The thickness of the films and multilayers is between 10 nm and 500 nm.

  9. Von Meyenburg complex and complete ductal plate malformation along with Klatskin tumour: a rare association.

    PubMed

    Gupta, Ashish; Pattnaik, Bramhadatta; Das, Ashim; Kaman, Lileswar

    2016-01-01

    Von Meyenburg complexes (VMCs), or bile duct microhamartomas, are among the constellation of defects of ductal plate malformation. These present as multiple small intrahepatic cysts and are diagnosed incidentally. Association of intrahepatic VMCs with a bile duct cancer has rarely been reported. We describe a case of a 53-year-old man presenting with obstructive jaundice. Biochemistry and radiology gave a provisional diagnosis of a resectable Klatskin tumour. The patient underwent right hepatectomy with common bile duct and caudate lobe excision. The histopathological examination demonstrated intrahepatic VMCs with complete ductal malformation and malignancy at the hilum. PMID:27090552

  10. Rare Earth Metal Complexes of Bidentate Nitroxide Ligands: Synthesis and Electrochemistry.

    PubMed

    Kim, Jee Eon; Bogart, Justin A; Carroll, Patrick J; Schelter, Eric J

    2016-01-19

    We report rare earth metal complexes with tri- and bidentate ligands including strongly electron-donating nitroxide groups. The tridentate ligand 1,3,5-tris(2'-tert-butylhydroxylaminoaryl)benzene (H3arene-triNOx) was complexed to cerium(IV) in a 2:1 ligand-to-metal stoichiometry as Ce(Harene-triNOx)2 (1). Cyclic voltammetry of this compound showed stabilization of the tetravalent cerium cation with a Ce(IV/III) couple at E1/2 = -1.82 V versus Fc/Fc(+). On the basis of the uninvolvement of the third nitroxide group in the coordination chemistry with the cerium(IV) cation, the ligand system was redesigned toward a simpler bidentate mode, and a series of rare earth metal-arene-diNOx complexes were prepared with La(III), Ce(IV), Pr(III), Tb(III), and Y(III), [RE(arene-diNOx)2](-) ([2-RE](-), RE = La, Pr, Y, Tb) and Ce(IV)(arene-diNOx)2, where H2arene-diNOx = 1,3-bis(2'-tert-butylhydroxylaminoaryl)benzene. The core structures were isostructural throughout the series, with three nitroxide groups in η(2) binding modes and one κ(1) nitroxide group coordinated to the metal center in the solid state. In all cases except Ce(IV)(arene-diNOx)2, electrochemical analysis described two subsequent, ligand-based, quasi-reversible redox waves, indicating that a stable [N-O•] group was generated on the electrochemical time scale. Chemical oxidation of the terbium complex was performed, and isolation of the resulting complex, Tb(arene-diNOx)2·CH2Cl2 (3·CH2Cl2), confirmed the assignment of the cyclic voltammograms. Magnetic data showed no evidence of mixing between the Tb(III) states and the states of the open-shell ligand. PMID:26689656

  11. Formation and dynamics of "waterproof" photoluminescent complexes of rare earth ions in crowded environment.

    PubMed

    Ignatova, Tetyana; Blades, Michael; Duque, Juan G; Doorn, Stephen K; Biaggio, Ivan; Rotkin, Slava V

    2014-12-28

    Understanding behavior of rare-earth ions (REI) in crowded environments is crucial for several nano- and bio-technological applications. Evolution of REI photoluminescence (PL) in small compartments inside a silica hydrogel, mimic to a soft matter bio-environment, has been studied and explained within a solvation model. The model uncovered the origin of high PL efficiency to be the formation of REI complexes, surrounded by bile salt (DOC) molecules. Comparative study of these REI-DOC complexes in bulk water solution and those enclosed inside the hydrogel revealed a strong correlation between an up to 5×-longer lifetime of REIs and appearance of the DOC ordered phase, further confirmed by dynamics of REI solvation shells, REI diffusion experiments and morphological characterization of microstructure of the hydrogel. PMID:25379879

  12. Rare Inherited and De Novo CNVs Reveal Complex Contributions to ASD Risk in Multiplex Families.

    PubMed

    Leppa, Virpi M; Kravitz, Stephanie N; Martin, Christa Lese; Andrieux, Joris; Le Caignec, Cedric; Martin-Coignard, Dominique; DyBuncio, Christina; Sanders, Stephan J; Lowe, Jennifer K; Cantor, Rita M; Geschwind, Daniel H

    2016-09-01

    Rare mutations, including copy-number variants (CNVs), contribute significantly to autism spectrum disorder (ASD) risk. Although their importance has been established in families with only one affected child (simplex families), the contribution of both de novo and inherited CNVs to ASD in families with multiple affected individuals (multiplex families) is less well understood. We analyzed 1,532 families from the Autism Genetic Resource Exchange (AGRE) to assess the impact of de novo and rare CNVs on ASD risk in multiplex families. We observed a higher burden of large, rare CNVs, including inherited events, in individuals with ASD than in their unaffected siblings (odds ratio [OR] = 1.7), but the rate of de novo events was significantly lower than in simplex families. In previously characterized ASD risk loci, we identified 49 CNVs, comprising 24 inherited events, 19 de novo events, and 6 events of unknown inheritance, a significant enrichment in affected versus control individuals (OR = 3.3). In 21 of the 30 families (71%) in whom at least one affected sibling harbored an established ASD major risk CNV, including five families harboring inherited CNVs, the CNV was not shared by all affected siblings, indicating that other risk factors are contributing. We also identified a rare risk locus for ASD and language delay at chromosomal region 2q24 (implicating NR4A2) and another lower-penetrance locus involving inherited deletions and duplications of WWOX. The genetic architecture in multiplex families differs from that in simplex families and is complex, warranting more complete genetic characterization of larger multiplex ASD cohorts. PMID:27569545

  13. Preparation and luminescence properties of phosphors of rare earth complexes based on polyoxotungstates

    SciTech Connect

    Wen, He-Rui; Lu, Xiao-Neng; Liao, Jin-Sheng; Zhang, Cai-Wei; You, Hang-Ying; Liu, Cai-Ming

    2015-08-15

    Highlights: • Three new phosphors of rare earth complexes based on polyoxotungstates were synthesized. • [Eu(PW{sub 11}O{sub 39}){sub 2}]{sup 11−} (1) emits red light which used as potential red light materials. • [Sm(PW{sub 11}O{sub 39}){sub 2}] {sup 11−} (2) emits strong orange-red light at 598.7 nm. • [Dy(PW{sub 11}O{sub 39}){sub 2}] {sup 11−} (3) emits white light which used as potential white light materials. - Abstract: Three new phosphors of rare earth complexes based on polyoxotungstates, K{sub 3}Cs{sub 8}[Eu(PW{sub 11}O{sub 39}){sub 2}]·11H{sub 2}O (1), K{sub 3}Cs{sub 8}[Sm(PW{sub 11}O{sub 39}){sub 2}]·10H{sub 2}O (2), and K{sub 5}Cs{sub 6}[Dy(PW{sub 11}O{sub 39}){sub 2}]·15H{sub 2}O (3) have been prepared and characterized. The crystallographic analyses reveal that these compounds consist of two monovacant keggin anions [PW{sub 11}O{sub 39}]{sup 7−} connected by a rare earth ion in a sandwich structure. The investigations of photoluminescence properties show that phosphor 1 emits strong red light at 614 and 702 nm, 2 emits strong orange-red light at 598.7 nm, and 3 exists two strong emissions at 479 nm (blue) and 574 nm (orange). The luminescence properties suggest that the 1 can be applied as the potential red-emitting crystal phosphor, and the 3 may be regarded as a potential white light material for LEDs.

  14. A unique combination of rare mitochondrial ribosomal RNA variants affects the kinetics of complex I assembly.

    PubMed

    Porcelli, Anna Maria; Calvaruso, Maria Antonietta; Iommarini, Luisa; Kurelac, Ivana; Zuntini, Roberta; Ferrari, Simona; Gasparre, Giuseppe

    2016-06-01

    Mitochondrial DNA (mtDNA) mutations in respiratory complexes subunits contribute to a large spectrum of human diseases. Nonetheless, ribosomal RNA variants remain largely under-investigated from a functional point of view. We here report a unique combination of two rare mitochondrial rRNA variants detected by serendipity in a subject with chronic granulomatous disease and never reported to co-occur within the same mitochondrial haplotype. In silico prediction of the mitochondrial ribosomal structure showed a dramatic rearrangement of the rRNA secondary structure. Functional investigation of cybrids carrying this unique haplotype demonstrated that the co-occurrence of the two rRNA variants determines a slow-down of the mitochondrial protein synthesis, especially in cells with an elevated metabolic rate, which impairs the assembly kinetics of Complex I, induces a bioenergetic defect and stimulates reactive oxygen species production. In conclusion, our results point to a sub-pathogenic role for these two rare mitochondrial rRNA variants, when found in the unique combination here reported in a single individual. PMID:27102412

  15. An innovative electronic health records system for rare and complex diseases

    PubMed Central

    2015-01-01

    Background There exists a large number of rare and complex diseases that are neglected due to the difficulty in diagnosis and treatment. Being rare, they normally do not justify the costs of developing an especialized Electronic Health Record (EHR) system to assist doctors and patients of these diseases. In this work we propose the use of Computer applications known as Laboratory Information Management Systems (LIMS) to address this issue. Results In this work we describe a fully customizable EHR system that uses a workflow based LIMS with an easy to adapt interface for data collection and retrieval. This system can easily be customized to manage different types of medical data. The customization for a new disease can be done in a few hours with the help of a specialist. Conclusion We have used the proposed system to manage data from patients of three complex diseases: neuromyelitis optica, paracoccidioidomycosis and adrenoleukodistrofy. These diseases have very different symptoms, exams, diagnostics and treatments, but the FluxMED system is able to manage these data in a highly specialized manner without any modifications to its code. PMID:26695733

  16. Oligomeric rare-earth metal cluster complexes with endohedral transition metal atoms

    SciTech Connect

    Steinberg, Simon; Zimmermann, Sina; Brühmann, Matthias; Meyer, Eva; Rustige, Christian; Wolberg, Marike; Daub, Kathrin; Bell, Thomas; Meyer, Gerd

    2014-11-15

    Comproportionation reactions of rare-earth metal trihalides (RX{sub 3}) with the respective rare-earth metals (R) and transition metals (T) led to the formation of 22 oligomeric R cluster halides encapsulating T, in 19 cases for the first time. The structures of these compounds were determined by single-crystal X-ray diffraction and are composed of trimers ((T{sub 3}R{sub 11})X{sub 15}-type, P6{sub 3}/m), tetramers ((T{sub 4}R{sub 16})X{sub 28}(R{sub 4}) (P-43m), (T{sub 4}R{sub 16})X{sub 20} (P4{sub 2}/nnm), (T{sub 4}R{sub 16})X{sub 24}(RX{sub 3}){sub 4} (I4{sub 1}/a) and (T{sub 4}R{sub 16})X{sub 23} (C2/m) types of structure) and pentamers ((Ru{sub 5}La{sub 14}){sub 2}Br{sub 39}, Cc) of (TR{sub r}){sub n} (n=2–5) clusters. These oligomers are further enveloped by inner (X{sup i}) as well as outer (X{sup a}) halido ligands, which possess diverse functionalities and interconnect like oligomers through i–i, i–a and/or a–i bridges. The general features of the crystal structures for these new compounds are discussed and compared to literature entries as well as different structure types with oligomeric T centered R clusters. Dimers and tetramers originating from the aggregation of (TR{sub 6}) octahedra via common edges are more frequent than trimers and pentamers, in which the (TR{sub r}) clusters share common faces. - Graphical abstract: Rare earth-metal cluster complexes with endohedral transition metal atoms (TR{sub 6}) may connect via common edges or faces to form dimers, trimers, tetramers and pentamers of which the tetramers are the most prolific. Packing effects and electron counts play an important role. - Highlights: • Rare-earth metal cluster complexes encapsulate transition metal atoms. • Oligomers are built via connection of octahedral clusters via common edges or faces. • Dimers through pentamers with closed structures are known. • Tetramers including a tetrahedron of endohedral atoms are the most prolific.

  17. Replication Strategies for Rare Variant Complex Trait Association Studies via Next-Generation Sequencing

    PubMed Central

    Liu, Dajiang J.; Leal, Suzanne M.

    2010-01-01

    There is solid evidence that complex traits can be caused by rare variants. Next-generation sequencing technologies are powerful tools for mapping rare variants. Confirmation of significant findings in stage 1 through replication in an independent stage 2 sample is necessary for association studies. For gene-based mapping of rare variants, two replication strategies are possible: (1) variant-based replication, wherein only variants from nucleotide sites uncovered in stage 1 are genotyped and followed-up and (2) sequence-based replication, wherein the gene region is sequenced in the replication sample and both known and novel variants are tested. The efficiency of the two strategies is dependent on the proportions of causative variants discovered in stage 1 and sequencing/genotyping errors. With rigorous population genetic and phenotypic models, it is demonstrated that sequence-based replication is consistently more powerful. However, the power gain is small (1) for large-scale studies with thousands of individuals, because a large fraction of causative variant sites can be observed and (2) for small- to medium-scale studies with a few hundred samples, because a large proportion of the locus population attributable risk can be explained by the uncovered variants. Therefore, genotyping can be a temporal solution for replicating genetic studies if stage 1 and 2 samples are drawn from the same population. However, sequence-based replication is advantageous if the stage 1 sample is small or novel variants discovery is also of interest. It is shown that currently attainable levels of sequencing error only minimally affect the comparison, and the advantage of sequence-based replication remains. PMID:21129725

  18. Synthesis and structural diversity of trivalent rare-earth metal diisopropylamide complexes.

    PubMed

    Spallek, Tatiana; Heß, Oliver; Meermann-Zimmermann, Melanie; Meermann, Christian; Klimpel, Michael G; Estler, Frank; Schneider, David; Scherer, Wolfgang; Tafipolsky, Maxim; Törnroos, Karl W; Maichle-Mössmer, Cäcilia; Sirsch, Peter; Anwander, Reiner

    2016-09-21

    A series of rare-earth metal diisopropylamide complexes has been obtained via salt metathesis employing LnCl3(THF)x and lithium (LDA) or sodium diisopropylamide (NDA) in n-hexane. Reactions with AM : Ln ratios ≥3 gave ate complexes (AM)Ln(NiPr2)4(THF)n (n = 1, 2; Ln = Sc, Y, La, Lu; AM = Li, Na) in good yields. For smaller rare-earth metal centres such as scandium and lutetium, a Li : Ln ratio = 2.5 accomplished ate-free tris(amido) complexes Ln(NiPr2)3(THF). The chloro-bridged dimeric derivatives [Ln(NiPr2)2(μ-Cl)(THF)]2 (Ln = Sc, Y, La, Lu) could be obtained in high yields for Li : Ln = 1.6-2. The product resulting from the Li : La = 1 : 1.6 reaction revealed a crystal structure containing two different molecules in the crystal lattice, [La(NiPr2)2(THF)(μ-Cl)]2·La(NiPr2)3(THF)2. Recrystallization of the chloro-bridged dimers led to the formation of the monomeric species Ln(NiPr2)2Cl(THF)2 (Ln = Sc, Lu) and La(NiPr2)3(THF)2. The reaction of YCl3 and LDA with Li : Y = 2 in the absence of THF gave a bimetallic ate complex LiY(NiPr2)4 with a chain-like structure. For scandium, the equimolar reactions with LDA or NDA yielded crystals of tetrametallic mono(amido) species, {[Sc(NiPr2)Cl2(THF)]2(LiCl)}2 and [Sc(NiPr2)Cl2(THF)]4, respectively. Depending on the Ln(iii) size, AM, and presence of a donor solvent, ate complexes (AM)Ln(NiPr2)4(THF)n show distinct dynamic behaviour as revealed by variable temperature NMR spectroscopy. The presence of weak LnCH(iPr) β-agostic interactions, as indicated by Ln-N-C angles <105°, is corroborated by DFT calculations and NBO analysis. PMID:27471799

  19. Multiple mycotic aneurysms with a rare fungus, Aspergillus niger: a complex case report.

    PubMed

    Parameswaran, Vatsala

    2008-03-01

    The term "mycotic aneurysm" was first used by William Osler in 1885 to describe a nonsyphilitic bacterial infection of the arterial wall. It is now known that mycotic aneurysm, a rare infectious condition, can arise from a wide variety of clinical causes. The aorta is most often affected; however, such aneurysms may arise in any artery. Mycotic aneurysms are classified as primary (direct extension from surrounding area of infection), secondary (septic embolization that lodges in peripheral arteries), and cryptogenic (unknown cause). A mycotic aneurysm is a threat to life, organs, and limbs. Mycotic aneurysms of the aorta caused by fungi are rare. William Osler used the term "mycotic," referring to all infected aneurysms excluding fungal infections. Yet, the term "mycotic" by definition is a disease caused by a fungus. Only seven cases of aneurysms caused by a fungus were reported from 1966 to 1999. This article will focus on the care of a young female patient with end-stage renal disease receiving peritoneal dialysis who developed a mycotic aneurysm. She was treated with high doses of antifungal medications for the fungus Aspergillus niger. She was switched to hemodialysis from peritoneal dialysis and was later diagnosed with a primary multiple mycotic aneurysms. This article will describe the complex medical, surgical, and nursing care provided to this patient. PMID:18295164

  20. Bis(imidazolin-2-iminato) rare earth metal complexes: synthesis, structural characterization, and catalytic application.

    PubMed

    Trambitas, Alexandra G; Melcher, Daniel; Hartenstein, Larissa; Roesky, Peter W; Daniliuc, Constantin; Jones, Peter G; Tamm, Matthias

    2012-06-18

    Reaction of anhydrous rare earth metal halides MCl(3) with 2 equiv of 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-imine (Im(Dipp)NH) and 2 equiv of trimethylsilylmethyl lithium (Me(3)SiCH(2)Li) in THF furnished the complexes [(Im(Dipp)N)(2)MCl(THF)(n)] (M = Sc, Y, Lu). The molecular structures of all three compounds were established by single-crystal X-ray diffraction analyses. The coordination spheres around the pentacoordinate metal atoms are best described as trigonal bipyramids. Reaction of YbI(2) with 2 equiv of LiCH(2)SiMe(3) and 2 equiv of the imino ligand Im(Dipp)NH in tetrahydrofuran did not result in a divalent complex, but instead the Yb(III) complex [(Im(Dipp)N)(2)YbI(THF)(2)] was obtained and structurally characterized. Treatment of [(Im(Dipp)N)(2)MCl(THF)(n)] with 1 equiv of LiCH(2)SiMe(3) resulted in the formation of [(Im(Dipp)N)(2)M(CH(2)SiMe(3))(THF)(n)]. The coordination arrangement of these compounds in the solid state at the metal atoms is similar to that found for the starting materials, although the introduction of the neosilyl ligand induces a significantly greater distortion from the ideal trigonal-bipyramidal geometry. [(Im(Dipp)N)(2)Y(CH(2)SiMe(3))(THF)(2)] was used as precatalyst in the intramolecular hydroamination/cyclization reaction of various terminal aminoalkenes and of one aminoalkyne. The complex showed high catalytic activity and selectivity. A comparison with the previously reported dialkyl yttrium complex [(Im(Dipp)N)Y(CH(2)SiMe(3))(2)(THF)(3)] showed no clear tendency in terms of activity. PMID:22662762

  1. A major light rare-earth element (LREE) resource in the Khanneshin carbonatite complex, southern Afghanistan

    USGS Publications Warehouse

    Tucker, Robert D.; Belkin, Harvey E.; Schulz, Klaus J.; Peters, Stephen G.; Horton, Forrest; Buttleman, Kim; Scott, Emily R.

    2012-01-01

    The rapid rise in world demand for the rare-earth elements (REEs) has expanded the search for new REE resources. We document two types of light rare-earth element (LREE)-enriched rocks in the Khanneshin carbonatite complex of southern Afghanistan: type 1 concordant seams of khanneshite-(Ce), synchysite-(Ce), and parisite-(Ce) within banded barite-strontianite alvikite, and type 2 igneous dikes of coarse-grained carbonatite, enriched in fluorine or phosphorus, containing idiomorphic crystals of khanneshite-(Ce) or carbocernaite. Type 1 mineralized barite-strontianite alvikite averages 22.25 wt % BaO, 4.27 wt % SrO, and 3.25 wt % ∑ LREE2O3 (sum of La, Ce, Pr, and Nd oxides). Type 2 igneous dikes average 14.51 wt % BaO, 5.96 wt % SrO, and 3.77 wt % ∑ LREE2O3. A magmatic origin is clearly indicated for the type 2 LREE-enriched dikes, and type 1 LREE mineralization probably formed in the presence of LREE-rich hydrothermal fluid. Both types of LREE mineralization may be penecontemporaneous, having formed in a carbonate-rich magma in the marginal zone of the central vent, highly charged with volatile constituents (i.e., CO2, F, P2O5), and strongly enriched in Ba, Sr, and the LREE. Based on several assumptions, and employing simple geometry for the zone of LREE enrichment, we estimate that at least 1.29 Mt (million metric tonnes) of LREE2O3 is present in this part of the Khanneshin carbonatite complex.

  2. Bilateral coronoid hypoplasia and complex odontoma: a rare concurrence of developmental pathology and odontogenic tumour of the mandible.

    PubMed

    Dar, Mohd Arif; Alaparthi, Ravikiran; Yalamanchili, Samatha; Santosh, Arvind Babu Rajendra

    2015-01-01

    We present a rare case of concurrent bilateral coronoid hypoplasia and complex odontoma in the mandible, with replacement of missing posterior teeth in both sides of the lower jaw. A 20-year-old woman was diagnosed with bilateral occurrence of coronoid hypoplasia and unerupted complex odontoma after radiographic and histopathological examination. The patient was surgically treated with complete removal of the unerupted complex odontoma and prosthetic replacement of the missing teeth. PMID:26464410

  3. Strongly luminescent rare-earth-ion-doped DNA-CTMA complex film and fiber materials

    NASA Astrophysics Data System (ADS)

    Wang, Lili; Ishihara, Koki; Izumi, H.; Wada, M.; Zhang, Gongjian; Ishikawa, T.; Watanabe, A.; Horinouchi, Suguru; Ogata, Naoya

    2002-08-01

    A rare-earth chelate, Europium 6,6.7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5,-octanedionate, (Eu3+-FOD) doped DNACTMA complex as fiber and film materials was prepared by casting solution method and gel-spinning method. The Eu-FOD-DNA-CTMA complex was luminescent and has 750 μs of fluorescence lifetime, sharply-spiked emission spectra, excellent film and fiber formability, moderate absorption (40000M-1cm-1) at 327 nm and high quantum yield forlanthanide emission. By comparison of fluorescence lifetime of Eu-FOD doped DNA-CTMA solid matrix with that of Eu-FOD doped in PMMA, it was clear that energy transfer from DNA to FOD leads to enhancement of fluorescence emission at 613 nm. Analysis results for fluorescence spectra and fluorescence relaxation time of Eu3+ doped in the materials indicated that Eu3+-FOD is chemically bond within the DNA-CTMA matrix. Amplified spontaneous emission (ASE) at 612 nm by pumping with UV laser (355 nm) was observed in the materials. Fluorescence lifetime of the Eu-FOD doped in the DNA-CTMA solid matrix was evaluated to be 750 μs, which is ca. 230μs longer than that of Eu-FOD doped in PMMA solid matrix. Efficient Energy transfer from base of DNA to FOD, then to Eu, occurred when irradiated by UV light or 355 laser beams.

  4. (Iminophosphoranyl)(thiophosphoranyl)methane rare-earth borohydride complexes: synthesis, structures and polymerization catalysis.

    PubMed

    Schmid, Matthias; Oña-Burgos, Pascual; Guillaume, Sophie M; Roesky, Peter W

    2015-07-21

    The (iminophosphoranyl)(thiophosphoranyl)methanide {CH(PPh2=NSiMe3)(PPh2=S)}(-) ligand has been used for the synthesis of divalent and trivalent rare-earth borohydride complexes. The salt metathesis of the potassium reagent [K{CH(PPh2=NSiMe3)(PPh2=S)}]2 with [Yb(BH4)2(THF)2] resulted in the divalent monoborohydride ytterbium complex [{CH(PPh2=NSiMe3)(PPh2=S)}Yb(BH4)(THF)2]. The 2D (31)P/(171)Yb HMQC-NMR spectrum clearly showed the coupling between both nuclei. The trivalent bisborohydrides [{CH(PPh2=NSiMe3)(PPh2=S)}Ln(BH4)2(THF)] (Ln = Y, Sm, Tb, Dy, Er, Yb and Lu) were obtained by reaction of [K{CH(PPh2=NSiMe3)(PPh2=S)}]2 with [Ln(BH4)3(THF)3]. All new compounds were characterized by single X-ray diffraction. The divalent and trivalent compounds were next used as initiators in the ring-opening polymerization (ROP) of ε-caprolactone (CL) and trimethylene carbonate (TMC). All complexes afforded a generally well-controlled ROP of both of these cyclic esters. High molar mass poly(ε-caprolactone) diols (Mn,NMR < 101,300 g mol(-1), ĐM = 1.44), and α,ω-dihydroxy and α-hydroxy,ω-formate telechelic poly(trimethylene carbonate)s (Mn,NMR < 20,000 g mol(-1), ĐM = 1.61) were thus synthesized under mild operating conditions. PMID:25683468

  5. Surface structure of the Ag-In-(rare earth) complex intermetallics

    NASA Astrophysics Data System (ADS)

    Hars, S. S.; Sharma, H. R.; Smerdon, J. A.; Yadav, T. P.; Al-Mahboob, A.; Ledieu, J.; Fournée, V.; Tamura, R.; McGrath, R.

    2016-05-01

    We present a study of the surface structure of the Ag-In-RE (RE: rare-earth elements Gd, Tb, and Yb) complex intermetallics using scanning tunneling microscopy and low-energy electron diffraction. The surface of the Ag-In-Yb approximant prepared by sputter-annealing methods under ultrahigh-vacuum conditions produces a flat (100) surface with no facets. However, the Ag-In-Gd and Ag-In-Tb 1/1 approximants, which have a surface miscut of about 12∘ relative to the (100) plane, develop surface facets along various crystallographic directions. The structure of each facet can be explained as a truncation of the rhombic triacontahedral clusters, i.e., the main building blocks of these systems. Despite their differences in atomic structure, symmetry, and density, the facets show common features. The facet planes are In rich. The analysis of the nearest-neighbor atom distances suggests that In atoms form bonds with the RE atoms, which we suggest is a key factor that stabilizes even low-density facet planes.

  6. Rare earth element mineralogy, geochemistry, and preliminary resource assessment of the Khanneshin carbonatite complex, Helmand Province, Afghanistan

    USGS Publications Warehouse

    Tucker, Robert D.; Belkin, Harvey E.; Schulz, Klaus J.; Peters, Stephen G.; Buttleman, Kim P.

    2011-01-01

    There is increased concern about the future availability of rare earth elements (REE) because of China's dominance as the supplier of more than 95 percent of world REE output, their decision to restrict exports of rare earth products, and the rapid increase in world-wide consumption of rare earth product. As a result, countries such as the United States, Japan, and member nations of the European Union face a future of tight supplies and high prices for rare earth products unless other sources of REE are found and developed (Long and others, 2010; U.S. Geological Survey, 2011, p. 128-129, 184-185). We report and describe a significant new deposit of light rare earth elements (LREE), estimated at 1 Mt, within the Khanneshin carbonatite complex of south Afghanistan. The potential resource is located in a remote and rugged part of the igneous complex in a region previously identified by Soviet geologists in the 1970s. This report reviews the geologic setting of LREE deposit, presents new geochemical data documenting the grade of LREE mineralization, briefly describes the mineralogy and mineralogical associations of the deposit, and presents a preliminary estimate of LREE resources based on our current understanding of the geology.

  7. Water-free rare earth-Prussian blue type analogues: synthesis, structure, computational analysis, and magnetic data of {Ln(III)(DMF)(6)Fe(III)(CN)(6)}(infinity) (Ln = rare earths excluding Pm).

    PubMed

    Wilson, Duane C; Liu, Shengming; Chen, Xuenian; Meyers, Edward A; Bao, Xiaoguang; Prosvirin, Andrey V; Dunbar, Kim R; Hadad, Christopher M; Shore, Sheldon G

    2009-07-01

    Water-free rare earth(III) hexacyanoferrate(III) complexes, {Ln(DMF)(6)(mu-CN)(2)Fe(CN)(4)}(infinity) (DMF = N,N-dimethylformamide; Ln = Sm, 1; Eu, 2; Gd, 3; Tb, 4; Dy, 5; Ho, 6; Er, 7; Tm, 8; Yb, 9; Lu, 10; Y, 11; La, 12; Ce, 13; Pr, 14; Nd, 15), were synthesized in dry DMF through the metathesis reactions of [(18-crown-6)K](3)Fe(CN)(6) with LnX(3)(DMF)(n) (X = Cl or NO(3)). Anhydrous DMF solutions of LnX(3)(DMF)(n) were prepared at room temperature from LnCl(3) or LnX(3).nH(2)O under a dynamic vacuum. All compounds were characterized by IR, X-ray powder diffraction (except for 10), and single crystal X-ray diffraction (except for 2, 7, 10). Infrared spectra reveal that a monotonic, linear relationship exists between the ionic radius of the lanthanide and the nu(mu-CN) stretching frequency of 1-10, 12-15 while 11 deviates slightly from the ionic radius relationship. X-ray powder diffraction data are in agreement with powder patterns calculated from single crystal X-ray diffraction results, a useful alternative for bulk sample confirmation when elemental analysis data are difficult to obtain. Eight-coordinate Ln(III) metal centers are observed for all structures. trans-cyanide units of [Fe(CN)(6)](3-) formed isocyanide linkages to Ln(III) resulting in one-dimensional polymeric chains. Structures of compounds 1-9 and 11 are isomorphous, crystallizing in the space group C2/c. Structures of compounds 12-15 are also isomorphous, crystallizing in the space group P2/n. One unique polymeric chain exists in the structures of 1-9 and 11 while two unique polymeric chains exist in structures of 12-15. One of the polymeric chains of 12-15 is similar to that observed for 1-9, 11 while the other is more distorted and has a shorter Ln-Fe distance. Magnetic susceptibility measurements for compounds 3-6, 8, 11 were performed on polycrystalline samples of the compounds. PMID:20507100

  8. Stability constants for the formation of rare earth-inorganic complexes as a function of ionic strength

    NASA Astrophysics Data System (ADS)

    Millero, Frank J.

    1992-08-01

    Recent studies have been made on the distribution of the rare earths (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in natural waters relative to their concentration in shales. These metals have also been used as models for the behavior of the trivalent actinides. The speciation of the rare earths in natural waters is modelled by using ionic interaction models which require reliable stability constants. In this paper the stability constants for the formation of lanthanide complexes ( k mx∗) with Cl -, NO 3-, SO 42-, OH -, HCO 3-, H 2PO 4-, HPO 42-, and CO 32- determined in NaClO 44 at various ionic strengths have been extrapolated to infinite dilution using the Pitzer interaction model. The activity coefficients for free ions ( γM, γx) needed for this extrapolation have been estimated from the Pitzer equations. The thermodynamic stability constants ( KMX) and activity coefficients of the various ion pairs ( γMX) were determined from In ( solK MX∗/γ Mγ x) = In K mx+ In (γ MX). The activity coefficients of the ion pairs have been used to determine Pitzer parameters ( BMX) for the rare earth complexes. The values of BMX were found to be the same for complexes of the same charge. These results make it possible to estimate the stability constants for the formation of rare earth complexes over a wide range of ionic strengths. The stability constants have been used to determine the speciation of the lanthanides in seawater and in brines. The carbonate complexes dominate for all natural waters where the carbonate alkalinity is greater than 0.001 eq/L at a pH near 8.

  9. Rare earth complexes with 3-carbaldehyde chromone-(benzoyl) hydrazone: synthesis, characterization, DNA binding studies and antioxidant activity.

    PubMed

    Li, Yong; Yang, Zheng-Yin

    2010-01-01

    A new ligand, 3-carbaldehyde chromone-(benzoyl) hydrazone (L), was prepared by condensation of 3-carbaldehyde chromone with benzoyl hydrazine. Its four rare earth complexes have been prepared and characterized on the basis of elemental analyses, molar conductivities, mass spectra, (1)H NMR spectra, UV-vis spectra, fluorescence studies and IR spectra. The Sm(III) complex exhibits red fluorescence under UV light and the fluorescent properties of Sm(III) complex in solid state and different solutions were investigated. In addition, the DNA binding properties of the ligand and its complexes have been investigated by electronic absorption spectroscopy, fluorescence spectra, ethidium bromide displacement experiments, iodide quenching experiments, salt effect and viscosity measurements. Experimental results suggest that all the compounds can bind to DNA via an intercalation binding mode. Furthermore, the antioxidant activities of the ligand and its complexes were determined by superoxide and hydroxyl radical scavenging methods in vitro. The rare earth complexes were found to possess potent antioxidant activities that are better than those of the ligand alone. PMID:19856083

  10. Revealing rate-limiting steps in complex disease biology: The crucial importance of studying rare, extreme-phenotype families.

    PubMed

    Chakravarti, Aravinda; Turner, Tychele N

    2016-06-01

    The major challenge in complex disease genetics is to understand the fundamental features of this complexity and why functional alterations at multiple independent genes conspire to lead to an abnormal phenotype. We hypothesize that the various genes involved are all functionally united through gene regulatory networks (GRN), and that mutant phenotypes arise from the consequent perturbation of one or more rate-limiting steps that affect the function of the entire GRN. Understanding a complex phenotype thus entails unraveling the details of each GRN, namely, the transcription factors that bind to cis regulatory elements affected by sequence variants altering transcription of specific genes, and their mutual feedback relationships. These GRNs can be identified through their rate-limiting steps and are best uncovered by genomic analyses of rare, extreme phenotype families, thus providing a coherent molecular basis to complex traits and disorders. PMID:27062178

  11. Reactivity of functionalized indoles with rare-earth metal amides. Synthesis, characterization and catalytic activity of rare-earth metal complexes incorporating indolyl ligands.

    PubMed

    Feng, Zhijun; Wei, Yun; Zhou, Shuangliu; Zhang, Guangchao; Zhu, Xiancui; Guo, Liping; Wang, Shaowu; Mu, Xiaolong

    2015-12-21

    The reactivity of several functionalized indoles 2-(RNHCH2)C8H5NH (R = C6H5 (1), (t)Bu (2), 2,6-(i)Pr2C6H3 (3)) with rare-earth metal amides is described. Reactions of 1 or 2 with [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 (RE = Eu, Yb) respectively produced the europium complexes [2-(C6H5N[double bond, length as m-dash]CH)C8H5N]2Eu[N(SiMe3)2] (4) and [2-((t)BuN[double bond, length as m-dash]CH)C8H5N]Eu[N(SiMe3)2]2 (5), and the ytterbium complex [2-((t)BuN[double bond, length as m-dash]CH)C8H5N]2Yb[N(SiMe3)2] (6), containing bidentate anionic indolyl ligands via dehydrogenation of the amine to the imine. In contrast, reactions of the more sterically bulky indole 3 with [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 afforded complexes [2-(2,6-(i)Pr2C6H3NCH2)C8H5N]RE[N(SiMe3)2](THF)2 (RE = Yb (7), Y (8), Er (9), Dy (10)) with the deprotonated indolyl ligand. While reactions of 3 with yttrium and ytterbium amides in refluxing toluene respectively gave the complexes [2-(2,6-(i)Pr2C6H3N[double bond, length as m-dash]CH)C8H5N]3Y (11) and [2-(2,6-(i)Pr2C6H3N[double bond, length as m-dash]CH)C8H5N]2Yb(II)(THF)2 (12), along with transformation of the amino group to the imino group, and also with a reduction of Yb(3+) to Yb(2+) in the formation of 12. Reactions of 3 with samarium and neodymium amides provided novel dinuclear complexes {[μ-η(5):η(1):η(1)-2-(2,6-(i)Pr2C6H3NCH2)C8H5N]RE[N(SiMe3)2]}2 (RE = Sm (13), Nd (14)) having indolyl ligands in μ-η(5):η(1):η(1) hapticities. The pathway for the transformation of the amino group to the imino group is proposed on the basis of the experimental results. The new complexes displayed excellent activity in the intramolecular hydroamination of aminoalkenes. PMID:26548974

  12. 78 FR 58316 - Complex Issues in Developing Medical Devices for Pediatric Patients Affected by Rare Diseases...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ... inappropriate for pediatric use due to a variety of factors, including patient size, growth, and development, or... practice trends of medical devices in rare disease pediatric populations. For example, how much off-label... pediatric populations? B. HUD/HDE 1. Is there any confusion about the designation process for HUDs or...

  13. Rare-earth metal π-complexes of reduced arenes, alkenes, and alkynes: bonding, electronic structure, and comparison with actinides and other electropositive metals.

    PubMed

    Huang, Wenliang; Diaconescu, Paula L

    2015-09-21

    Rare-earth metal complexes of reduced π ligands are reviewed with an emphasis on their electronic structure and bonding interactions. This perspective discusses reduced carbocyclic and acyclic π ligands; in certain categories, when no example of a rare-earth metal complex is available, a closely related actinide analogue is discussed. In general, rare-earth metals have a lower tendency to form covalent interactions with π ligands compared to actinides, mainly uranium. Despite predominant ionic interactions in rare-earth chemistry, covalent bonds can be formed with reduced carbocyclic ligands, especially multiply reduced arenes. PMID:26247323

  14. HM{sup +}–RG complexes (M = group 2 metal; RG = rare gas): Physical vs. chemical interactions

    SciTech Connect

    Harris, Joe P.; Dodson, Hannah; Wright, Timothy G.; Breckenridge, W. H.

    2015-04-21

    Previous work on the HM{sup +}–He complexes (M = Be–Ra) has been extended to the cases of the heavier rare gas atoms, HM{sup +}–RG (RG = Ne–Rn). Optimized geometries and harmonic vibrational frequencies have been calculated using MP2 theory and quadruple-ζ quality basis sets. Dissociation energies for the loss of the rare gas atom have been calculated at these optimized geometries using coupled cluster with single and double excitations and perturbative triples, CCSD(T)theory, extrapolating interaction energies to the basis set limit. Comparisons are made between the present data and the previously obtained helium results, as well as to those of the bare HM{sup +} molecules; furthermore, comparisons are made to the related M{sup +}–RG and M{sup 2+}–RG complexes. Partial atomic charge analyses have also been undertaken, and these used to test a simple charge-induced dipole model. Molecular orbital diagrams are presented together with contour plots of the natural orbitals from the quadratic configuration with single and double excitations (QCISD) density. The conclusion is that the majority of these complexes are physically bound, with very little sharing of electron density; however, for M = Be, and to a lesser extent M = Mg, some evidence for chemical effects is seen in HM{sup +}–RG complexes involving RG atoms with the higher atomic numbers.

  15. Ligand extraction of rare earth elements from aquifer sediments: Implications for rare earth element complexation with organic matter in natural waters

    NASA Astrophysics Data System (ADS)

    Tang, Jianwu; Johannesson, Karen H.

    2010-12-01

    The ability of organic matter as well as carbonate ions to extract rare earth elements (REEs) from sandy sediments of a Coastal Plain aquifer was investigated for unpurified organic matter from different sources (i.e., Mississippi River natural organic matter, Aldrich humic acid, Nordic aquatic fulvic acid, Suwannee River fulvic acid, and Suwannee River natural organic matter) and for extraction solutions containing weak (i.e., CH 3COO -) or strong (i.e., CO32-) ligands. The experimental results indicate that, in the absence of strong REE complexing ligands in solution, the amount of REEs released from the sand is small and the fractionation pattern of the released REEs appears to be controlled by the surface stability constants for REE sorption with Fe(III) oxides/oxyhydroxides. In the presence of strong solution complexing ligands, however, the amount and the fractionation pattern of the released REEs reflect the strength and variation of the stability constants of the dominant aqueous REE species across the REE series. The varying amount of REEs extracted by the different organic matter employed in the experiments indicates that organic matter from different sources has different complexing capacity for REEs. However, the fractionation pattern of REEs extracted by the various organic matter used in our experiments is remarkable consistent, being independent of the source and the concentration of organic matter used, as well as solution pH. Because natural aquifer sand and unpurified organic matter were used in our experiments, our experimental conditions are more broadly similar to natural systems than many previous laboratory experiments of REE-humic complexation that employed purified humic substances. Our results suggest that the REE loading effect on REE-humic complexation is negligible in natural waters as more abundant metal cations (e.g., Fe, Al) out-compete REEs for strong binding sites on organic matter. More specifically, our results indicate that REE

  16. Single molecule magnet behaviour in a rare trinuclear {Cr(III)Dy} methoxo-bridged complex.

    PubMed

    Car, Pierre-Emmanuel; Favre, Annaïck; Caneschi, Andrea; Sessoli, Roberta

    2015-09-28

    The reaction of the chromium(iii) chloride tetrahydrofuran complex with the dipivaloylmethane ligand, the lanthanide alcoholic salt DyCl3·CH3OH and the 1,1,1-tris(hydroxymethyl)-ethane ligand resulted in the formation of a new trinuclear chromium-dysprosium complex. Magnetic investigations revealed that the new 3d-4f complex exhibits single molecule magnet behaviour. PMID:26282265

  17. Single-Molecule-Magnet Behavior and Fluorescence Properties of 8-Hydroxyquinolinate Derivative-Based Rare-Earth Complexes.

    PubMed

    Gao, Hong-Ling; Jiang, Li; Wang, Wen-Min; Wang, Shi-Yu; Zhang, Hong-Xia; Cui, Jian-Zhong

    2016-09-01

    Five tetranuclear rare-earth complexes, [RE4(dbm)4L6(μ3-OH)2] [HL = 5- (4-fluorobenzylidene)-8-hydroxylquinoline; dbm = 1,3-diphenyl-1,3-propanedione; RE = Y (1), Eu (2), Tb (3), Dy (4), Lu (5)], have been synthesized and completely characterized. The X-ray structural analyses show that each [RE4] complex is of typical butterfly or rhombus topology. Each RE(III) center exists in an eight-coordinated square-antiprism environment. Magnetic studies reveal that complex 4 displays single-molecule-magnet behavior below 10 K under a zero direct-current field, with an effective anisotropy barrier (ΔE/kB = 56 K). The fluorescence properties of complexes 1-5 were also investigated. Complexes 2-4 showed their characteristic peaks for the corresponding RE(III) center, while complexes 1 and 5 showed the same emission peaks with the ligand when they were excited at the same wavelength. PMID:27560459

  18. Single ventricle, bicuspid aorta and interatrial wall aneurysm as a rare complex adult congenital heart disease: a case report

    PubMed Central

    2009-01-01

    Background Single ventricle, bicuspid aortic valve and interatrial wall aneurysm in adulthood are a rare and unique case in medical literature. This presented case with congenital heart disease has never been treated surgically and clinical consequences seriously presented in adulthood. Case presentation A 27 year old man with complex congenital heart disease presented. At the age of six, the single ventricle was ultrasonographly diagnosed, but at age 27 clinical consequences started to be seriously present. We explored his history, clinical course, physical examination, laboratory findings, medical treatments and actual patient condition. Conclusion The possibilities for surgical evaluation are presented. PMID:19183494

  19. Two complex associations of an HBD mutation and a rare α hemoglobinopathy.

    PubMed

    Joly, Philippe; Lacan, Philippe; Garcia, Caroline; Francina, Alain

    2013-01-01

    We present two case reports in which an HBD mutation is present with a rare α hemoglobinopathy that substantially complicates the associated phenotype. In the first case, a new δ-globin variant, Hb A2-Pierre-Bénite [δ83(EF7)Gly→Arg; HBD: c.250G>C] is associated with Hb Groene Hart [α119(H2)Pro→Ser (α1); HBA1: c.358C>T], an α-thalassemic variant. In the second case, a δ(+)-thalassemic variant, δ4(A1)Thr→Ile; HBD: c.14C>T, is associated with a newly described deletion of the hypersensitive site 40 (HS-40) region on the α-globin gene cluster. In both patients, a δ-globin mutation was suspected because of an abnormally low Hb A2 level, whereas the α hemoglobinopathy was sought to explain the slight microcytosis and hypochromia presented by the probands. PMID:23806011

  20. Rare earth element evidence for the petrogenesis of the banded series of the Stillwater Complex, Montana, and its anorthosites

    USGS Publications Warehouse

    Loferski, P.J.; Arculus, R.J.; Czamanske, G.K.

    1994-01-01

    A rare earth element (REE) study was made by isotope-dilution mass spectrometry of plagioclase separates from a variety of cumulates stratigraphically spanning the Banded series of the Stillwater Complex, Montana. Evaluation of parent liquid REE patterns, calculated on the basis of published plagioclase-liquid partition coefficients, shows that the range of REE ratios is too large to be attributable to fractionation of a single magma type. At least two different parental melts were present throughout the Banded series. This finding supports hypotheses of previous workers that the Stillwater Complex formed from two different parent magma types, designated the anorthosite- or A-type liquid and the ultramafic- or U-type liquid. -from Authors

  1. Langmuir-Blodgett film and second harmonic generation of a series of new nonlinear optical rare earth complexes

    NASA Astrophysics Data System (ADS)

    Li, Hui; Huang, Chun-hui; Zhao, Yi-lei; Li, Tian-kai; Bai, Jie; Zhao, Xin-sheng; Xia, Xiao-hua

    1995-06-01

    Four kinds of amphiphilic rare earth complexes containing the new chromophore: 4-[(4-N,N'-diethylamino)phenyl)azo]-1-methyl-pyridinium-Tetrakis(4-benzoyl-1-phenyl-3-methyl-pyrazolone-5) Dysprosium (compound A), 4-[(4-N,N'-(diethylamino)phenyl)azo]-1-methyl-pyridinium-Tri(4-benzoyl-1-phenyl-3-methyl-pyrazolone-5)-(4-hexadecanoyl-1-phenyl-3-methyl Pyrazolone5)Dysprosium(compound B), 4-[(4-N,N'-diethylamino)phenyl)azo]-1-methyl-pyridinium-Tetrakis(2-thenoyl-trifluoroacetone)Dysprosium (compound C) and 4-[(4-N,N'-(diethylamino)phenyl)azo]-1-methyl-pyridinium-Tri(2-thenoyl-trifluoroacetone)-(4-hexadecanoyl-1-phenyl-3-methyl-pyrazolone-5 Dysprosium (compound D), and their iodide (compound E), were synthesized. The film-forming properties of compound A and B are good while compounds C, D and E cannot form stable Langmuir film. The second-order molecular hyperpolarizability β of the rare earth complexes were evaluated to be 1.3×10 -28e.s.u. and 5.9×10 -28e.s.u. for compounds A and B respectively.

  2. Mono(boratabenzene) rare-earth metal dialkyl complexes: synthesis, structure and catalytic behaviors for styrene polymerization.

    PubMed

    Wang, Xiufang; Leng, Xuebing; Chen, Yaofeng

    2015-03-28

    Four mono(boratabenzene) rare-earth metal dialkyl complexes, [(3,5-Me2-C5H3BR)Ln(CH2SiMe3)2(THF)] (1: R = NEt2, Ln = Sc; 2: R = NEt2, Ln = Lu; 3: R = Ph, Ln = Sc; 4: R = Ph, Ln = Lu), were synthesized efficiently via a one-pot strategy with Li[3,5-Me2-C5H3BR] (R = NEt2, Ph), LnCl3(THF)x (Ln = Sc, x = 3; Ln = Lu, x = 0), and LiCH2SiMe3. The solid-state structures of 1 and 2 were determined by single-crystal X-ray diffraction. Variable-temperature NMR studies indicated that the energy barrier for the rotation of aminoboratabenzene in 1 (ΔG‡ ≈ 71 kJ mol−1) is higher than that of phenylboratabenzene in 3 (ΔG‡ ≈ 59 kJ mol−1). These mono(boratabenzene) rare-earth metal dialkyl complexes’ catalytic behaviors for styrene polymerization were investigated, and found that mono(boratabenzene) scandium dialkyl complexes show high catalytic activities for syndiotactic polymerization upon activation with cocatalysts. PMID:25714489

  3. Water-Free Rare Earth-Prussian Blue Type Analogues: Synthesis, Structure, Computational Analysis, and Magnetic Data of {Ln[superscript III](DMF)[subscript 6]Fe[superscript III](CN)[subcsript 6]}[subscript infinity] (Ln = Rare Earths Excluding Pm)

    SciTech Connect

    Wilson, Duane C.; Liu, Shengming; Chen, Xuenian; Meyers, Edward A.; Bao, Xiaoguang; Prosvirin, Andrey V.; Dunbar, Kim R.; Hadad, Christopher M.; Shore, Sheldon G.

    2009-11-04

    Water-free rare earth(III) hexacyanoferrate(III) complexes, {l_brace}Ln(DMF){sub 6}({mu}-CN){sub 2}Fe(CN){sub 4}{r_brace}{sub {infinity}} (DMF = N,N-dimethylformamide; Ln = Sm, 1; Eu, 2; Gd, 3; Tb, 4; Dy, 5; Ho, 6; Er, 7; Tm, 8; Yb, 9; Lu, 10; Y, 11; La, 12; Ce, 13; Pr, 14; Nd, 15), were synthesized in dry DMF through the metathesis reactions of [(18-crown-6)K]{sub 3}Fe(CN){sub 6} with LnX{sub 3}(DMF){sub n} (X = Cl or NO{sub 3}). Anhydrous DMF solutions of LnX{sub 3}(DMF){sub n} were prepared at room temperature from LnCl{sub 3} or LnX{sub 3} {center_dot} nH{sub 2}O under a dynamic vacuum. All compounds were characterized by IR, X-ray powder diffraction (except for 10), and single crystal X-ray diffraction (except for 2, 7, 10). Infrared spectra reveal that a monotonic, linear relationship exists between the ionic radius of the lanthanide and the {nu}{sub {mu}-CN} stretching frequency of 1-10, 12-15 while 11 deviates slightly from the ionic radius relationship. X-ray powder diffraction data are in agreement with powder patterns calculated from single crystal X-ray diffraction results, a useful alternative for bulk sample confirmation when elemental analysis data are difficult to obtain. Eight-coordinate Ln(III) metal centers are observed for all structures. trans-cyanide units of [Fe(CN){sub 6}]{sup 3-} formed isocyanide linkages to Ln(III) resulting in one-dimensional polymeric chains. Structures of compounds 1-9 and 11 are isomorphous, crystallizing in the space group C2/c. Structures of compounds 12-15 are also isomorphous, crystallizing in the space group P2/n. One unique polymeric chain exists in the structures of 1-9 and 11 while two unique polymeric chains exist in structures of 12-15. One of the polymeric chains of 12-15 is similar to that observed for 1-9, 11 while the other is more distorted and has a shorter Ln-Fe distance. Magnetic susceptibility measurements for compounds 3-6, 8, 11 were performed on polycrystalline samples of the compounds.

  4. Fluorescence enhancement of rare earth Tb(III) by Tm(III) in benzyl benzoylmethyl sulphoxide complexes.

    PubMed

    Li, Wen-Xian; Chai, Wen-Juan; Liu, Yu; Li, Ying-Jie; Ren, Tie; Zhang, Jing; Ao, Bo-Yang

    2012-01-01

    A series of rare earth complexes [(Tb(x) Tm(y))L5 (ClO4)2](ClO4)·3H(2) O (x:y = 1.000:0.000, 0.999:0.001, 0.995:0.005, 0.990:0.010, 0.950:0.050, 0.900:0.100, 0.800:0.200, 0.700:0.300; L = C(6) H5 CH2 SOCH2 COC6 H5) (Tb(III) luminescence ion; Tm(III) doped inert ion) were synthesized and characterized by elemental analysis, infrared spectra (IR) and (1) H-NMR. The photophysical properties of these complexes were studied in detail using ultraviolet absorption spectra, fluorescent spectra and lifetimes. The fluorescence spectra of complexes indicated that the fluorescence emission intensity was significantly enhanced by Tm(III). The complexes showed the best luminescence properties when the mole ratio Tb(III):Tm(III) was 0.990:0.010. The fluorescence intensity could be increased to 390%. Additionally, phosphorescence spectra and the luminescence mechanisms are discussed. PMID:22114050

  5. Prenatal diagnosis of body stalk complex: A rare entity and review of literature.

    PubMed

    Kocherla, Keerthi; Kumari, Vasantha; Kocherla, Prasada Rao

    2015-01-01

    Body stalk anomalies are a group of massively disfiguring abdominal wall defects in which the abdominal organs lie outside of the abdominal cavity in a sac of amnioperitoneum with absence of or very small umbilical cord. Various hypotheses proposed to explain the pathogenesis of limb body wall complex include early amnion disruptions, embryonic dysplasia, and vascular disruption in early pregnancy. Body stalk anomaly is an accepted fatal anomaly and, hence, its early diagnosis aids in proper management of the patient. PMID:25709170

  6. Rare-earth-metal methyl, amide, and imide complexes supported by a superbulky scorpionate ligand.

    PubMed

    Schädle, Dorothea; Maichle-Mössmer, Cäcilia; Schädle, Christoph; Anwander, Reiner

    2015-01-01

    The reaction of monomeric [(Tp(tBu,Me) )LuMe2 ] (Tp(tBu,Me) =tris(3-Me-5-tBu-pyrazolyl)borate) with primary aliphatic amines H2 NR (R=tBu, Ad=adamantyl) led to lutetium methyl primary amide complexes [(Tp(tBu,Me) )LuMe(NHR)], the solid-state structures of which were determined by XRD analyses. The mixed methyl/tetramethylaluminate compounds [(Tp(tBu,Me) )LnMe({μ2 -Me}AlMe3 )] (Ln=Y, Ho) reacted selectively and in high yield with H2 NR, according to methane elimination, to afford heterobimetallic complexes: [(Tp(tBu,Me) )Ln({μ2 -Me}AlMe2 )(μ2 -NR)] (Ln=Y, Ho). X-ray structure analyses revealed that the monomeric alkylaluminum-supported imide complexes were isostructural, featuring bridging methyl and imido ligands. Deeper insight into the fluxional behavior in solution was gained by (1) H and (13) C NMR spectroscopic studies at variable temperatures and (1) H-(89) Y HSQC NMR spectroscopy. Treatment of [(Tp(tBu,Me) )LnMe(AlMe4 )] with H2 NtBu gave dimethyl compounds [(Tp(tBu,Me) )LnMe2 ] as minor side products for the mid-sized metals yttrium and holmium and in high yield for the smaller lutetium. Preparative-scale amounts of complexes [(Tp(tBu,Me) )LnMe2 ] (Ln=Y, Ho, Lu) were made accessible through aluminate cleavage of [(Tp(tBu,Me) )LnMe(AlMe4 )] with N,N,N',N'-tetramethylethylenediamine (tmeda). The solid-state structures of [(Tp(tBu,Me) )HoMe(AlMe4 )] and [(Tp(tBu,Me) )HoMe2 ] were analyzed by XRD. PMID:25392940

  7. Double-decker bis(tetradiazepinoporphyrazinato) rare earth complexes: crucial role of intramolecular hydrogen bonding.

    PubMed

    Tarakanova, Ekaterina N; Trashin, Stanislav A; Simakov, Anton O; Furuyama, Taniyuki; Dzuban, Alexander V; Inasaridze, Liana N; Tarakanov, Pavel A; Troshin, Pavel A; Pushkarev, Victor E; Kobayashi, Nagao; Tomilova, Larisa G

    2016-07-26

    A series of homoleptic bis{tetrakis(5,7-bis(4-tert-butylphenyl)-6H-1,4-diazepino)[2,3-b,g,l,q]porphyrazinato}lanthanide sandwich complexes [(tBuPh)DzPz]2Ln (Ln = Lu, Er, Dy, Eu, Nd, Ce, La) were prepared and their physicochemical properties were studied to gain insight into the nature of specific interactions in diazepinoporphyrazines. The effect of annulated diazepine moieties and the Ln ionic radius on the properties of the complexes was investigated in comparison with double-decker phthalocyanines. A combination of experimental and theoretical studies revealed the presence of two types of hydrogen bonding interactions in the metal-free porphyrazine and the corresponding sandwich complexes, namely, interligand C-H(ax)N(meso) hydrogen bonding and O-HN(Dz) ligand-water interaction. The interligand hydrogen bonding imparts high stability of the ligand dimer and the double-decker compounds in a reduced state. This work is the first comprehensive investigation into the fundamental understanding of the unusual properties of diazepine-containing macroheterocycles. PMID:27396712

  8. Mastocytosis: a paradigmatic example of a rare disease with complex biology and pathology

    PubMed Central

    Valent, Peter

    2013-01-01

    Mastocytosis is a rare disease characterized by abnormal expansion and accumulation of tissue mast cells (MC) in one or multiple organs. In most adult patients, systemic mastocytosis (SM) is diagnosed. Based on histopathological findings and organ damage, SM is divided into indolent SM (ISM), smoldering SM (SSM), SM with an associated hematologic non-MC-lineage disease (SM-AHNMD), aggressive SM (ASM), and MC leukemia (MCL). The clinical course and prognosis vary greatly among these groups of patients. In all variants of SM and most patients, neoplastic cells display the KIT mutation D816V. This suggests that additional KIT-independent molecular defects cause progression. Indeed, additional oncogenic lesions, including RAS- and TET2 mutations, have recently been identified in advanced SM. In patients with SM-AHNMD, such additional lesions are often detectable in the ‘AHNMD-component’ of the disease. Clinically relevant symptoms of SM result from i) malignant MC infiltration and the subsequent organ damage seen in advanced SM and/or ii) the release of pro-inflammatory and vasoactive mediators from MC, found in all disease-variants. Therapy of SM has to be adjusted to the individual situation in each patient. In ISM, the aim is to control mediator release and mediator effects. In advanced SM, a major goal is to control MC expansion by using conventional drugs or novel targeted drugs directed against mutant forms of KIT and/or other pro-oncogenic kinase-targets. In rapidly progressing ASM, MCL and drug-resistant AHNMD, chemotherapy and subsequent stem cell transplantation has to be considered. PMID:23593539

  9. Synthesis of mixed-ligand complexes of rare-earth elements

    SciTech Connect

    Panyushkin, V.T.; Akhrimenko, N.V.

    1994-09-10

    The authors have synthesized mixed-ligand complexes of Nd(III), Sm(III), Eu(III), Tb(III), Dy(III), Ho(III), Er(III), and Yb(III) with acetylacetone (I) and unsaturated organic acids (II): maleic, fumaric, acrylic, and methacrylic. According to elemental analyses and thermogravimetric data the composition of Ln(I){sub 2}(II) {center_dot} 3H{sub 2}O does not depend on the basicity of the acid. The structure of compounds prepared was studied by IR, NMR, and luminescent spectroscopy.

  10. Rare earth mineralisation in the Cnoc nan Cuilean intrusion of the Loch Loyal Syenite Complex, northern Scotland

    NASA Astrophysics Data System (ADS)

    Walters, A. S.; Hughes, H. S. R.; Goodenough, K. M.; Gunn, A. G.; Lacinska, A.

    2012-04-01

    Due to growing global concerns about security of rare earth element (REE) supply, there is considerable interest in identifying new deposits and in understanding the processes responsible for their formation. Ongoing studies by BGS on potential indigenous resources have focused on the Caledonian alkaline intrusive complexes of north-west Scotland. The highest values of total rare earth oxide (TREO) have been found in the Cnoc nan Cuilean intrusion of the Loch Loyal Complex in Sutherland. The Loch Loyal Syenite Complex comprises three intrusions: Ben Loyal, Beinn Stumanadh and Cnoc nan Cuilean. The Cnoc nan Cuilean intrusion, which covers an area of about 3 km2, can be subdivided into two zones: a Mixed Syenite Zone (MSZ) and a later Massive Leucosyenite Zone (MLZ). Evidence from field mapping and 3D-modelling suggests that the melasyenites were passively emplaced to form a lopolith concordant with the Moine and Lewisian country rocks. A later episode of leucosyenitic magmatism caused mixing and mingling with the melasyenite forming the MSZ. Continued intrusion of leucosyenite melts then formed the MLZ [1]. The melasyenites are enriched in TREO relative to the leucosyenites with average values of 3800 ppm and 1400 ppm respectively. The highest contents, up to 20 000 ppm TREO, are found in narrow biotite-magnetite-rich veins identified in a single stream section near the eastern margin of the intrusion. All lithologies are light rare earth element (LREE) dominated with high concentrations of Ba and Sr and low levels of Nb and Ta. Various REE-bearing minerals are present but allanite is dominant, being present in all major magmatic lithologies and the biotite-magnetite veins. Three generations of allanite have been identified: a late-magmatic phase rimming apatite; allanite micro veinlets cross-cutting the syenite; and a third phase only observed in the biotite-magnetite veins. TREO concentrations of the different allanite generations are similar, averaging 22%. The

  11. Synthesis, structure, and spectroscopic and magnetic properties of mesomorphic octakis(hexylthio)-substituted phthalocyanine rare-earth metal sandwich complexes.

    PubMed

    Gürek, Ayse Gül; Basova, Tamara; Luneau, Dominique; Lebrun, Colette; Kol'tsov, Evgeny; Hassan, Aseel K; Ahsen, Vefa

    2006-02-20

    The syntheses of new bis[octakis(hexylthio)phthalocyaninato] rare-earth metal(III) double-decker complexes [(C6S)8-Pc]2M (M = Gd(III), Dy(III), and Sm(III)) (2-4, respectively) are described. These compounds are very soluble in most common organic solvents. They have been fully characterized using elemental analysis, infrared, UV-vis spectroscopy, and mass spectrometry. The crystal structures of compounds 2-4 have been determined by X-ray diffraction on a single crystal. They are isostructural and crystallize in the monoclinic space group (space group C2/c). Their lattice constants have been determined in the following order: (2) a = 31.629(4) Angstroms, b = 32.861(4) Angstroms, c = 20.482(2) Angstroms, beta = 126.922(2) degrees, V = 17019(3) Angstroms(3); (3) a = 31.595(2) Angstroms, b = 32.816(2) Angstroms, c = 20.481(1) Angstroms, beta = 127.005(1) degrees, V = 16958(2) Angstroms(3); (4) a = 31.563(2) Angstroms, b = 32.796(2) Angstroms, c = 20.481(1) Angstroms, beta = 127.032 degrees, V = 16924(2) Angstroms(3). The magnetic properties of compounds 2-4 were studied, and it was revealed that the lanthanide ions and the radical delocalized on the two phthalocyanine rings are weakly interacting. The mesogenic properties of these new materials were studied by differential scanning calorimetry and optical microscopy. These phthalocyanine derivatives form columnar-hexagonal (Col(h)) mesophases. Thin films of bis[octakis(hexylthio)phthalocyaninato] rare-earth metal(III) double-decker complexes (2-4) were prepared by a spin-coating technique. Thermally induced molecular reorganization within films of bis[octakis(hexylthio)phthalocyaninato] rare-earth metal(III) double-decker complexes (2-4) was studied by the methods of ellipsometry, UV-vis absorption spectroscopy, and atomic force microscopy. Heat treatment produces molecular ordering, which is believed to be due to stacking interaction between neighboring phthalocyanine moieties. PMID:16471979

  12. Bézier curve string method for the study of rare events in complex chemical systems

    NASA Astrophysics Data System (ADS)

    Bellucci, Michael A.; Trout, Bernhardt L.

    2014-08-01

    We present a new string method for finding the most probable transition pathway and optimal reaction coordinate in complex chemical systems. Our approach evolves an analytic parametric curve, known as a Bézier curve, to the most probable transition path between metastable regions in configuration space. In addition, we demonstrate that the geometric properties of the Bézier curve can be used to construct the optimal reaction coordinate near the most probable reaction path, and can further be used to devise a ranking vector capable of identifying precisely which collective variables are most important for governing the transition between metastable states. We discuss the algorithmic details of the Bézier curve string method, analyze its stability, accuracy and efficiency, and illustrate its capabilities using model potential energy functions. In particular, we use the degree elevation property of Bézier curves to develop an algorithm that adaptively learns the degree polynomial necessary to accurately represent the most probable transition path. Subsequently, we apply our method to the isomerization of alanine dipeptide, and demonstrate that the reaction coordinate obtained from the Bézier curve string method is in excellent agreement with the optimal reaction coordinate constructed from an aimless shooting and maximum likelihood procedure. Finally, we apply our method to a large complex system and study the homogenous nucleation of benzene from the melt. In these two examples, we illustrate that the ranking vector correctly identifies which collective variables govern these chemical transitions.

  13. The Early Jurassic Bokan Mountain peralkaline granitic complex (southeastern Alaska): geochemistry, petrogenesis and rare-metal mineralization

    USGS Publications Warehouse

    Dostal, Jaroslav; Kontak, Daniel J.; Karl, Susan M.

    2014-01-01

    The Early Jurassic (ca. 177 Ma) Bokan Mountain granitic complex, located on southern Prince of Wales Island, southernmost Alaska, cross-cuts Paleozoic igneous and metasedimentary rocks of the Alexander terrane of the North American Cordillera and was emplaced during a rifting event. The complex is a circular body (~3 km in diameter) of peralkaline granitic composition that has a core of arfvedsonite granite surrounded by aegirine granite. All the rock-forming minerals typically record a two-stage growth history and aegirine and arfvedsonite were the last major phases to crystalize from the magma. The Bokan granites and related dikes have SiO2 from 72 to 78 wt. %, high iron (FeO (tot) ~3-4.5 wt. %) and alkali (8-10 wt.%) concentrations with high FeO(tot)/(FeO(tot)+MgO) ratios (typically >0.95) and the molar Al2O3/(Na2O+K2O) ratio Nd values which are indicative of a mantle signature. The parent magma is inferred to be derived from an earlier metasomatized lithospheric mantle by low degrees of partial melting and generated the Bokan granitic melt through extensive fractional crystallization. The Bokan complex hosts significant rare-metal (REE, Y, U, Th, Nb) mineralization that is related to the late-stage crystallization history of the complex which involved the overlap of emplacement of felsic dikes, including pegmatite bodies, and generation of orthomagmatic fluids. The abundances of REE, HFSE, U and Th as well as Pb and Nd isotopic values of the pluton and dikes were modified by orthomagmatic hydrothermal fluids highly enriched in the strongly incompatible trace elements, which also escaped along zones of structural weakness to generate rare-metal mineralization. The latter was deposited in two stages: the first relates to the latest stage of magma emplacement and is associated with felsic dikes that intruded along the faults and shear deformations, whereas the second stage involved ingress of hydrothermal fluids that both remobilized and enriched the initial

  14. Deposition of rare-earth phosphate, fluoride, and oxysulfide films by gas-phase thermolysis of {beta}-diketonate complexes

    SciTech Connect

    Gorshkov, N.I.; Suglobov, D.N.; Sidorenko, G.V.

    1995-07-01

    Rare-earth fluoride, phosphate, and oxysulfide films have been obtained by gas-phase thermolysis of appropriate rare-earth mixed-ligand and tris-chelate {beta}-diketonate complexes. Gas-phase thermolysis of Ln(PTFA){sub 3} {center_dot}HMPA and Ln(HFA){sub 3}{center_dot}2HMPA (PTFA is pivaloyltrifluoroacetonate ligand and HFA is hexafluoracetylacetonate ligand, HMPA is hexamethylphosphoric triamide, Ln = Nd, Eu, Er) in a flow of air or N{sub 2}O yields a finely dispersed phosphate phase. Thermolysis of Ln(HFA){sub 3} {center_dot}DME (Ln = Nd, Eu, Er, DME is 1,2-dimethoxyethane) yields carbon-free fluoride films, whereas in the case of Er(HFA){sub 3}{center_dot}2H{sub 2}O and Er(PTFA){sub 3} erbium oxyfluoride and oxide films are deposited. Thermolysis of Nd(DPM){sub 3} (DPM is dipivaloylmethanate ligand) in hydrogen sulfide flow yields and Nd{sub 2}O{sub 2}S phase.

  15. Infra-red spectroscopic characteristics of naphthalocyanine in bis(naphthalocyaninato) rare earth complexes peripherally substituted with thiophenyl derivatives

    NASA Astrophysics Data System (ADS)

    Li, Xiaobo; Mao, Yajun; Xiao, Chi; Lu, Fanli

    2015-04-01

    The infra-red (IR) spectroscopic data for a series of eleven rare earth double-deckers MIII[Nc(SPh)8]2 (M = Y, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Er) have been collected and systematically investigated. For MIII[Nc(SPh)8]2, typical IR marker bands for the naphthalocyanine anion radical [Nc(SPh)8]rad - were observed at 1317-1325 cm-1 as the most intense absorption bands, which can be attributed to the pyrrole stretching. As for Ce[Nc(SPh)8]2, the typical IR marker band was also observed at 1317 cm-1, which shows that the cerium complex exists as the form of CeIII[Nc(SPh)8]2-[Nc(SPh)8]rad -. In addition, both the Q-bands of electronic absorption spectra and the typical IR absorption bands of naphthalocyanine radical anion [Nc(SPh)8]rad - move to the high energy as the decrease of rare earth metal ionic radius. These facts suggest that the π-π electron interaction in these double-deckers becomes stronger along with the lanthanide contraction.

  16. Admixture and the organization of genetic diversity in a butterfly species complex revealed through common and rare genetic variants.

    PubMed

    Gompert, Zachariah; Lucas, Lauren K; Buerkle, C Alex; Forister, Matthew L; Fordyce, James A; Nice, Chris C

    2014-09-01

    Detailed information about the geographic distribution of genetic and genomic variation is necessary to better understand the organization and structure of biological diversity. In particular, spatial isolation within species and hybridization between them can blur species boundaries and create evolutionary relationships that are inconsistent with a strictly bifurcating tree model. Here, we analyse genome-wide DNA sequence and genetic ancestry variation in Lycaeides butterflies to quantify the effects of admixture and spatial isolation on how biological diversity is organized in this group. We document geographically widespread and pervasive historical admixture, with more restricted recent hybridization. This includes evidence supporting previously known and unknown instances of admixture. The genome composition of admixed individuals varies much more among than within populations, and tree- and genetic ancestry-based analyses indicate that multiple distinct admixed lineages or populations exist. We find that most genetic variants in Lycaeides are rare (minor allele frequency <0.5%). Because the spatial and taxonomic distributions of alleles reflect demographic and selective processes since mutation, rare alleles, which are presumably younger than common alleles, were spatially and taxonomically restricted compared with common variants. Thus, we show patterns of genetic variation in this group are multifaceted, and we argue that this complexity challenges simplistic notions concerning the organization of biological diversity into discrete, easily delineated and hierarchically structured entities. PMID:24866941

  17. Photoacoustic spectroscopy study on the co-luminescence phenomena of solid rare earth complexes

    SciTech Connect

    Yang Yuetao . E-mail: yyang@nju.edu.cn; Zhang Shuyi; Su Qingde

    2005-06-15

    Photoacoustic (PA) spectra of coprecipitates Tb{sup 3+}-Ln{sup 3+}-Sal complexes are reported (Sal: salicylic acid; Ln{sup 3+}:Gd{sup 3+} or Nd{sup 3+}). For Tb{sup 3+}-Gd{sup 3+}-Sal coprecipitates, the PA intensity in the region of ligand absorption decreases firstly with increasing the concentration of Gd{sup 3+}, and then increases. For Tb{sup 3+}-Nd{sup 3+}-Sal coprecipitates, the PA intensity of the ligand increases remarkably. The difference in PA intensities is interpreted in terms of probability of nonradiative transitions. The changes of luminescence spectra turn out to be complementary to the PA spectra. Combined with PA phase shifts, which are directly related to the relaxation processes, the luminescence enhancement and quenching phenomena of the coprecipitates are discussed by two aspects: radiative and nonradiative processes.

  18. Rare earth organic complexes as down-shifters to improve Si-based solar cell efficiency

    NASA Astrophysics Data System (ADS)

    Le Donne, A.; Dilda, M.; Crippa, M.; Acciarri, M.; Binetti, S.

    2011-05-01

    This work reports on the optical and electrical characterization of crystalline silicon based solar modules encapsulated with ethylene-vinyl-acetate layers (that is the encapsulating matrix used nowadays by the photovoltaic industry) doped with a single europium complex whose sensitized region is broadened due to the presence of a co-ligand. Such europium doped EVA layers are able to realize down-shifting of photons with wavelength lower than 460 nm without introducing modifications of the industrial process leading to the fabrication of the photovoltaic modules. This effect has been proven under Air Mass 1.5 conditions (simulating terrestrial applications), where a 2.9% relative increase of the total power delivered by the encapsulated modules has been observed, allowing a reduction in the watt-peak price.

  19. Green exciplex emission from a bilayer light-emitting diode containing a rare earth ternary complex

    NASA Astrophysics Data System (ADS)

    Gao, De-Qing; Huang, Yan-Yi; Huang, Chun-Hui; Li, Fu-You; Huang, Ling

    2001-12-01

    A bilayer organic light-emitting diode using a blue-fluorescent yttrium complex, tris(1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone)-(2,2 '-dipyridyl) yttrium [Y(PMIP) 3(Bipy)] (YPB) as an emitting material and poly( N-vinylcarbazole) (PVK) as a hole-transporting material emitted bright green light instead of blue light. It was attributed to the exciplex formation at the solid interface between the PVK and YPB layers, which was demonstrated by the measurement of the absorption, photoluminescence (PL) and photoluminescence excitation (PLE) spectra of the mixture of PVK and YPB (molar ratio 1:1). The device exhibited a maximum luminance of 177 cd/m 2 and a peak power efficiency of 0.02 lm/W.

  20. Association of hypothyroid disease in Doberman Pinscher dogs with a rare major histocompatibility complex DLA class II haplotype.

    PubMed

    Kennedy, L J; Huson, H J; Leonard, J; Angles, J M; Fox, L E; Wojciechowski, J W; Yuncker, C; Happ, G M

    2006-01-01

    Canine hypothyroid disease is similar to Hashimoto's disease in humans, which has been shown to be associated with human major histocompatibility complex (MHC) genes. We have collected 27 Doberman Pinschers affected with primary hypothyroid disease and compared their MHC class II haplotypes with 129 unaffected Doberman Pinschers. Three dog-leucocyte antigen (DLA) genes, DLA-DRB1, DQA1 and DQB1, were characterized by sequence-based typing and assigned to haplotypes for each dog. One rare haplotype was found at an increased frequency in the affected dogs compared to the unaffected dogs (Odds ratio = 2.43, P < 0.02). This haplotype has only been found in Doberman Pinschers and Labradors to date. PMID:16451201

  1. The Early Jurassic Bokan Mountain peralkaline granitic complex (southeastern Alaska): Geochemistry, petrogenesis and rare-metal mineralization

    NASA Astrophysics Data System (ADS)

    Dostal, Jaroslav; Kontak, Daniel J.; Karl, Susan M.

    2014-08-01

    The Early Jurassic (ca. 177 Ma) Bokan Mountain granitic complex, located on southern Prince of Wales Island, southernmost Alaska, cross-cuts Paleozoic igneous and metasedimentary rocks of the Alexander terrane of the North American Cordillera and was emplaced during a rifting event. The complex is a circular body (~ 3 km in diameter) of peralkaline granitic composition that has a core of arfvedsonite granite surrounded by aegirine granite. All the rock-forming minerals typically record a two-stage growth history and aegirine and arfvedsonite were the last major phases to crystallize from the magma. The Bokan granites and related dikes have SiO2 from 72 to 78 wt.%, high iron (FeO (tot) ~ 3-4.5 wt.%) and alkali (8-10 wt.%) concentrations with high FeO(tot)/(FeO(tot) + MgO) ratios (typically > 0.95) and the molar Al2O3/(Na2O + K2O) ratio < 1. The granitic rocks are characterized by elevated contents of rare earth elements (REE), Th, U and high field strength elements (HFSE) and low contents of Ca, Sr, Ba and Eu, typical of peralkaline granites. The granites have high positive εNd values which are indicative of a mantle signature. The parent magma is inferred to be derived from an earlier metasomatized lithospheric mantle by low degrees of partial melting and generated the Bokan granitic melt through extensive fractional crystallization. The Bokan complex hosts significant rare-metal (REE, Y, U, Th, Nb) mineralization that is related to the late-stage crystallization history of the complex which involved the overlap of emplacement of felsic dikes, including pegmatite bodies, and generation of orthomagmatic fluids. The abundances of REE, HFSE, U and Th as well as Pb and Nd isotopic values of the pluton and dikes were modified by orthomagmatic hydrothermal fluids highly enriched in the strongly incompatible trace elements, which also escaped along zones of structural weakness to generate rare-metal mineralization. The latter was deposited in two stages: the first

  2. Microwave and ab initio studies of rare gas-methane van der Waals complexes

    NASA Astrophysics Data System (ADS)

    Liu, Yaqian; Jäger, Wolfgang

    2004-05-01

    Rotational spectra of the weakly bound Kr-methane van der Waals complex were recorded using a pulsed molecular beam Fourier transform microwave spectrometer in the range from 3.5 to 18 GHz. Spectra of 25 isotopomers of Kr-methane were assigned and analyzed. For isotopomers containing CH4, 13CH4, and CD4, two sets of transitions with K=0 and one with K=1 were recorded, correlating to the j=0, 1, and 2 rotational levels of free methane, respectively (j is the rotational angular momentum quantum number of the methane monomer). For isotopomers containing CH3D and CHD3, two K=0 components were recorded, correlating to the jk=00 and 11 rotational levels of free methane (k corresponds to the projection of j onto the C3 axis of CH3D and CHD3). The obtained spectroscopic results were used to derive van der Waals bond distance R, van der Waals stretching frequency νs, and the corresponding stretching force constant ks. Nuclear spin statistical weights of individual states were obtained from molecular symmetry group analyses and were compared with the observed relative transition intensities. The tentatively assigned j=2 transitions were more intense than predicted from symmetry considerations. This is attributed to a relatively large effective dipole moment of this state, supported by ab initio dipole moment calculations. Ab initio potential energy calculations of Kr-CH4 and Ar-CH4 were done at the coupled cluster level of theory, with single and double excitations and perturbative inclusion of triple excitations, using the aug-cc-pVTZ basis set supplemented with bond functions. The theoretical results show that the angular dynamics of the dimer does not change significantly when the binding partner of methane changes from Ar to Kr. The dipole moment of Ar-CH4 was calculated at various configurations, providing a qualitative explanation for the unsuccessful spectral searches for rotational transitions of Ar-CH4.

  3. Strategies for the transfusion of subjects with complex red cell immunisation: the Bank of rare blood donors of the Region of Lombardy

    PubMed Central

    Morelati, Fernanda; Arnaboldi, Piera; Barocci, Fiorella; Bodini, Umberto; Boiani, Elisa; Bresciani, Susanna; Cambiè, Giuseppe; Cazzaniga, Giovanni; Cocco, Ernesto; Copeta, Alessandro; Crotti, Massimo; D’Agostino, Francesco; D’Agostino, Marco; Focchiatti, Valeria; Fonti, Elena; Galassi, Luigi; Gazzola, Giambattista; Gelpi, Luigi; Greppi, Noemi; Inghilleri, Giovanni Battista; Isernia, Paola; Manera, Maria Cristina; Marini, Mirella; Monti, Rosalia; Morales, Rino; Moroni, Gianalessandro; Morra, Enrica; Pau, Maria Paola; Paccapelo, Cinzia; Pagliaro, Pasqualepaolo; Prati, Daniele; Revelli, Nicoletta; Rinaldini, Claudia; Rossi, Davide; Rossi, Fabio; Salvaneschi, Laura; Sciariada, Luca; Sergiacomo, Pierluigi; Tiburzi, Alessandra; Trotti, Roberta; Turdo, Rosalia; Velati, Claudio; Villa, Maria Antonietta; Vismara, Giuseppina; Vitali, Elisabetta; Marconi, Maurizio

    2007-01-01

    Introduction Selecting units of rare blood for transfusion to patients with complex immunisation is one of the most critical processes of a Transfusion Centre. In January 2005 the ‘Rare Blood Components Bank – Reference Centre of the Region of Lombardy’ w as established with the following goals: 1) identifying regional rare blood donors; 2) creating a regional registry of rare donors; 3) organising a regional bank of liquid and frozen rare blood units; 4) setting up a regional Immunohaematology Reference Laboratory (IRL) to type donors and resolve complex cases. Methods The key elements in establishing the Bank were periodic meetings organised by the directors and representatives of the regional Departments of Transfusion Medicine and Haematology (DTMH) and the institution of three working groups (informatics, regulations, finance). Results The regional IRL was set up, the relevant operating procedures were distributed region-wide, software features were defined and later validated upon activation, and the funds assigned were allocated to various cost items. The number and characteristics of the donors to be typed were identified and 14 regional DTMHs started to send samples. Overall, 20,714 donors were typed, for a total of 258,003 typings, and 2,880 rare donors were identified. Of these, 97% were rare donors because of combinations of antigens (2,139 negative for the S antigen and 659 negative for the s antigen) and 3% (n=82) because they were negative for high-frequency antigens. In the first 2 years of activity, the IRL carried out investigations of 140 complex cases referred from other Centres and distributed 2,024 units with rare phenotypes to 142 patients. Conclusions The main goal achieved in the first 24 months from the start of the project was to set up a regional network able to meet the transfusion needs of patients with complex immunisation. PMID:19204778

  4. Investigation of organic magnetoresistance dependence on spin-orbit coupling using 8-hydroxyquinolinate rare-earth based complexes

    NASA Astrophysics Data System (ADS)

    Carvalho, R. S.; Costa, D. G.; Ávila, H. C.; Paolini, T. B.; Brito, H. F.; Capaz, Rodrigo B.; Cremona, M.

    2016-05-01

    The recently discovered organic magnetoresistance effect (OMAR) reveals the spin-dependent behavior of the charge transport in organic semiconductors. So far, it is known that hyperfine interactions play an important role in this phenomenon and also that spin-orbit coupling is negligible for light-atom based compounds. However, in the presence of heavy atoms, spin-orbit interactions should play an important role in OMAR. It is known that these interactions are responsible for singlet and triplet states mixing via intersystem crossing and the change of spin-charge relaxation time in the charge mobility process. In this work, we report a dramatic change in the OMAR effect caused by the presence of strong intramolecular spin-orbit coupling in a series of rare-earth quinolate organic complex-based devices. Our data show a different OMAR lineshape compared with the OMAR lineshape of tris(8-hydroxyquinolinate) aluminum-based devices, which are well described in the literature. In addition, electronic structure calculations based on density functional theory help to establish the connection between this results and the presence of heavy central ions in the different complexes.

  5. Two types of rare earth-organic frameworks constructed by racemic tartaric acid

    SciTech Connect

    Jiang Zhanguo; Lv Yaokang; Cheng Jianwen; Feng Yunlong

    2012-01-15

    Hydrothermal reactions of rare earth oxides with racemic tartaric acid (H{sub 2}tar) yielded 7 rare earth(III) MOFs with general formulas [R{sub 2}(tar){sub 3}(H{sub 2}O){sub 2}]{sub n} (R=Y (1), Sm (4), Eu (5), Tb (6), Dy (7)) and [R{sub 2}(tar){sub 2}(C{sub 2}O{sub 4})(H{sub 2}O){sub 2}]{sub n}{center_dot}4nH{sub 2}O (R=La (2), Nd (3)). X-ray powder diffraction analysis and single-crystal X-ray diffraction analysis reveal that they present two different structural types. MOFs 1, 4, 5, 6 and 7 are isostructural and crystallize in the orthorhombic non-centrosymmetric space group Iba2, and feature unusual fsc-3,4-Iba2 topology. MOFs 2 and 3 are isostructural and crystallize in monoclinic P2{sub 1}/c space group and display rare fsx-4,5-P2{sub 1}/c topology containing hydrophilic channels bounded by triple helical chains along a axis. MOFs 3, 4, 5, 6 and 7 exhibit intense lanthanide characteristic photoluminescence at room temperature. - Graphical Abstract: [R{sub 2}(tar){sub 2}(C{sub 2}O{sub 4})(H{sub 2}O){sub 2}]{sub n}{center_dot}4nH{sub 2}O (R=La (2), Nd (3)) display rare fsx-4,5-P2{sub 1}/c topology containing hydrophilic channels bounded by triple helical chains along a axis. Highlights: Black-Right-Pointing-Pointer Two types of rare earth MOFs were synthesized by hydrothermal conditions. Black-Right-Pointing-Pointer MOFs feature unusual fsc-3,4-Iba2 and rare fsx-4,5-P2{sub 1}/c topology structures. Black-Right-Pointing-Pointer MOFs exhibit intense lanthanide characteristic photoluminescence.

  6. Evaluation of AA5052 alloy anode in alkaline electrolyte with organic rare-earth complex additives for aluminium-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, Dapeng; Li, Heshun; Liu, Jie; Zhang, Daquan; Gao, Lixin; Tong, Lin

    2015-10-01

    Behaviours of the AA5052 aluminium alloy anode of the alkaline aluminium-air battery are studied by the hydrogen evolution test, the electrochemical measurements and the surface analysis method. The combination of amino-acid and rare earth as electrolyte additives effectively retards the self-corrosion of AA5052 aluminium alloy in 4 M NaOH solution. It shows that the combination of L-cysteine and cerium nitrate has a synergistic effect owing to the formation of a complex film on AA5052 alloy surface. The organic rare-earth complex can decrease the anodic polarisation, suppress the hydrogen evolution and increase the anodic utilization rate.

  7. A series of lanthanoid selenidoantimonates(V): rare examples of lanthanoid selenidoantimonates based on dinuclear lanthanide complexes.

    PubMed

    Xiao, Hong-Ping; Zhou, Jian; Zhao, Rong-Qing; Zhang, Wei-bing; Huang, Yong

    2015-04-01

    A series of new lanthanoid selenidoantimonates(V) [Ln(en)(tepa)SbSe4] (Ln = La (Ia), Ce (Ib), Pr (Ic); en = ethylenediamine, tepa = tetraethylenepentamine) and [Ln2(tepa)2(μ-OH)2Cl2]-{[Ln(tepa)]2(μ-OH)2(SbSe4)2} (Ln = Y (IIa), Sm (IIb), Gd (IIc), Tb (IId), Dy (IIe), and Tm (IIf)) were solvothermally synthesized and structurally characterized. The structures of Ia-c consist of neutral molecules [Ln(en)(tepa)SbSe4], where the tetrahedral [SbSe4](3-) anion acts as a ligand to chelate the [Ln(en)(tepa)](3+) cation. The structures of IIa-f contain isolated dinuclear [Ln2(tepa)2(μ-OH)2Cl2](2+) cations built up from two [Ln(tepa)Cl](2+) ions linked by two -OH bridging groups and organic decorated {[Ln(tepa)]2(μ-OH)2(SbSe4)2}(2-) anions based on two [Ln(tepa)SbSe4] units bridged by two -OH groups. Although a few lanthanoid selenidoantimonates(V) under solvothermal conditions have been reported, their lanthanide complexes normally appear mononuclear. Hence, IIa-f are rare examples of lanthanoid selenidoantimonates based on dinuclear lanthanide complexes. A preliminary investigation of nine lanthanoid selenidoantimonates(V) shows that the well-known lanthanide contraction has a significant influence on the formation of lanthanoid selenidoantimonates(V) under solvothermal conditions. The absorption edges of all compounds have been investigated by UV-vis spectroscopy, and density functional theory calculations for Ia and IIc have also been performed. PMID:25723709

  8. Enhanced optical limiting effects in a double-decker bis(phthalocyaninato) rare earth complex using radially polarized beams

    SciTech Connect

    Wu, Jia-Lu; Gu, Bing Liu, Dahui; Cui, Yiping; Sheng, Ning

    2014-10-27

    Optical limiting (OL) effects can be enhanced by exploiting various limiting mechanisms and by designing nonlinear optical materials. In this work, we present the large enhancement of OL effects by manipulating the polarization distribution of the light field. Theoretically, we develop the Z-scan and nonlinear transmission theories on a two-photon absorber under the excitation of cylindrical vector beams. It is shown that both the sensitivity of Z-scan technique and the OL effect using radially polarized beams have the large enhancement compared with that using linearly polarized beams (LPBs). Experimentally, we investigate the nonlinear absorption properties of a double-decker Pr[Pc(OC{sub 8}H{sub 17}){sub 8}]{sub 2} rare earth complex by performing Z-scan measurements with femtosecond-pulsed radially polarized beams at 800 nm wavelength. The observed two-photon absorption process, which originates from strong intramolecular π–π interaction, is exploited for OL application. The results demonstrate the large enhancement of OL effects using radially polarized beams instead of LPBs.

  9. A Novel Adaptive Method for the Analysis of Next-Generation Sequencing Data to Detect Complex Trait Associations with Rare Variants Due to Gene Main Effects and Interactions

    PubMed Central

    Liu, Dajiang J.; Leal, Suzanne M.

    2010-01-01

    There is solid evidence that rare variants contribute to complex disease etiology. Next-generation sequencing technologies make it possible to uncover rare variants within candidate genes, exomes, and genomes. Working in a novel framework, the kernel-based adaptive cluster (KBAC) was developed to perform powerful gene/locus based rare variant association testing. The KBAC combines variant classification and association testing in a coherent framework. Covariates can also be incorporated in the analysis to control for potential confounders including age, sex, and population substructure. To evaluate the power of KBAC: 1) variant data was simulated using rigorous population genetic models for both Europeans and Africans, with parameters estimated from sequence data, and 2) phenotypes were generated using models motivated by complex diseases including breast cancer and Hirschsprung's disease. It is demonstrated that the KBAC has superior power compared to other rare variant analysis methods, such as the combined multivariate and collapsing and weight sum statistic. In the presence of variant misclassification and gene interaction, association testing using KBAC is particularly advantageous. The KBAC method was also applied to test for associations, using sequence data from the Dallas Heart Study, between energy metabolism traits and rare variants in ANGPTL 3,4,5 and 6 genes. A number of novel associations were identified, including the associations of high density lipoprotein and very low density lipoprotein with ANGPTL4. The KBAC method is implemented in a user-friendly R package. PMID:20976247

  10. Barium silicates of the Berisal Complex, Switzerland: A study in geochronology and rare-gas release systematics

    NASA Astrophysics Data System (ADS)

    Hetherington, C. J.; Villa, I. M.

    2007-07-01

    Barium silicate minerals such as celsian, ganterite, armenite, as well as Ba-bearing and Ba-free white mica from the Berisal Complex, Simplon Nappe, Swiss Alps, were dated by 39Ar- 40Ar. Ages of Ba-free micas are ca. 17 Ma, while Ba and parentless 40Ar are correlated in Ba silicates, suggesting common inheritance from the Paleozoic orthogneissic protolith. The release pattern of reactor-produced 39Ar (or 37Ar) from hydrated and anhydrous minerals is very similar, with apparent activation energies of ca. 180 kJ/mole and a conspicuous kink around 900 °C. White micas release Ar at higher temperature than the literature determination of their dehydroxylation. In addition to Ar, we studied the degassing of monoisotopic 131Xe produced from Ba during neutron irradiation. Xe is degassed at higher temperature than Ar, and again all analyzed silicates have the same apparent activation energy of ca. 300 kJ/mole. The decoupling of Ar and Xe rules out delamination as the dominant degassing mechanism in mica and implies that recoiled rare gas atoms mostly reside inside the T-O-T layers of the mica structure. The near-identical apparent activation energies in such diverse silicates as tecto-, phyllo- and cyclosilicate requires instead that the in-vacuo gas release kinetics are the same in all three silicates. As the only structural element common to these three silicate families are silica tetrahedra, it is possible that their well-known rotation plays a decisive role for in-vacuo Ar degassing; additional high-temperature in situ structural investigations on feldspars and micas would be needed to help constrain the mechanisms of laboratory Ar release.

  11. Intermolecular dispersion interactions of normal alkanes with rare gas atoms: van der Waals complexes of n-pentane with helium, neon, and argon

    NASA Astrophysics Data System (ADS)

    Balabin, Roman M.

    2008-09-01

    Interaction energies of normal pentane with three rare gas atoms (helium, neon, and argon) were calculated using ab initio methods: the second-order Møller-Plesset (MP2), the fourth-order Møller-Plesset (MP4), and coupled cluster with single and double substitutions with noniterative triple excitation (CCSD(T)) levels of theory. Dunning's correlation consistent basis sets up to aug-cc-pVQZ were applied. Eight profiles (246 points for each rare gas atom) of potential energy surface (PES) of all-trans (anti-anti) conformation of n-pentane were scanned. Optimal distances for complex formation were found. MP2 interaction energies at the basis set limit were evaluated by three different methods (Feller's, Helgaker's, and Martin's). The MP2 interaction energy at the basis set limit for a global minimum of n-pentane complex with argon was more than 400 cm -1, so formation of a stable complex (at least at low temperature) can be expected. A comparison with previously published data on propane complexes with rare gas atoms (both computational and experimental) was done. The MP4 level of theory was found to be sufficient for a description of C 5H 12 complexes with helium, neon, and argon.

  12. A study of the complex formation of some rare-earth elements with 1,2,3-benzotriazole and 3-amino-1,2,4-triazole

    SciTech Connect

    Akhrimenko, Z.M.; Panyushkin, V.T.; Akhrimenko, N.V.; Atamanchuk, T.A.

    1994-01-01

    Complex compounds of a number of rare-earth chlorides with 1,2,3-benzotriazole (L{sup 1}) and 3-amino-1,2,4-triazole (L{sup 2}) of compositions LnCl{sub 3}{center_dot}3L{sup 1} (Ln=La, Pr, Nd, Sm, Eu, and Gd) and LnCl{sub 3}{center_dot}L{sup 2}{center_dot}2H{sub 2}O{center_dot}2EtOH (Ln=La, Pr, Nd, Sm, Gd, Tb, Ho, Er, Yb, and Lu) were synthesized, and their IR spectra (4000 - 200 cm{sup {minus}1}) were examined. It is established that the complexes of rare-earth elements with L{sup 1} are more stable in comparison with the complexes with L{sup 2}.

  13. Petrogenesis of orbicular ijolites from the Prairie Lake complex, Marathon, Ontario: Textural evidence from rare processes of carbonatitic magmatism

    NASA Astrophysics Data System (ADS)

    Zurevinski, Shannon E.; Mitchell, Roger H.

    2015-12-01

    A unique occurrence of orbicular ijolite is hosted in a matrix of contemporaneous holocrystalline ijolite at the 1.1 Ga Prairie Lake Carbonatite Complex (Marathon, Ontario, Canada), and is the only known occurrence of this textural type in a rock of ijolitic composition. This mineralogical and petrological study of this orbicular ijolite highlights many of the differences from other rare occurrences of orbicular rocks described from carbonatites, granites, diorites and lamprophyres. The orbicules occur along distinct, densely packed bands in equigranular nepheline-rich ijolite and range up to 6 cm in diameter. Macroscopically, the orbicules show variability in the mineralogy of their cores. Detailed imaging of the cores shows evidence of quench textures. Radial outward zoning is common near the cores with concentric banding occurring toward the margins of the orbicules. The mineralogy of the orbicules consists of: nepheline; diopside; calcite; apatite; andradite-melanite garnet; titanite; Fe-rich phlogopite; titaniferous magnetite; perovskite; with secondary natrolite, calcite and cancrinite. The mineralogy of the host ijolite is similar to that of the orbicules. Mineral compositions from the orbicular ijolite and the host ijolite are similar. Within the orbicules, anhedral minerals are found occurring in a 'matrix' of garnet throughout the distinct concentric bands. The textures within the concentric bands of the orbicules are best described as annealing recrystallization textures. The rims of the orbicules form interlocking crystals with the host ijolite resulting in near-indistinguishable boundaries. The orbicules are interpreted to represent interaction of a partially-crystallized quenched ijolitic melt, which was in contact with a second pulse of consanguineous ijolite magma. Immersion in the latter resulted in sub-solidus diffusion and annealing recrystallization. Orbicular textures were produced from previously formed quenched ijolite, which was

  14. Influence of inner-sphere processes on the paramagnetic shifts in the {sup 1}H NMR spectra of some mixed-ligand complexes of rare-earth elements

    SciTech Connect

    Khachatryan, A.S.; Vashchuk, A.V.; Panyushkin, V.T.

    1995-12-20

    Concentration dependences of the observed chemical shifts in the NMR spectra of 1:1:1 and 1:2:1 mixed-ligand complexes of rare-earth elements with acetylacetone and acrylic, methacrylic, maleic, and fumaric acids were analyzed. The complexes undergo inner-sphere structural transformations involving different modes of coordination of the unsaturated acid, which is capable of coordination to the central ion through both the carboxylic group and {pi} electrons of the double bond. The possibility of determining equilibrium constants and limiting chemical shifts of the isomeric forms of the complexes was demonstrated. 9 refs., 4 figs.

  15. Systematic Structural Elucidation for the Protonated Form of Rare Earth Bis(porphyrinato) Double-Decker Complexes: Direct Structural Evidence of the Location of the Attached Proton.

    PubMed

    Yamashita, Ken-Ichi; Sakata, Naoya; Ogawa, Takuji

    2016-09-01

    Direct structural evidence of the presence and location of the attached proton in the protonated form of rare earth bis(porphyrinato) double-decker complexes is obtained from an X-ray diffraction study of single crystals for a series of protonated forms of bis(tetraphenylporphyrinato) complexes [M(III)(tpp)(tppH)] (M = Tb, Y, Sm, Nd, and La). When CHCl3 is used as a solvent for crystallization of the complexes, their nondisordered molecular structures are obtained and the attached proton is identified on one of the eight nitrogen atoms. Use of other solvents affords another type of crystal, in which the position of the proton is disordered and thus the molecular structure is averaged. La complex also affords the disordered average structure even when CHCl3 is used for crystallization. A variable-temperature diffraction study for the Tb complex reveals that the dynamics of the proton in the nondisordered crystal is restricted. PMID:27541189

  16. Rare Variants in Transcript and Potential Regulatory Regions Explain a Small Percentage of the Missing Heritability of Complex Traits in Cattle

    PubMed Central

    Gonzalez-Recio, Oscar; Daetwyler, Hans D.; MacLeod, Iona M.; Pryce, Jennie E.; Bowman, Phil J.; Hayes, Ben J.; Goddard, Michael E.

    2015-01-01

    The proportion of genetic variation in complex traits explained by rare variants is a key question for genomic prediction, and for identifying the basis of “missing heritability”–the proportion of additive genetic variation not captured by common variants on SNP arrays. Sequence variants in transcript and regulatory regions from 429 sequenced animals were used to impute high density SNP genotypes of 3311 Holstein sires to sequence. There were 675,062 common variants (MAF>0.05), 102,549 uncommon variants (0.01rare variants (MAF<0.01). We describe a novel method for estimating the proportion of the rare variants that are sequencing errors using parent-progeny duos. We then used mixed model methodology to estimate the proportion of variance captured by these different classes of variants for fat, milk and protein yields, as well as for fertility. Common sequence variants captured 83%, 77%, 76% and 84% of the total genetic variance for fat, milk, and protein yields and fertility, respectively. This was between 2 and 5% more variance than that captured from 600k SNPs on a high density chip, although the difference was not significant. Rare variants captured 3%, 0%, 1% and 14% of the genetic variance for fat, milk and protein yields, and fertility respectively, whereas pedigree explained the remaining amount of genetic variance (none for fertility). The proportion of variation explained by rare variants is likely to be under-estimated due to reduced accuracies of imputation for this class of variants. Using common sequence variants slightly improved accuracy of genomic predictions for fat and milk yield, compared to high density SNP array genotypes. However, including rare variants from transcript regions did not increase the accuracy of genomic predictions. These results suggest that rare variants recover a small percentage of the missing heritability for complex traits, however very large reference sets will be required to exploit this to

  17. The Role of Defect Complexes in the Magneto-Optical Properties of Rare Earth Doped Gallium Nitride

    NASA Astrophysics Data System (ADS)

    Mitchell, Brandon

    Wide band gap semiconductors doped with rare earth ions (RE) have shown great potential for applications in optoelectronics, photonics, and spintronics. The 1.54mum Erbium (Er) emission has been extensively utilized in optical fiber communications, and Europium (Eu) is commonly used as a red color component for LEDs and fluorescence lamps. For the realization of spintronic-type devices, a dilutely doped semiconductor that exhibits room temperature ferromagnetic behavior would be desirable. Such behavior has been observed in GaN:Er. Furthermore, it was demonstrated that strain may play an important role in the control of this ferromagnetism; however, this requires further investigation. One motivation of this work is the realization of an all solid state white light source monolithically integrated into III/V nitride semiconductor materials, ideally GaN. For this, the current AlGaAs-based LEDs need to be replaced. One approach for achieving efficient red emission from GaN is dilute doping with fluorescent ions. In this regard, Eu has consistently been the most promising candidate as a dopant in the active layer for a red, GaN based, LED due to the sharp 5D0 to 7F2 transitions that result in red emission around 620nm. The success of GaN:Eu as the active layer for a red LED is based on the ability for the Eu ions to be efficiently excited by electron hole pairs. Thus, the processes by which energy is transferred from the host to the Eu ions has been studied. Complications arise, however, from the fact that Eu ions incorporate into multiple center environments, the structures of which are found to have a profound influence on the excitation pathways and efficiencies of the Eu ion. Therefore the nature of Eu incorporation and the resulting luminescence efficiency in GaN has been extensively investigated. By performing a comparative study on GaN:Eu samples grown under a variety of controlled conditions and using a variety of experimental techniques, the majority site has

  18. Extensive complex odontoma in the maxillary sinus pushing 3rd molar near the orbital floor causing transient diplopia and chronic sinusitis: a rare presentation and surgical management.

    PubMed

    Gupta, Monika; Das, Debdutta

    2015-03-01

    Odontoma is a mixed odontogenic hamartoma involving both epithelial and mesenchymal tissues. If left untreated, it can lead to complications in certain conditions. Here is a rare presentation of an extensive complex odontoma in maxillary sinus pushing third molar near the orbital floor causing transient diplopia in upward gaze occasionally and chronic sinusitis. Although odontomata are not uncommon and are familiar to practitioners, but some aggressive cases may cause problematic sequelae. Even postoperative complications may result if oral surgeons are not aware of the potential pitfalls associated with the surgical removal of large maxillary antrum odontomata. This article reports a rare presentation which can be considered unique because when obstruction of sinus drainage is evident, serious complications such as orbital infections, epidural and subdural empyema, meningitis, cerebritis, cavernous sinus thrombosis, brain abscess and death can occur. It also addresses points and pitfalls concerning surgery to remove odontoma. PMID:25848139

  19. Polygenic transmission and complex neuro developmental network for attention deficit hyperactivity disorder: genome-wide association study of both common and rare variants.

    PubMed

    Yang, Li; Neale, Benjamin M; Liu, Lu; Lee, S Hong; Wray, Naomi R; Ji, Ning; Li, Haimei; Qian, Qiujin; Wang, Dongliang; Li, Jun; Faraone, Stephen V; Wang, Yufeng; Doyle, Alysa E; Reif, Andreas; Rothenberger, Aribert; Franke, Barbara; Sonuga-Barke, Edmund J S; Steinhausen, Hans-Christoph; Buitelaar, Jan K; Kuntsi, Jonna; Biederman, Joseph; Lesch, Klaus-Peter; Kent, Lindsey; Asherson, Philip; Oades, Robert D; Loo, Sandra K; Nelson, Stan F; Faraone, Stephen V; Smalley, Susan L; Banaschewski, Tobias; Arias Vasquez, Alejandro; Todorov, Alexandre; Charach, Alice; Miranda, Ana; Warnke, Andreas; Thapar, Anita; Neale, Benjamin M; Cormand, Bru; Freitag, Christine; Mick, Eric; Mulas, Fernando; Middleton, Frank; HakonarsonHakonarson, Hakon; Palmason, Haukur; Schäfer, Helmut; Roeyers, Herbert; McGough, James J; Romanos, Jasmin; Crosbie, Jennifer; Meyer, Jobst; Ramos-Quiroga, Josep Antoni; Sergeant, Joseph; Elia, Josephine; Langely, Kate; Nisenbaum, Laura; Romanos, Marcel; Daly, Mark J; Ribasés, Marta; Gill, Michael; O'Donovan, Michael; Owen, Michael; Casas, Miguel; Bayés, Mònica; Lambregts-Rommelse, Nanda; Williams, Nigel; Holmans, Peter; Anney, Richard J L; Ebstein, Richard P; Schachar, Russell; Medland, Sarah E; Ripke, Stephan; Walitza, Susanne; Nguyen, Thuy Trang; Renner, Tobias J; Hu, Xiaolan

    2013-07-01

    Attention-deficit hyperactivity disorder (ADHD) is a complex polygenic disorder. This study aimed to discover common and rare DNA variants associated with ADHD in a large homogeneous Han Chinese ADHD case-control sample. The sample comprised 1,040 cases and 963 controls. All cases met DSM-IV ADHD diagnostic criteria. We used the Affymetrix6.0 array to assay both single nucleotide polymorphisms (SNPs) and copy number variants (CNVs). Genome-wide association analyses were performed using PLINK. SNP-heritability and SNP-genetic correlations with ADHD in Caucasians were estimated with genome-wide complex trait analysis (GCTA). Pathway analyses were performed using the Interval enRICHment Test (INRICH), the Disease Association Protein-Protein Link Evaluator (DAPPLE), and the Genomic Regions Enrichment of Annotations Tool (GREAT). We did not find genome-wide significance for single SNPs but did find an increased burden of large, rare CNVs in the ADHD sample (P = 0.038). SNP-heritability was estimated to be 0.42 (standard error, 0.13, P = 0.0017) and the SNP-genetic correlation with European Ancestry ADHD samples was 0.39 (SE 0.15, P = 0.0072). The INRICH, DAPPLE, and GREAT analyses implicated several gene ontology cellular components, including neuron projections and synaptic components, which are consistent with a neurodevelopmental pathophysiology for ADHD. This study suggested the genetic architecture of ADHD comprises both common and rare variants. Some common causal variants are likely to be shared between Han Chinese and Caucasians. Complex neurodevelopmental networks may underlie ADHD's etiology. PMID:23728934

  20. Rare 'head-to-tail' arrangement of guest molecules in the inclusion complexes of (+)- and (-)-menthol with β-cyclodextrin

    NASA Astrophysics Data System (ADS)

    Ceborska, Magdalena; Asztemborska, Monika; Lipkowski, Janusz

    2012-11-01

    The inclusion of (+)- and (-)-menthols in β-cyclodextrin has been studied by X-ray crystallography. The obtained [2:2] complexes show typical for β-cyclodextrin form of head-to-head dimer. In both (+)- and (-)-cases, the menthol molecule in one of cyclodextrins forming dimer exhibits disorder and occupies two major sites. Also both of the diastereoisomeric complexes show unusual 'head to tail' arrangement of guest molecules - two guest molecules are differently oriented inside β-cyclodextrin cavity. Stability constants for both complexes in solution were measured.

  1. Most of rare missense alleles in humans are deleterious:implications for evolution of complex disease and associationstudies

    SciTech Connect

    Kryukov, Gregory V.; Pennacchio, Len A.; Sunyaev, Shamil R.

    2006-10-24

    The accumulation of mildly deleterious missense mutations inindividual human genomes has been proposed to be a genetic basis forcomplex diseases. The plausibility of this hypothesis depends onquantitative estimates of the prevalence of mildly deleterious de novomutations and polymorphic variants in humans and on the intensity ofselective pressure against them. We combined analysis of mutationscausing human Mendelian diseases, human-chimpanzee divergence andsystematic data on human SNPs and found that about 20 percent of newmissense mutations in humans result in a loss of function, while about 27percent are effectively neutral. Thus, more than half of new missensemutations have mildly deleterious effects. These mutations give rise tomany low frequency deleterious allelic variants in the human populationas evident from a new dataset of 37 genes sequenced in over 1,500individual human chromosomes. Surprisingly, up to 70 percent of lowfrequency missense alleles are mildly deleterious and associated with aheterozygous fitness loss in the range 0.001-0.003. Thus, the low allelefrequency of an amino acid variant can by itself serve as a predictor ofits functional significance. Several recent studies have reported asignificant excess of rare missense variants in disease populationscompared to controls in candidate genes or pathways. These studies wouldbe unlikely to work if most rare variants were neutral or if rarevariants were not a significant contributor to the genetic component ofphenotypic inheritance. Our results provide a justification for thesetypes of candidate gene (pathway) association studies and imply thatmutation-selection balance may be a feasible mechanism for evolution ofsome common diseases.

  2. Mixed-ligand complex compounds of rare-earth elements (REE) with acetylacetone and fumaric or maleic acid

    SciTech Connect

    Panyushkin, V.T.; Akhrimenko, N.V.

    1994-10-01

    Previously the authors investigated the possibility of synthesis of the f-block element mixed complexes with {beta}-diketones and organic unsaturated acids. The mixed-ligand complexes of lanthanides [Ln = Nd(III), Sm(III), Eu(III), Tb(III), Dy(III), Ho(III), and Yb(III)] with acetylacetone (acac) and fumaric or maleic acid (AcidH{sub 2}) were synthesized. The mixed-ligand complexes were prepared by the interaction of REE tris(acetylacetonates) [Ln(acac){sub 3}{center_dot} 3H{sub 2}O] with half as much excess of the organic acid in a solution of diethyl ether. According to the data of elemental analysis and thermogravimetric and spectroscopic investigations, the mixed complexes studied are of composition Ln(acac){sub 2}(AcidH){center_dot}H{sub 2}O.

  3. Synthesis, structure, infrared and fluorescence spectra of new rare earth complexes with 6-hydroxy chromone-3-carbaldehyde benzoyl hydrazone

    NASA Astrophysics Data System (ADS)

    Wang, Bao-Dui; Yang, Zheng-Yin; Zhang, Ding-Wa; Wang, Yan

    2006-01-01

    A novel 6-hydroxy chromone-3-carbaldehyde benzoyl hydrazone ligand and its four complexes, [LnL2(NO3)2]NO3 [Ln = Eu(1), Sm(2), Tb(3), Dy(4)], were synthesized. The complexes were characterized by the elemental analyses, molar conductivity and IR spectra. The crystal and molecular structure of Sm(III) complex was determined by single-crystal X-ray diffraction: crystallized in the triclinic system, space group P-1, Z = 1, a = 11.037(4) Å, b = 14.770(5) Å, c = 15.032(7) Å, α = 60.583(4), β = 75.528(7), γ = 88.999(4), R1 = 0.0349. The fluorescence properties of complexes in the solid state and in the organic solvent were studied in detail, respectively. Under the excitation of ultraviolet light, strong red fluorescence of solid europium complex was observed. But the green fluorescence of solid terbium complex was not observed. These observations show that the ligand favor energy transfers to the emitting energy level of Eu3+. Some factors that influence the fluorescent intensity were also discussed.

  4. 1H-NMR studies on the ternary complexes of rare-earth ions with thenoyltrifluoroacetone and polyethers in dichloromethane.

    PubMed

    Gagabe, Gene Frederick; Satoh, Keiichi; Sawada, Kiyoshi

    2009-07-28

    The structures of the ternary complexes of lanthanoid and yttrium (Ln3+)-thenoyltrifluoroacetonates (tta-) with polyether (POE) in organic phase were investigated by 1H-NMR spectroscopy, where the POEs are crown ethers (18-crown-6 and benzo-18-crown-6) and monodispersed linear polyethers (DEOn: HO-(CH2CH2O-)nC12H25, where n=4, 6, 8). The changes in chemical shift of methylene protons of POE by addition of the adduct complex [Ln(tta)3(POE)] were measured at various Ln3+-to-POE concentration ratios. Chemical shift changes for each proton of POE by the formation of [Ln(tta)3(POE)] were determined. Results revealed that oxygen atoms at the hydroxyl terminal of linear POE have higher tendency to coordinate to the metal ion in [Ln(tta)3] complex. Three (for La3+) or two (for Lu3+ or Y3+) oxygen atoms of the POE coordinate to the metal ion without substitution of tta- ligands to satisfy the metal ion's coordination number of nine or eight, respectively. In the case of 18-membered crown ether complexes, La3+ is incorporated inside the cavity of the POE, displacing one of the three tta- from the inner coordination sphere while the other two remain coordinated to the metal ion. On the other hand, for the adduct of Y3+ complex with crown ether, all three tta- ligands are directly coordinating to the metal ion. PMID:19587993

  5. Antihuman Immunodeficiency Virus Type 1 (HIV-1) Activity of Rare Earth Metal Complexes of 4-Hydroxycoumarins in Cell Culture

    PubMed Central

    Manolov, Ilia; Raleva, Sevda; Genova, Petya; Savov, Alexey; Froloshka, Liliana; Dundarova, Daniela; Argirova, Radka

    2006-01-01

    The cerium Ce(III), lanthanum La(III), and neodymium Nd(III) complexes with 4-hydroxy-3-(3-oxo-1-phenylbutyl)-2H-1-benzopyran-2-one (warfarin) (W) and 3,3′-benzylidenebis[4-hydroxycoumarin] (1) were synthesized and studied for the first time for cytotoxicity (on MT-2 cells) and as anti-HIV agents under acute and chronic infection. The complexes were characterized by different physicochemical methods: mass spectrometry, 1H NMR, 13C NMR, and IR spectroscopy. The spectra of the complexes were interpreted on the basis of comparison with the spectrum of the free ligands. Anti-HIV effect of the complexes/ligands was measured in MT-2 cells by microtiter infection assay. Detection of endogenous reverse transcriptase (RT) activity and RT processivity by PCR indicative for proviral DNA synthesis demonstrated that anti-HIV activity has not been linked to early stages of viral replication. No effect on late steps of viral replication has been found using cells chronically producing HIV-1LAI virus. La(W) demonstrated anti-HIV activity (IC50=21.4 μM) close to maximal nontoxic concentration. Nd(W), Ce(1), and Nd(1) demonstrated limited anti-HIV potency, so none of the complexes seems appropriate to be used in clinic. Further targeting of HIV-1 inhibition by La(W) is under progress. PMID:17497016

  6. Syntheses, structures and properties of ruthenium complexes of tridentate ligands: isolation and characterization of a rare example of ruthenium nitrosyl complex containing {RuNO}5 moiety.

    PubMed

    Ghosh, Kaushik; Kumar, Rajan; Kumar, Sushil; Meena, Jay Singh

    2013-10-01

    Novel ruthenium complexes [Ru(L(1))(NO)Cl2] (1), [Ru(L(2))(PPh3)Cl2] (2), [Ru(L(2))(PPh3)(NO2)Cl] (3) and [Ru(L(2))(PPh3)(NO)Cl](ClO4)2 (4) (where L(1)H = N'-phenyl-N'-(pyridin-2-yl)picolinohydrazide and L(2) = (1-phenyl-1-(pyridin-2-yl)-2-(pyridin-2-ylmethylene)hydrazine) were synthesized. These complexes were characterized by using IR, UV-Vis, elemental analysis, electrochemical and NMR spectral studies. The molecular structures of nitrosyl complexes 1 and 4 were determined by X-ray crystallographic studies. Complexes 1 and 4 readily released NO under visible and ultraviolet light and free NO was transferred to reduced myoglobin. The amount of photoreleased NO was estimated using Griess reagent assay. During photolysis of NO, the generation of reactive nitrogen or/and reactive oxygen species was determined by DPPH (2,2-diphenyl-1-picrylhydrazine) radical quenching studies under aerobic conditions. A paramagnetic complex [Ru(L(2))(PPh3)(NO)Cl](NO3)3 (5) was synthesized via chemical oxidation of 4 with an excess of ceric ammonium nitrate (CAN) in acetonitrile. Complex 5 was characterized by UV-Vis, IR, elemental analysis and EPR spectral studies which authenticated the presence of the {RuNO}(5) moiety in 5. Theoretical investigation by DFT calculation supported the oxidation of complex 4 having {RuNO}(6) species and the formation of 5 containing {RuNO}(5). PMID:23893046

  7. Rare-earth metal methylidene complexes with Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3 core structure.

    PubMed

    Schädle, Dorothea; Meermann-Zimmermann, Melanie; Maichle-Mössmer, Cäcilia; Schädle, Christoph; Törnroos, Karl W; Anwander, Reiner

    2015-11-01

    Trinuclear rare-earth metal methylidene complexes with a Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3 structural motif were synthesized by applying three protocols. Polymeric [LuMe3]n (1-Lu) reacts with the sterically demanding amine H[NSiMe3(Ar)] (Ar = C6H3iPr2-2,6) in tetrahydrofuran via methane elimination to afford isolable monomeric [NSiMe3(Ar)]LuMe2(thf)2 (4-Lu). The formation of trinuclear rare-earth metal tetramethyl methylidene complexes [NSiMe3(Ar)]3Ln3(μ3-CH2)(μ3-Me)(μ2-Me)3(thf)3 (7-Ln; Ln = Y, Ho, Lu) via reaction of [LnMe3]n (1-Ln; Ln = Y, Ho, Lu) with H[NSiMe3(Ar)] is proposed to occur via an "intermediate" species of the type [NSiMe3(Ar)]LnMe2(thf)x and subsequent C-H bond activation. Applying Lappert's concept of Lewis base-induced methylaluminate cleavage, compounds [NSiMe3(Ar)]Ln(AlMe4)2 (5-Ln; Ln = Y, La, Nd, Ho) were converted into methylidene complexes 7-Ln (Ln = Y, Nd, Ho) in the presence of tetrahydrofuran. Similarly, tetramethylgallate complex [NSiMe3(Ar)]Y(GaMe4)2 (6-Y) could be employed as a synthesis precursor for 7-Y. The molecular composition of complexes 4-Ln, 5-Ln, 6-Y and 7-Ln was confirmed by elemental analyses, FTIR spectroscopy, (1)H and (13)C NMR spectroscopy (except for holmium derivatives) and single-crystal X-ray diffraction. The Tebbe-like reactivity of methylidene complex 7-Nd with 9-fluorenone was assessed affording oxo complex [NSiMe3(Ar)]3Nd3(μ3-O)(μ2-Me)4(thf)3 (8-Nd). The synthesis of 5-Ln yielded [NSiMe3(Ar)]2Ln(AlMe4) (9-Ln; Ln = La, Nd) as minor side-products, which could be obtained in moderate yields when homoleptic Ln(AlMe4)3 were treated with two equivalents of K[NSiMe3(Ar)]. PMID:26418665

  8. Spectroscopic identification of higher-order rare gas-dihalogen complexes with different geometries: He(2,3)...Br(2) and He(2,3)...ICl.

    PubMed

    Boucher, David S; Darr, Joshua P; Strasfeld, David B; Loomis, Richard A

    2008-12-25

    Rovibronic transitions of multiple conformers of the He(2)...(79)Br(2)(X, v'' = 0), He(3)...(79)Br(2)(X, v'' = 0), He(2)...I(35)Cl(X, v'' = 0), and He(3)...I(35)Cl(X, v'' = 0) complexes stabilized in a pulsed, supersonic expansion are observed in action spectra recorded in the B-X region of the dihalogens. In addition to features associated with He(2)...(79)Br(2) and He(2)...I(35)Cl complexes with the rare gas atoms localized in the toroidal potential well lying in a plane perpendicular to the dihalogen bond, those associated with a ground-state conformer that has one He atom localized in the toroidal potential and the other He atom localized in the linear well at the end of the dihalogen moiety are also identified. Transitions of at least three conformers of the He(3)...Br(2) complex and two conformers of the He(3)...ICl complex are also observed. The relative populations of the different conformers are found to depend on where along the supersonic expansion the spectra are recorded, and thus on the local temperature regime sampled. The He(2)...(79)Br(2) and He(2)...I(35)Cl conformers with one He atom in each well are found to be the more stable conformers. PMID:19053811

  9. Infection of African buffalo (Syncerus caffer) by oryx bacillus, a rare member of the antelope clade of the Mycobacterium tuberculosis complex.

    PubMed

    Gey van Pittius, Nicolaas C; Perrett, Keith D; Michel, Anita L; Keet, Dewald F; Hlokwe, Tiny; Streicher, Elizabeth M; Warren, Robin M; van Helden, Paul D

    2012-10-01

    Mycobacterium tuberculosis complex species cause tuberculosis disease in animals and humans. Although they share 99.9% similarity at the nucleotide level, several host-adapted ecotypes of the tubercule bacilli have been identified. In the wildlife setting, probably the most well-known member of this complex is Mycobacterium bovis, the causative agent of bovine tuberculosis. The recently described oryx bacillus is an extremely rare slow-growing member of the antelope clade of the M. tuberculosis complex and is closely related to the dassie bacillus, Mycobacterium africanum and Mycobacterium microti. The antelope clade is a group of strains apparently host adapted to antelopes, as most described infections were associated with deer and antelope, most specifically the Arabian oryx (Oryx leucoryx). In this study, oryx bacillus was isolated from a free-ranging adult female African buffalo (Syncerus caffer), in good physical condition, which tested strongly positive on three consecutive comparative intradermal tuberculin tests. Upon necropsy, a single pulmonary granuloma and an active retropharyngeal lymph node was found. Comprehensive molecular genetic assays were performed, which confirmed that the causative microorganism was not M. bovis but oryx bacillus. Oryx bacillus has never been reported in Southern Africa and has never been found to infect African buffalo. The identification of this microorganism in buffalo is an important observation in view of the large and ever-increasing epidemic of the closely related M. tuberculosis complex species M. bovis in some African buffalo populations in South Africa. PMID:23060486

  10. Extraction Separation of Rare-Earth Ions via Competitive Ligand Complexations between Aqueous and Ionic-Liquid Phases

    SciTech Connect

    Luo, Huimin; Sun, Xiaoqi; Bell, Jason R; Dai, Sheng

    2011-01-01

    The extraction separation of rare earth elements is the most challenging separation processes in hydrometallurgy and advanced nuclear fuel cycles. The TALSPEAK process (Trivalent Actinide Lanthanide Separations by Phosphorus-reagent Extraction from Aqueous Komplexes) is a prime example of these separation processes. The objective of this paper is to explore the use of ionic liquids (ILs) for the TALSPEAK-like process, to further enhance its extraction efficiencies for lanthanides, and to investigate the potential of using this modified TALSPEAK process for separation of lanthanides among themselves. Eight imidazolium ILs ([Cnmim][NTf2] and [Cnmim][BETI], n=4,6,8,10) and one pyrrolidinium IL ([C4mPy][NTf2]) were investigated as diluents using di(2-ethylhexyl)phosphoric acid (HDEHP) as an extractant for separation of lanthanide ions from aqueous solutions of 50 mM glycolic acid or citric acid and 5 mM diethylenetriamine pentaacetic acid (DTPA). The extraction efficiencies were studied in comparison with diisopropylbenzene (DIPB), an organic solvent used as diluent for the conventional TALSPEAK extraction system. Excellent extraction efficiencies and selectivities were found for a number of lanthanide ions using HDEHP as an extractant in these ILs. The effects of different alkyl chain lengths in the cations of ILs and anions on extraction efficiencies and selectivities of lanthanide ions are also presented in this paper.

  11. Expanding rare-earth oxidation state chemistry to molecular complexes of holmium(II) and erbium(II).

    PubMed

    MacDonald, Matthew R; Bates, Jefferson E; Fieser, Megan E; Ziller, Joseph W; Furche, Filipp; Evans, William J

    2012-05-23

    The first molecular complexes of holmium and erbium in the +2 oxidation state have been generated by reducing Cp'(3)Ln [Cp' = C(5)H(4)SiMe(3); Ln = Ho (1), Er (2)] with KC(8) in the presence of 18-crown-6 in Et(2)O at -35 °C under argon. Purification and crystallization below -35 °C gave isomorphous [(18-crown-6)K][Cp'(3)Ln] [Ln = Ho (3), Er (4)]. The three Cp' ring centroids define a trigonal-planar geometry around each metal ion that is not perturbed by the location of the potassium crown cation near one ring with K-C(Cp') distances of 3.053(8)-3.078(2) Å. The metrical parameters of the three rings are indistinguishable within the error limits. In contrast to Ln(2+) complexes of Eu, Yb, Sm, Tm, Dy, and Nd, 3 and 4 have average Ln-(Cp' ring centroid) distances only 0.029 and 0.021 Å longer than those of the Ln(3+) analogues 1 and 2, a result similar to that previously reported for the 4d(1) Y(2+) complex [(18-crown-6)K][Cp'(3)Y] (5) and the 5d(1) La(2+) complex [K(18-crown-6)(Et(2)O)][Cp″(3)La] [Cp″ = 1,3-(Me(3)Si)(2)C(5)H(3)]. Surprisingly, the UV-vis spectra of 3 and 4 are also very similar to that of 5 with two broad absorptions in the visible region, suggesting that 3-5 have similar electron configurations. Density functional theory calculations on the Ho(2+) and Er(2+) species yielded HOMOs that are largely 5d(z(2)) in character and supportive of 4f(10)5d(1) and 4f(11)5d(1) ground-state configurations, respectively. PMID:22583320

  12. On the formation and structure of rare-earth element complexes in aqueous solutions under hydrothermal conditions with new data on gadolinium aqua and chloro complexes

    USGS Publications Warehouse

    Mayanovic, Robert A.; Anderson, Alan J.; Bassett, William A.; Chou, I.-Ming

    2007-01-01

    Synchrotron X-ray spectroscopy experiments were made on the Gd(III) aqua and chloro complexes in low pH aqueous solutions at temperatures ranging from 25 to 500????C and at pressures up to 480??MPa using a hydrothermal diamond anvil cell. Analysis of fluorescence Gd L3-edge X-ray absorption fine structure (XAFS) spectra measured from a 0.006m Gd/0.16m HNO3 aqueous solution at temperatures up to 500????C and at pressures up to 260??MPa shows that the Gd-O distance of the Gd3+ aqua ion decreases steadily at a rate of ??? 0.007??A??/100????C whereas the number of coordinated H2O molecules decreases from 9.0 ?? 0.5 to 7.0 ?? 0.4. The loss of water molecules in the Gd3+ aqua ion inner hydration shell over this temperature range (a 22% reduction) is smaller than exhibited by the Yb3+ aqua ion (42% reduction) indicating that the former is significantly more stable than the later. We conjecture that the anomalous enrichment of Gd reported from measurement of REE concentrations in ocean waters may be attributed to the enhanced stability of the Gd3+ aqua ion relative to other REEs. Gd L3-edge XAFS measurements of 0.006m and 0.1m GdCl3 aqueous solutions at temperatures up to 500????C and pressures up to 480??MPa reveal that the onset of significant Gd3+-Cl- association occurs around 300????C. Partially-hydrated stepwise inner-sphere complexes most likely of the type Gd(H2O)??-nCln+3-n occur in the chloride solutions at higher temperatures, where ?? ??? 8 at 300????C decreasing slightly to an intermediate value between 7 and 8 upon approaching 500????C. This is the first direct evidence for the occurrence of partially-hydrated REE Gd (this study) and Yb [Mayanovic, R.A., Jayanetti, S., Anderson, A.J., Bassett, W.A., Chou, I-M., 2002a. The structure of Yb3+ aquo ion and chloro complexes in aqueous solutions at up to 500 ??C and 270 MPa. J. Phys. Chem. A 106, 6591-6599.] chloro complexes in hydrothermal solutions. The number of chlorides (n) of the partially-hydrated Gd

  13. Rare evidence for formation of garnet + corundum during isobaric cooling of ultrahigh temperature metapelites: New insights for retrograde P-T trajectory of the Highland Complex, Sri Lanka

    NASA Astrophysics Data System (ADS)

    Dharmapriya, P. L.; Malaviarachchi, Sanjeeva P. K.; Galli, Andrea; Su, Ben-Xun; Subasinghe, N. D.; Dissanayake, C. B.

    2015-04-01

    We report the occurrence of coexisting garnet + corundum in spinel- and corundum-bearing, garnet-sillimanite-biotite-graphite gneiss (pelitic granulites) from the Highland Complex (HC), Sri Lanka. In the investigated pelitic granulites, two domains such as quartz-saturated and quartz-undersaturated are distinguishable. The quartz-saturated domains consist of porphyroblastic garnet, quartz, plagioclase, alkali-feldspar and biotite flakes rimming garnet. The quartz-undersaturated domains are constituted of two generations of garnet (Grt1 and Grt2), sillimanite, plagioclase, alkali-feldspar, corundum, spinel and biotite. Grt1 encloses rare Ti-rich biotite and numerous rutile needles and apatite rods. Grt2 contains rare sillimanite and/or spinel inclusions. Corundum occurs in mutual contact with Grt2, partially embedded at the rim or as an inclusions in Grt2. Thermobarometry on inclusion phases in Grt1 indicates that during the prograde history pelitic granulites attained a P of 10.5-11 kbar at T of ~ 850 °C. Textural observations coupled with both pseudosections calculated in the NCKFMASHTMnO system and Ti-in-Garnet geothermobarometry suggest that peak metamorphism occurred at ultrahigh temperature (UHT) conditions of 950-975 °C and pressures of 9-9.5 kbar. Peak T was followed by a period of isobaric cooling that formed corundum and Grt2 at approx. 930 °C along with exsolution of rutile needles and apatite rods in Grt1. Thermodynamic modelling confirms that corundum appears along an isobaric cooling path at about 920-930 °C and 9-9.5 kbar. Therefore, the investigated granulites provide a rare example of post-peak crystallization of garnet + corundum along a retrograde metamorphic trajectory under UHT conditions. Thus, isobaric cooling at the base of the crust could be regarded as an alternative process to form coexisting garnet + corundum.

  14. Compound inheritance of a low-frequency regulatory SNP and a rare null mutation in exon-junction complex subunit RBM8A causes TAR syndrome.

    PubMed

    Albers, Cornelis A; Paul, Dirk S; Schulze, Harald; Freson, Kathleen; Stephens, Jonathan C; Smethurst, Peter A; Jolley, Jennifer D; Cvejic, Ana; Kostadima, Myrto; Bertone, Paul; Breuning, Martijn H; Debili, Najet; Deloukas, Panos; Favier, Rémi; Fiedler, Janine; Hobbs, Catherine M; Huang, Ni; Hurles, Matthew E; Kiddle, Graham; Krapels, Ingrid; Nurden, Paquita; Ruivenkamp, Claudia A L; Sambrook, Jennifer G; Smith, Kenneth; Stemple, Derek L; Strauss, Gabriele; Thys, Chantal; van Geet, Chris; Newbury-Ecob, Ruth; Ouwehand, Willem H; Ghevaert, Cedric

    2012-04-01

    The exon-junction complex (EJC) performs essential RNA processing tasks. Here, we describe the first human disorder, thrombocytopenia with absent radii (TAR), caused by deficiency in one of the four EJC subunits. Compound inheritance of a rare null allele and one of two low-frequency SNPs in the regulatory regions of RBM8A, encoding the Y14 subunit of EJC, causes TAR. We found that this inheritance mechanism explained 53 of 55 cases (P < 5 × 10(-228)) of the rare congenital malformation syndrome. Of the 53 cases with this inheritance pattern, 51 carried a submicroscopic deletion of 1q21.1 that has previously been associated with TAR, and two carried a truncation or frameshift null mutation in RBM8A. We show that the two regulatory SNPs result in diminished RBM8A transcription in vitro and that Y14 expression is reduced in platelets from individuals with TAR. Our data implicate Y14 insufficiency and, presumably, an EJC defect as the cause of TAR syndrome. PMID:22366785

  15. Inheritance of low-frequency regulatory SNPs and a rare null mutation in exon-junction complex subunit RBM8A causes TAR

    PubMed Central

    Albers, Cornelis A; Paul, Dirk S; Schulze, Harald; Freson, Kathleen; Stephens, Jonathan C; Smethurst, Peter A; Jolley, Jennifer D; Cvejic, Ana; Kostadima, Myrto; Bertone, Paul; Breuning, Martijn H; Debili, Najet; Deloukas, Panos; Favier, Rémi; Fiedler, Janine; Hobbs, Catherine M; Huang, Ni; Hurles, Matthew E; Kiddle, Graham; Krapels, Ingrid; Nurden, Paquita; Ruivenkamp, Claudia A L; Sambrook, Jennifer G; Smith, Kenneth; Stemple, Derek L; Strauss, Gabriele; Thys, Chantal; van Geet, Christel; Newbury-Ecob, Ruth; Ouwehand, Willem H; Ghevaert, Cedric

    2012-01-01

    The exon-junction complex (EJC) performs essential RNA processing tasks1-5. Here, we describe the first human disorder, Thrombocytopenia with Absent Radii6 (TAR), caused by deficiency in one of the four EJC subunits. A compound inheritance mechanism of a rare null allele and one of two low-frequency SNPs in the regulatory regions of RBM8A, encoding the Y14 subunit of EJC, causes TAR. We found that this mechanism explained 53 of 55 cases (P<5×10−228) with the rare congenital malformation syndrome. Fifty-one of those 53 carried a previously associated7 submicroscopic deletion of 1q21.1; two carried a truncation or frameshift null mutation in RBM8A. We show that the two regulatory SNPs result in reduction of RBM8A transcription in vitro and that Y14 expression is reduced in platelets from TAR cases. Our data implicate Y14 insufficiency, and presumably EJC defect, as the cause of TAR syndrome. PMID:22366785

  16. NADPH oxidase complex and IBD candidate gene studies: identification of a rare variant in NCF2 that results in reduced binding to RAC2

    PubMed Central

    Muise, Aleixo M; Xu, Wei; Guo, Cong-Hui; Walters, Thomas D; Wolters, Victorien M; Fattouh, Ramzi; Lam, Grace Y; Hu, Pingzhao; Murchie, Ryan; Sherlock, Mary; Gana, Juan Cristóbal; Russell, Richard K; Glogauer, Michael; Duerr, Richard H; Cho, Judy H; Lees, Charlie W; Satsangi, Jack; Wilson, David C; Paterson, Andrew D; Griffiths, Anne M; Silverberg, Mark S; Brumell, John H

    2013-01-01

    Objective The NOX2 NADPH oxidase complex produces reactive oxygen species and plays a critical role in the killing of microbes by phagocytes. Genetic mutations in genes encoding components of the complex result in both X-linked and autosomal recessive forms of chronic granulomatous disease (CGD). Patients with CGD often develop intestinal inflammation that is histologically similar to Crohn's colitis, suggesting a common aetiology for both diseases. The aim of this study is to determine if polymorphisms in NOX2 NADPH oxidase complex genes that do not cause CGD are associated with the development of inflammatory bowel disease (IBD). Methods Direct sequencing and candidate gene approaches were used to identify susceptibility loci in NADPH oxidase complex genes. Functional studies were carried out on identified variants. Novel findings were replicated in independent cohorts. Results Sequence analysis identified a novel missense variant in the neutrophil cytosolic factor 2 (NCF2) gene that is associated with very early onset IBD (VEO-IBD) and subsequently found in 4% of patients with VEO-IBD compared with 0.2% of controls (p=1.3×10−5, OR 23.8 (95% CI 3.9 to 142.5); Fisher exact test). This variant reduced binding of the NCF2 gene product p67phox to RAC2. This study found a novel genetic association of RAC2 with Crohn's disease (CD) and replicated the previously reported association of NCF4 with ileal CD. Conclusion These studies suggest that the rare novel p67phox variant results in partial inhibition of oxidase function and are associated with CD in a subgroup of patients with VEO-IBD; and suggest that components of the NADPH oxidase complex are associated with CD. PMID:21900546

  17. Synthesis of main group, rare-earth, and d{sup 0} metal complexes containing beta-hydrogen

    SciTech Connect

    Yan, Ka King

    2013-01-01

    A series of organometallic compounds containing the tris(dimethylsilyl)methyl ligand are described. The potassium carbanions KC(SiHMe2)3 and KC(SiHMe2})3TMEDA are synthesized by deprotonation of the hydrocarbon HC(SiHMe2)3 with potassium benzyl. KC(SiHMe2)3TMEDA crystallizes as a dimer with two types of three-center-two-electron KH- Si interactions. Homoleptic Ln(III) tris(silylalkyl) complexes containing β-SiH groups M{C(SiHMe2)3}3 (Ln = Y, Lu, La) are synthesized from salt elimination of the corresponding lanthanide halide and 3 equiv. of KC(SiHMe2)3. The related reactions with Sc yield bis(silylalkyl) ate-complexes containing either LiCl or KCl. The divalent calcium and ytterbium compounds M{C(SiHMe2)3}2L (M = Ca, Yb; L = THF2 or TMEDA) are prepared from MI2 and 2 equiv of KC(SiHMe2)3. The compounds M{C(SiHMe2)3}2L (M = Ca, Yb; L = THF2 or TMEDA) and La{C(SiHMe2)3}3 react with 1 equiv of B(C6F5)3 to give 1,3- disilacyclobutane {Me2Si-C(SiHMe2)2}2 and MC(SiHMe2)3HB(C6F5)3L, and La{C(SiHMe2)3}2HB(C6F5)3, respectively. The corresponding reactions of Ln{C(SiHMe2)3}3 (Ln = Y, Lu) give the β-SiH abstraction product [{(Me2HSi)3C}2LnC(SiHMe2)2SiMe2][HB(C6F5)3] (Ln = Y, Lu), but the silene remains associated with the Y or Lu center. The abstraction reactions of M{C(SiHMe2)3}2L (M = Ca, Yb; L = THF2or TMEDA) and Ln{C(SiHMe2)3}3 (Ln = Y, Lu, La) and 2 equiv of B(C6

  18. Synthesis, structure and reactivity of dinuclear rare earth metal bis(o-aminobenzyl) complexes bearing a 1,4-phenylenediamidinate co-ligand.

    PubMed

    Li, Meng; Hong, Jianquan; Chen, Zhenxia; Zhou, Xigeng; Zhang, Lixin

    2013-06-21

    A series of phenylenediamidinate rare earth metal complexes 1,4-C6H4[C(NR)2Ln(o-CH2C6H4NMe2)2]2 (R = 2,6-(i)Pr2-C6H3, Ln = Y (2a), Lu (2b), Sc (2c)) were synthesized by deprotonation of 1,4-C6H4[C(NR)(NHR)]2 (1) with two equivalents of n-BuLi followed by reacting with two equivalents of anhydrous LnCl3 and subsequently four equivalents of Li(o-CH2C6H4NMe2), or by protolysis of [Ln(o-CH2C6H4NMe2)3] with 0.5 equivalent of 1 in THF or toluene. Treatment of complexes 2a and 2b with four equivalents of phenyl isocyanate and phenyl isothiocyanate gave the corresponding insertion products 1,4-C6H4[C(NR)2Ln{OC(CH2C6H4NMe2-o)NPh}2(THF)]2 (Ln = Y (3a), Lu (3b)) and 1,4-C6H4[C(NR)2Ln{SC(CH2C6H4NMe2-o)NPh}2]2 (Ln = Y (4a), Lu (4b)), respectively. The structures of 1, 3b, and 4a were established by X-ray diffraction studies. Complexes 2 show high activity for rac-lactide and ε-caprolactone polymerization; for the former a synergistic effect between two metal centers is observed. PMID:23598898

  19. Theoretical study of mixed LiLnX4 (Ln = La, Dy; X = F, Cl, Br, I) rare earth/alkali halide complexes.

    PubMed

    Groen, C P; Oskam, A; Kovács, A

    2000-12-25

    The structure, bonding and vibrational properties of the mixed LiLnX4 (Ln = La, Dy; X = F, Cl, Br, I) rare earth/alkali halide complexes were studied using various quantum chemical methods (HF, MP2 and the Becke3-Lee-Yang-Parr exchange-correlation density functional) in conjunction with polarized triple-zeta valence basis sets and quasi-relativistic effective core potentials for the heavy atoms. Our comparative study indicated the superiority of MP2 theory while the HF and B3-LYP methods as well as less sophisticated basis sets failed for the correct energetic relations. In particular, f polarization functions on Li and X proved to be important for the Li...X interaction in the complexes. From the three characteristic structures of such complexes, possessing 1-(C3v), 2-(C2v), or 3-fold coordination (C3v) between the alkali metal and the bridging halide atoms, the bi- and tridentate forms are located considerably lower on the potential energy surface then the monodentate isomer. Therefore only the bi- and tridentate isomers have chemical relevance. The monodentate isomer is only a high-lying local minimum in the case of X = F. For X = Cl, Br, and I this structure is found to be a second-order saddle point. The bidentate structure was found to be the global minimum for the systems with X = F, Cl, and Br. However, the relative stability with respect to the tridentate structure is very small (1-5 kJ/mol) for the heavier halide derivatives and the relative order is reversed in the case of the iodides. The energy difference between the three structures and the dissociation energy decrease in the row F to I. The ionic bonding in the complexes was characterized by natural charges and a topological analysis of the electron density distribution according to Bader's theorem. Variation of the geometrical and bonding characteristics between the lanthanum and dysprosium complexes reflects the effect of "lanthanide contraction". The calculated vibrational data indicate that

  20. Rare earth gas laser

    DOEpatents

    Krupke, W.F.

    1975-10-31

    A high energy gas laser with light output in the infrared or visible region of the spectrum is described. Laser action is obtained by generating vapors of rare earth halides, particularly neodymium iodide or, to a lesser extent, neodymium bromide, and disposing the rare earth vapor medium in a resonant cavity at elevated temperatures; e.g., approximately 1200/sup 0/ to 1400/sup 0/K. A particularly preferred gaseous medium is one involving a complex of aluminum chloride and neodymium chloride, which exhibits tremendously enhanced vapor pressure compared to the rare earth halides per se, and provides comparable increases in stored energy densities.

  1. Synthesis, structure and spectroscopic properties of complexes of rare earth dithiocarbamates with 2,2{prime}-bipyridyl or 1, 10-phenanthroline

    SciTech Connect

    Chengyong Su; Minyu Tan; Ning Tang; Xinmin Gan; Weisheng Liu

    1996-05-01

    Two series of rare earth complexes with the general formula [RE(Me{sub 2}Dtc){sub 3}](RE = La,Pr,Nd,Sm-Yb, Y;Me{sub 2}Dtc = N,N-dimethyldithiocarbamate; bipy = 2,2{prime}-bipyridyl) and [RE(Et{sub 2-}Dtc){sub 3}(phen)](RE = La,Pr,Nd,Sm-Lu, Y;Et{sub 2}Dtc = N,N-diethyldithiocarbamate; phen = 1, 10-phenanthroline) have been prepared and some of their chemical properties, IR spectra, electronic spectra and conductivity properties are reported. The structures of [Eu(Me{sub 2}Dtc){sub 3}(bipy)] and [Eu(Et{sub 2}Dtc){sub 3}(phen)] have been determined by single-crystal X-ray diffraction methods. [Eu(Et{sub 2}Dtc){sub 3}(phen)] crystallizes in the tetragonal system, space group I4{sub 1}/a with a = 16.753(1), c = 39.523 (3) {angstrom} and Z = 16, while [Eu(Et{sub 2}Dtc){sub 3}(phen)]crystallizes in the monoclinic system, space group P2{sub 1}/c with a = 17.029(3), b = 10.652(3), c = 18.726(3) {angstrom}, {beta} = 96.41(4){degrees} and Z = 4. The central Eu(III) atoms are both octa-coordinated and in a distorted square antiprismatic geometry, each being coordinated to six sulphur atoms of three bidentate dithiocarbamates and to two nitrogen atoms of bipy or phen ligands. Spectrum analyses indicate that both Me{sub 2}Dtc and Et{sub 2}Dtc show similar coordination structures in all complexes.

  2. Application of liver three-dimensional printing in hepatectomy for complex massive hepatocarcinoma with rare variations of portal vein: preliminary experience

    PubMed Central

    Xiang, Nan; Fang, Chihua; Fan, Yingfang; Yang, Jian; Zeng, Ning; Liu, Jun; Zhu, Wen

    2015-01-01

    Background: To discuss the role of Liver 3D printing in the treatment of complex massive hepatocarcinoma with rare variations of portal vein. Methods: Data of enhanced computed tomography (CT) were imported into the medical image three-dimensional visualization system (MI-3DVS) to create Standard Template Library (STL) files, which were read by 3D printer to construct life-size 3D physical liver model. The preoperative surgical planning was performed on the 3D model according to individualized segmentation, volume calculation, and virtual operation. Results: The 3D printing liver model was consistent with the model in MI-3DVS. The segment 4 portal vein (S4PV) was absent and variant S4PV originated from right anterior portal vein (RAPV). The preoperative surgical planning was designed according to the relationship between tumor and portal vein variation. Theoretically, the residual liver volume was 40.76%, if the right hemihepatctomy was carried out after the trunk of right portal vein (RPV) ligated. However, the actual residual volume was only 21.37% due to the variant S4PV originates from RAPV, thus, right trisegmentectomy would have to be performed. Interestingly, after optimization, the residual liver volume increased to 57.25% as narrow-margin right hemihepatectomy with the variant S4PV reserved were performed. The final resection was determined to be narrow-margin right hemihepatectomy. The actual surgical procedure was consistent with the preoperative surgical planning. Conclusion: Liver 3D printing may be a safe and effective technique to improve the success rate of surgery and reduce the operation risk for patients with complex massive hepatocarcinoma with variations of portal vein. PMID:26770510

  3. New reversed phase-high performance liquid chromatographic method for selective separation of yttrium from all rare earth elements employing nitrilotriacetate complexes in anion exchange mode.

    PubMed

    Dybczyński, Rajmund S; Kulisa, Krzysztof; Pyszynska, Marta; Bojanowska-Czajka, Anna

    2015-03-20

    Separation of Y from other rare earth elements (REE) is difficult because of similarity of its ionic radius to ionic radii of Tb, Dy and Ho. In the new RP-HPLC system with C18 column, tetra-n-butyl ammonium hydroxide (TBAOH) as an ion interaction reagent (IIR), nitrilotriacetic acid (NTA) as a complexing agent at pH=2.8-3.5, and post column derivatization with Arsenazo III, yttrium is eluted in the region of light REE, between Nd and Sm and is base line separated from Nd and Sm and even from promethium. Simple model employing literature data on complex formation of REE with NTA and based on anion exchange mechanism was developed to foresee the order of elution of individual REE. The model correctly predicted that lanthanides up to Tb will be eluted in the order of increasing Atomic Number (At.No.) but all heavier REE will show smaller retention factors than Tb. Concurrent UV/VIS detection at 658nm and the use of radioactive tracers together with γ-ray spectrometric measurements made possible to establish an unique elution order of elution of REE: La, Ce, Pr, Nd, Pm, Y, Sm, Er, Ho, Tm, Yb, Eu, Lu, Dy+Gd, Tb, Sc. The real place of Y however, in this elution series differs from that predicted by the model (Y between Sm and Eu). The method described in this work enables selective separation of Y from La, Ce, Pr, Nd, Pm, Sm and all heavier REE treated as a group. PMID:25700726

  4. Heterometallic Cu/Co and Cu/Co/Zn complexes bearing rare asymmetric tetranuclear cores: synthesis, structures, and magnetic and catalytic properties toward the peroxidative oxidation of cycloalkanes.

    PubMed

    Nesterov, Dmytro S; Kokozay, Volodymyr N; Jezierska, Julia; Pavlyuk, Oleksiy V; Boča, Roman; Pombeiro, Armando J L

    2011-05-16

    The three novel heterometallic complexes [CuCo(III)Co(II)(2)(MeDea)(3)Cl(3)(CH(3)OH)(0.55)(H(2)O)(0.45)](H(2)O)(0.45) (1), [CuCo(III)Zn(2)(MeDea)(3)Cl(3)(CH(3)OH)(0.74)(H(2)O)(0.26)](H(2)O)(0.26) (2), and [CuCo(III)Zn(2)(MeDea)(3)Cl(3)(DMF)] (3) have been prepared using a one-pot reaction of copper powder with cobalt chloride (1) and zinc nitrate (2, 3) in a methanol (1, 2) or dimethylformamide (3) solution of N-methyldiethanolamine. A search of the Cambridge Structural Database shows that the tetranuclear asymmetric cores M(4)(μ(3)-X)(μ-X)(5) of 1-3 represent an extremely rare case of M(4)X(6) arrays. The magnetic investigations of 1 disclose antiferromagnetic coupling in a Co(II)-Cu(II)-Co(II) exchange fragment with J(Co-Cu)/hc = -4.76 cm(-1), J(Co-Co)/hc = -2.76 cm(-1), and D(Co)/hc = +34.3 cm(-1). Compounds 1-3 act as precursors for the mild peroxidative oxidation of cyclohexane to cyclohexanol and cyclohexanone with overall yields up to 23%. The synthetic and structural features as well as the thermogravimetric behavior and electrospray ionization mass spectrometry data are discussed. PMID:21506552

  5. Spatial Dynamics of the Communities and the Role of Major Countries in the International Rare Earths Trade: A Complex Network Analysis

    PubMed Central

    Wang, Xibo; Ge, Jianping; Wei, Wendong; Li, Hanshi; Wu, Chen; Zhu, Ge

    2016-01-01

    Rare earths (RE) are critical materials in many high-technology products. Due to the uneven distribution and important functions for industrial development, most countries import RE from a handful of suppliers that are rich in RE, such as China. However, because of the rapid growth of RE exploitation and pollution of the mining and production process, some of the main suppliers have gradually tended to reduce the RE production and exports. Especially in the last decade, international RE trade has been changing in the trade community and trade volume. Based on complex network theory, we built an unweighted and weighted network to explore the evolution of the communities and identify the role of the major countries in the RE trade. The results show that an international RE trade network was dispersed and unstable because of the existence of five to nine trade communities in the unweighted network and four to eight trade communities in the weighted network in the past 13 years. Moreover, trade groups formed due to the great influence of geopolitical relations. China was often associated with the South America and African countries in the same trade group. In addition, Japan, China, the United States, and Germany had the largest impacts on international RE trade from 2002 to 2014. Last, some policy suggestions were highlighted according to the results. PMID:27137779

  6. Complex rare-earth tetrelides, RE5(SixGe(1-x))4: new materials for magnetic refrigeration and a superb playground for solid state chemistry.

    PubMed

    Miller, Gordon J

    2006-09-01

    A "giant magnetocaloric effect" discovered in 1997 for Gd5Si2Ge2 near room temperature has triggered optimism that environmentally-friendly, solid-state magnetic refrigeration may be viable to replace gas-compression technology in the near future. Gd5Si2Ge2 is one member of an extensive series of rare-earth compounds, RE5(SixGe(1-x))4. Due to the complexity of their structures and flexibility associated with chemical compositions, this series is an attractive "playground" to study the interrelationships among composition, structure, physical properties and chemical bonding. This tutorial review, which is directed toward students and researchers interested in structure-property relationships in solids, summarizes recent efforts concerning the synthesis, structure, physical properties, chemical bonding and chemical modifications of RE5(SixGe(1-x))4. A brief history of refrigerants, to present certain motivating factors for this research effort, as well as a brief overview of the magnetocaloric effect serves to introduce this review. PMID:16936928

  7. Upconverting rare-earth nanoparticles with a paramagnetic lanthanide complex shell for upconversion fluorescent and magnetic resonance dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Ji, Lei; Zhang, Bingbo; Yin, Peihao; Qiu, Yanyan; Song, Daqian; Zhou, Juying; Li, Qi

    2013-05-01

    Multi-modal imaging based on multifunctional nanoparticles is a promising alternative approach to improve the sensitivity of early cancer diagnosis. In this study, highly upconverting fluorescence and strong relaxivity rare-earth nanoparticles coated with paramagnetic lanthanide complex shells and polyethylene glycol (PEGylated UCNPs@DTPA-Gd3+) are synthesized as dual-modality imaging contrast agents (CAs) for upconverting fluorescent and magnetic resonance dual-modality imaging. PEGylated UCNPs@DTPA-Gd3+ with sizes in the range of 32-86 nm are colloidally stable. They exhibit higher longitudinal relaxivity and transverse relaxivity in water (r1 and r2 values are 7.4 and 27.8 s-1 per mM Gd3+, respectively) than does commercial Gd-DTPA (r1 and r2 values of 3.7 and 4.6 s-1 per mM Gd3+, respectively). They are found to be biocompatible. In vitro cancer cell imaging shows good imaging contrast of PEGylated UCNPs@DTPA-Gd3+. In vivo upconversion fluorescent imaging and T1-weighted MRI show excellent enhancement of both fluorescent and MR signals in the livers of mice administered PEGylated UCNPs@DTPA-Gd3+. All the experimental results indicate that the synthesized PEGylated UCNPs@DTPA-Gd3+ present great potential for biomedical upconversion of fluorescent and magnetic resonance dual-modality imaging applications.

  8. Spatial Dynamics of the Communities and the Role of Major Countries in the International Rare Earths Trade: A Complex Network Analysis.

    PubMed

    Wang, Xibo; Ge, Jianping; Wei, Wendong; Li, Hanshi; Wu, Chen; Zhu, Ge

    2016-01-01

    Rare earths (RE) are critical materials in many high-technology products. Due to the uneven distribution and important functions for industrial development, most countries import RE from a handful of suppliers that are rich in RE, such as China. However, because of the rapid growth of RE exploitation and pollution of the mining and production process, some of the main suppliers have gradually tended to reduce the RE production and exports. Especially in the last decade, international RE trade has been changing in the trade community and trade volume. Based on complex network theory, we built an unweighted and weighted network to explore the evolution of the communities and identify the role of the major countries in the RE trade. The results show that an international RE trade network was dispersed and unstable because of the existence of five to nine trade communities in the unweighted network and four to eight trade communities in the weighted network in the past 13 years. Moreover, trade groups formed due to the great influence of geopolitical relations. China was often associated with the South America and African countries in the same trade group. In addition, Japan, China, the United States, and Germany had the largest impacts on international RE trade from 2002 to 2014. Last, some policy suggestions were highlighted according to the results. PMID:27137779

  9. A New Series of Complexes Possessing Rare “Tertiary” Sulfonamide Nitrogen-to-Metal Bonds of Normal Length: fac-[Re(CO)3(N(SO2R)dien)]PF6 Complexes with Hydrophilic Sulfonamide Ligands

    PubMed Central

    Abhayawardhana, Pramuditha L.; Marzilli, Patricia A.; Fronczek, Frank R.

    2014-01-01

    Tertiary sulfonamide nitrogen-to-metal bonds of normal length are very rare. We recently discovered such a bond in one class of fac-[Re(CO)3(N(SO2R)(CH2Z)2)]n complexes (Z = 2-pyridyl) with N(SO2R)dpa ligands derived from di-(2-picolyl)amine (N(H)dpa). fac-[M(CO)3(N(SO2R)(CH2Z)2)]n agents (M = 186/188Re, 99mTc) could find use as radiopharmaceutical bioconjugates when R is a targeting moiety. However, the planar, electron-withdrawing 2-pyridyl groups of N(SO2R)dpa destabilize the ligand to base and create relatively rigid chelate rings, raising the possibility that the rare M– N(sulfonamide) bond is an artifact of a restricted geometry. Also, the hydrophobic 2-pyridyl groups could cause undesirable accumulation in the liver, limiting future use in radiopharmaceuticals. Our goal is to identify a robust, hydrophilic, and flexible N(CH2Z)2 chelate framework. New C2-symmetric ligands, N(SO2R)(CH2Z)2 with (Z = CH2NH2; R = Me, dmb, or tol), were prepared by treating N(H)dien(Boc)2, a protected diethylenetriamine (N(H)dien) derivative, with methanesulfonyl chloride (MeSO2Cl), 3,5-dimethylbenzenesulfonyl chloride (dmbSO2Cl), and 4-methylbenzenesulfonyl chloride (tolSO2Cl). Treatment of fac-[Re(CO)3(H2O)3]+ with these ligands, designated as N(SO2R)dien, afforded new fac-[Re(CO)3(N(SO2R)dien)]PF6 complexes. Comparing the fac-[Re(CO)3(N(SO2Me)dien)]PF6 and fac-[Re(CO)3(N(SO2Me)dpa)]PF6 complexes, we find that the ReI–N(sulfonamide) bonds are normal in length and statistically identical and that the methyl 13C NMR signal has an unusually upfield shift compared to that in the free ligand. We attribute this unusual upfield shift to the fact that the sulfonamide N undergoes an sp2-to-sp3 rehybridization upon coordination to ReI in both complexes. Thus, the sulfonamide N of N(SO2R)dien ligands is a good donor, even though the chelate rings are conformationally flexible. Addition of the strongly basic and potentially monodentate ligand, 4-dimethylaminopyridine, did not affect

  10. PS1-23: Capitalizing on the HMO Cancer Research Network (CRN): The Optimal Setting to Conduct Studies of Rare Complex Diseases

    PubMed Central

    Johnson, Christine Cole; Chao, Chun; Engel, Larry; Feigelson, Heather; Fortuny, Joan; Habel, Laurel; Koshiol, Jill; Roblin, Douglas; Spangler, Leslie; Wells, Karen; Yood, Marianne Ulcickas

    2013-01-01

    Background/Aims Rare cancers are challenging to study, both epidemiologically and clinically, as it is difficult to ascertain enough cases to achieve adequate statistical power or to be representative of a vast range of exposures. Further, as the complexity of unraveling the natural history of disease has increased, a large investigator team with diverse expertise is required to optimize the scientific contributions that can be mined from research projects. The HMOCRN provides a setting that can overcome these barriers. Although many studies evaluate all lymphomas combined, lymphoma consists of over 50 rare histological subtypes with varying incidence and survival rates and epidemiological features. Ideally, each histological subtype should be considered separately in etiological studies, but even the most common, diffuse large B cell lymphoma, has a SEER incidence of only 7.5 per 100,000 in men and 5.0 per 100,000 in women. Other lymphoma types range in incidence from <0.1 cases per 100,000 for NKT cell lymphoma to 2.8 per 100,000 for Hodgkin’s Disease in all race-sex groups combined, to the highest rate found for a population subgroup, only 8.8 per 100,000 for multiple myeloma in African American men. Methods We have assembled a multi-disciplinary team interested in lymphoma and pharmacoepidemiology that includes investigators with clinical, epidemiological and biostatistical expertise from six HMORN sites, two US universities, the NCI, and an international investigator who first initiated the project. Results Combining data from these HMOCRN sites from 1998–2008, we ascertained 1479 Hodgkin’s Disease cases, 3385 multiple myelomas, 771 T-cell lymphomas, (including 390 mycosis fungoides cases and 158 mature T-cell lymphomas), 3000 chronic lymphocytic leukemias, 1357 mature B cell lymphomas, 3883 diffuse large B cell lymphomas, 2188 follicular lymphomas, and 992 marginal zone B cell lymphomas. Conclusions These numbers provide a unique opportunity to analyze

  11. Bis(alkyl) rare-earth complexes supported by a new tridentate amidinate ligand with a pendant diphenylphosphine oxide group. Synthesis, structures and catalytic activity in isoprene polymerization.

    PubMed

    Tolpygin, Aleksei O; Glukhova, Tatyana A; Cherkasov, Anton V; Fukin, Georgy K; Aleksanyan, Diana V; Cui, Dongmei; Trifonov, Alexander A

    2015-10-01

    A new tridentate amidine 2-[Ph2P(O)]C6H4NHC(tBu)[double bond, length as m-dash]N(2,6-Me2C6H3) (1) bearing a side chain pendant Ph2P[double bond, length as m-dash]O group was synthesized and proved to be a suitable ligand for coordination to rare-earths ions. Bis(alkyl) complexes {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}Ln(CH2SiMe3)2(THF)n (Ln = Y, n = 1 (3), Ln = Er, n = 1 (4), Ln = Lu, n = 0 (5)) were prepared using alkane elimination reactions of and Ln(CH2SiMe3)3(THF)2 (Ln = Y, Er, Lu) in hexane and were isolated in 50, 70 and 75% yields respectively. The X-ray studies revealed that complexes 2-5 feature intramolecular coordination of P[double bond, length as m-dash]O groups to metal ions. The lutetium complex 5 proved to be rather stable: at 20 °C its half-life time is 1155 h, while for the yttrium analogue the half-life time was found to be 63 h. Complexes 3-5 were evaluated as precatalysts for isoprene polymerization. The systems Ln/borate/AliBu3 (Ln = 3-5, borate = [PhNHMe2][B(C6F5)4], [Ph3C][B(C6F5)4]) turned out to be highly efficient in isoprene polymerization and enable complete conversion of 1000-10,000 equivalents of monomer into polymer at 20 °C within 0.5-2.5 h affording polyisoprenes with a very high content of 1,4-cis units (up to 96.6%) and from narrow (1.49) to moderate (3.54) polydispersities. A comparative study of catalytic performance of the related bis(alkyl) yttrium complexes supported by amidinate ligands of different denticities and structures [tBuC(N-2,6iPr2C6H4)2](-), [tBuC(N-2,6-iPr2C6H4)(N-2-MeOC6H4)](-) and {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}(-) demonstrated that the introduction of a pendant donor group (2-MeOC6H4 or Ph2P(O)) into a side chain of amidinate scaffolds results in a significant increase in catalytic activity. The amidinate ligand bearing a Ph2P(O)-group provides a high isoprene polymerization rate along with excellent control over regio- and stereoselectivities and allows us to obtain polyisoprenes with a reasonable

  12. Molecular spectroscopy of uranium(IV) bis(ketimido) complexes. rare observation of resonance-enhanced raman scattering from organoactinide complexes and evidence for broken-symmetry excited states.

    PubMed

    Da Re, Ryan E; Jantunen, Kimberly C; Golden, Jeffrey T; Kiplinger, Jaqueline L; Morris, David E

    2005-01-19

    Electronic absorption and resonance-enhanced Raman spectra for ketimido (azavinylidene) complexes of tetravalent uranium, (C(5)Me(5))(2)U[-N=C(Ph)(R)](2) (R = Ph, Me, and CH(2)Ph), have been recorded. The absorption spectra exhibit four broad bands between 13 000 and 24 000 cm(-1). The highest-energy band is assigned to the ketimido-localized p( perpendicular)(N)-->pi(N=C) transition based on comparison to the spectra of (C(5)H(5))(2)Zr[-N=CPh(2)](2) and (C(5)Me(5))(2)Th[-N=CPh(2)](2). Upon excitation into any of these four absorption bands, the (C(5)Me(5))(2)U[-N=C(Ph)(R)](2) complexes exhibit resonance enhancement for several Raman bands attributable to vibrations of the ketimido ligands. Raman bands for both the symmetric and nominally asymmetric N=C stretching bands are resonantly enhanced upon excitation into the p( perpendicular)(N)-->pi(N=C) absorption bands, indicating that the excited state is localized on a single ketimido ligand. Raman excitation profiles for (C(5)Me(5))(2)U[-N=CPh(2)](2) confirm that at least one of the lower-energy electronic absorption bands (E(max) approximately 16300 cm(-1)) is a charge-transfer transition between the U(IV) center and the ketimido ligand(s). The observations of both charge-transfer transitions and resonance enhancement of Raman vibrational bands are exceedingly rare for tetravalent actinide complexes and reflect the strong bonding interactions between the uranium 5f/6d orbitals and those on the ketimido ligands. PMID:15643893

  13. Geophysical interpretation of U, Th, and rare earth element mineralization of the Bokan Mountain peralkaline granite complex, Prince of Wales Island, southeast Alaska

    USGS Publications Warehouse

    McCafferty, Anne E.; Stoeser, Douglas B.; Van Gosen, Bradley S.

    2014-01-01

    A prospectivity map for rare earth element (REE) mineralization at the Bokan Mountain peralkaline granite complex, Prince of Wales Island, southeastern Alaska, was calculated from high-resolution airborne gamma-ray data. The map displays areas with similar radioelement concentrations as those over the Dotson REE-vein-dike system, which is characterized by moderately high %K, eU, and eTh (%K, percent potassium; eU, equivalent parts per million uranium; and eTh, equivalent parts per million thorium). Gamma-ray concentrations of rocks that share a similar range as those over the Dotson zone are inferred to locate high concentrations of REE-bearing minerals. An approximately 1300-m-long prospective tract corresponds to shallowly exposed locations of the Dotson zone. Prospective areas of REE mineralization also occur in continuous swaths along the outer edge of the pluton, over known but undeveloped REE occurrences, and within discrete regions in the older Paleozoic country rocks. Detailed mineralogical examinations of samples from the Dotson zone provide a means to understand the possible causes of the airborne Th and U anomalies and their relation to REE minerals. Thorium is sited primarily in thorite. Uranium also occurs in thorite and in a complex suite of ±Ti±Nb±Y oxide minerals, which include fergusonite, polycrase, and aeschynite. These oxides, along with Y-silicates, are the chief heavy REE (HREE)-bearing minerals. Hence, the eU anomalies, in particular, may indicate other occurrences of similar HREE-enrichment. Uranium and Th chemistry along the Dotson zone showed elevated U and total REEs east of the Camp Creek fault, which suggested the potential for increased HREEs based on their association with U-oxide minerals. A uranium prospectivity map, based on signatures present over the Ross-Adams mine area, was characterized by extremely high radioelement values. Known uranium deposits were identified in the U-prospectivity map, but the largest tract occurs

  14. Ethical issues in rare diseases.

    PubMed

    Borski, Krzysztof

    2015-01-01

    Scientific, technical and medical advances continue to raise consequential ethical questions and dilemmas also in the field of rare diseases. Difficult and complex issues of medical ethics in rare diseases are presented and several different ethical problems, like those regarding inborn errors of metabolism, are discussed. PMID:26982768

  15. Rare gas isotopes and parent trace elements in ultrabasic-alkaline-carbonatite complexes, Kola Peninsula: identification of lower mantle plume component

    NASA Astrophysics Data System (ADS)

    Tolstikhin, I. N.; Kamensky, I. L.; Marty, B.; Nivin, V. A.; Vetrin, V. R.; Balaganskaya, E. G.; Ikorsky, S. V.; Gannibal, M. A.; Weiss, D.; Verhulst, A.; Demaiffe, D.

    2002-03-01

    During the Devonian magmatism (370 Ma ago) ˜20 ultrabasic-alkaline-carbonatite complexes (UACC) were formed in the Kola Peninsula (north-east of the Baltic Shield). In order to understand mantle and crust sources and processes having set these complexes, rare gases were studied in ˜300 rocks and mineral separates from 9 UACC, and concentrations of parent Li, K, U, and Th were measured in ˜70 samples. 4He/ 3He ratios in He released by fusion vary from pure radiogenic values ˜10 8 down to 6 × 10 4. The cosmogenic and extraterrestrial sources as well as the radiogenic production are unable to account for the extremely high abundances of 3He, up to 4 × 10 -9 cc/g, indicating a mantle-derived fluid in the Kola rocks. In some samples helium extracted by crushing shows quite low 4He/ 3He = 3 × 10 4, well below the mean ratio in mid ocean ridge basalts (MORB), (8.9 ± 1.0) × 10 4, indicating the contribution of 3He-rich plume component. Magnetites are principal carriers of this component. Trapped 3He is extracted from these minerals at high temperatures 1100°C to 1600°C which may correspond to decrepitation or annealing primary fluid inclusions, whereas radiogenic 4He is manly released at a temperature range of 500°C to 1200°C, probably corresponding to activation of 4He sites degraded by U, Th decay. Similar 4He/ 3He ratios were observed in Oligocene flood basalts from the Ethiopian plume. According to a paleo-plate-tectonic reconstruction, 450 Ma ago the Baltica (including the Kola Peninsula) continent drifted not far from the present-day site of that plume. It appears that both magmatic provinces could relate to one and the same deep-seated mantle source. The neon isotopic compositions confirm the occurrence of a plume component since, within a conventional 20Ne/ 22Ne versus 21Ne/ 22Ne diagram, the regression line for Kola samples is indistinguishable from those typical of plumes, such as Loihi (Hawaii). 20Ne/ 22Ne ratios (up to 12.1) correlate well with 40

  16. Solvothermal syntheses and characterizations of three new holmium selenidostannates(iv): a rare example of adamantane-like [Sn4Se10](4-) selenidostannate(iv) with lanthanide complexes.

    PubMed

    Xiao, Hong-Ping; Zhou, Jian; Wang, Xiao-Li; Zou, Hua-Hong; Zhao, Rong-Qing; Xiao, Hong

    2014-08-28

    Three new holmium selenidostannates(iv), [Ho(dap)4]2[Sn2Se6]Cl2 (, dap = diaminopropane), {[Ho(dien)2]2(μ2-OH)2}[Sn2Se6] (, dien = diethylenetriamine), and [Ho2(tepa)2(μ2-OH)2Cl2]2[Sn4Se10]·4H2O (, tepa = tetraethylenepentamine), have been solvothermally synthesized and structurally characterized. consists of two mononuclear [Ho(dap)4](3+) complex cations, one [Sn2Se6](4-) anion built up from two [SnSe4] tetrahedra sharing a common edge, and two Cl(-) ions. consists of one binuclear holmium(iii) complex {[Ho(dien)2]2(μ2-OH)2}(4+) cation and one dimeric [Sn2Se6](4-) anion. is composed of rare binuclear holmium(iii) complex [Ho2(tepa)2(μ2-OH)2Cl2](2+) cations, adamantane-like [Sn4Se10](4-) and free water molecules. Although a few chalcogenidostannates(iv) with lanthanide(iii) complex cations acting as counterions have been reported, their anions are strongly dominated by the dimeric [Sn2Se6](4-) moieties. represents a rare example of an adamantane-like [Sn4Se10](4-) selenidostannate with lanthanide complexes as counterions. The optical properties of have been investigated by UV-vis spectroscopy. PMID:24986054

  17. Not so Rare, Rare Diseases

    ERIC Educational Resources Information Center

    Waldman, H. Barry; Perlman, Steven P.; Munter, Beverly L.; Chaudhry, Ramiz A.

    2008-01-01

    A rare disease or condition is defined by federal legislation such that it: (1) affects less than 200,000 persons in the U.S.; or (2) affects more than 200,000 persons in the U.S. but for which there is no reasonable expectation that the cost of developing and making available in the U.S. a drug for such disease or condition will be recovered from…

  18. Traditional and targeted exome sequencing reveals common, rare and novel functional deleterious variants in RET signaling complex in a cohort of living US patients with urinary tract malformations

    PubMed Central

    Chatterjee, Rajshekhar; Ramos, Enrique; Hoffman, Mary; VanWinkle, Jessica; Martin, Daniel R; Davis, Thomas K; Hoshi, Masato; Hmiel, Stanley P; Beck, Anne; Hruska, Keith; Coplen, Doug; Liapis, Helen; Mitra, Robi; Druley, Todd; Austin, Paul; Jain, Sanjay

    2013-01-01

    Signaling by the glial cell line-derived neurotrophic factor (GDNF)-RET receptor tyrosine kinase and SPRY1, a RET repressor, is essential for early urinary tract development. Individual or a combination of GDNF, RET and SPRY1 mutant alleles in mice cause renal malformations reminiscent of congenital anomalies of the kidney or urinary tract (CAKUT) in humans and distinct from renal agenesis phenotype in complete GDNF or RET null mice. We sequenced GDNF, SPRY1 and RET in 122 unrelated living CAKUT patients to discover deleterious mutations that cause CAKUT. Novel or rare deleterious mutations in GDNF or RET were found in 6 unrelated patients. A family with duplicated collecting system had a novel mutation, RETR831Q, which showed markedly decreased GDNF dependent MAPK activity. Two patients with RET-G691S polymorphism harbored additional rare non-synonymous variants GDNF-R93W and RET-R982C. The patient with double RET-G691S/R982C genotype had multiple defects including renal dysplasia, megaureters and cryptorchidism. Presence of both mutations were necessary to affect RET activity. Targeted whole exome and next-generation sequencing revealed a novel deleterious mutation G443D in GFRα1, the co-receptor for RET, in this patient. Pedigree analysis indicated that the GFRα1 mutation was inherited from the unaffected mother and the RET mutations from the unaffected father. Our studies indicate that 5% of living CAKUT patients harbor deleterious rare variants or novel mutations in GDNF-GFRα1-RET pathway. We provide evidence for the coexistence of deleterious rare and common variants in genes in the same pathway as a cause of CAKUT and discovered novel phenotypes associated with the RET pathway. PMID:22729463

  19. Synthesis, characterization and cytotoxicity of rare earth metal ion complexes of N,N‧-bis-(2-thiophenecarboxaldimine)-3,3‧-diaminobenzidene, Schiff base ligand

    NASA Astrophysics Data System (ADS)

    Shakir, Mohammad; Abbasi, Ambreen; Faraz, Mohammad; Sherwani, Asif

    2015-12-01

    Lanthanide complexes of La3+, Pr3+, Nd3+, Gd3+, Er3+ of general formula [Ln2 L(H2O)4(NO3)4](NO3)2·2H2O have been synthesized from Schiff base, N,N‧-bis-(2-thiophenecarboxaldimine)-3,3‧-diaminobenzidene. The complexes were characterized by elemental analysis, molar conductance, UV-Vis, fluorescence, FT-IR,1H NMR, mass spectroscopy, EDX, SEM and thermal analysis. FT-IR spectral data suggested that ligand coordinate with metal ions through azomethine nitrogen and uncondensed amino group. Molar conductance data revealed 1:2 electrolytic nature of complexes. From the analytical data, the stoichiometry of the complexes was found to be 1:2 (ligand:metal). Thephysico-chemical data suggested eight coordination number for Ln(III)Schiffbase complexes. SEM analysis shows morphological changes in the surfaces of complexes as compared to free ligand. Thermal decomposition profiles were consistent with proposed formulations. The anticancer activity of the complexes and theSchiffbase ligand has been studied towards human cervical cancer celllines (HeLa) and human breast cancer cell lines (MCF-7) and it was found that complexes exhibited greater activity than theSchiffbase.

  20. Increased Probability of Co-Occurrence of Two Rare Diseases in Consanguineous Families and Resolution of a Complex Phenotype by Next Generation Sequencing

    PubMed Central

    Lal, Dennis; Neubauer, Bernd A.; Toliat, Mohammad R.; Altmüller, Janine; Thiele, Holger; Nürnberg, Peter; Kamrath, Clemens; Schänzer, Anne; Sander, Thomas; Hahn, Andreas; Nothnagel, Michael

    2016-01-01

    Massively parallel sequencing of whole genomes and exomes has facilitated a direct assessment of causative genetic variation, now enabling the identification of genetic factors involved in rare diseases (RD) with Mendelian inheritance patterns on an almost routine basis. Here, we describe the illustrative case of a single consanguineous family where this strategy suffered from the difficulty to distinguish between two etiologically distinct disorders, namely the co-occurrence of hereditary hypophosphatemic rickets (HRR) and congenital myopathies (CM), by their phenotypic manifestation alone. We used parametric linkage analysis, homozygosity mapping and whole exome-sequencing to identify mutations underlying HRR and CM. We also present an approximate approach for assessing the probability of co-occurrence of two unlinked recessive RD in a single family as a function of the degree of consanguinity and the frequency of the disease-causing alleles. Linkage analysis and homozygosity mapping yielded elusive results when assuming a single RD, but whole-exome sequencing helped to identify two mutations in two genes, namely SLC34A3 and SEPN1, that segregated independently in this family and that have previously been linked to two etiologically different diseases. We assess the increase in chance co-occurrence of rare diseases due to consanguinity, i.e. under circumstances that generally favor linkage mapping of recessive disease, and show that this probability can increase by several orders of magnitudes. We conclude that such potential co-occurrence represents an underestimated risk when analyzing rare or undefined diseases in consanguineous families and should be given more consideration in the clinical and genetic evaluation. PMID:26789268

  1. Increased Probability of Co-Occurrence of Two Rare Diseases in Consanguineous Families and Resolution of a Complex Phenotype by Next Generation Sequencing.

    PubMed

    Lal, Dennis; Neubauer, Bernd A; Toliat, Mohammad R; Altmüller, Janine; Thiele, Holger; Nürnberg, Peter; Kamrath, Clemens; Schänzer, Anne; Sander, Thomas; Hahn, Andreas; Nothnagel, Michael

    2016-01-01

    Massively parallel sequencing of whole genomes and exomes has facilitated a direct assessment of causative genetic variation, now enabling the identification of genetic factors involved in rare diseases (RD) with Mendelian inheritance patterns on an almost routine basis. Here, we describe the illustrative case of a single consanguineous family where this strategy suffered from the difficulty to distinguish between two etiologically distinct disorders, namely the co-occurrence of hereditary hypophosphatemic rickets (HRR) and congenital myopathies (CM), by their phenotypic manifestation alone. We used parametric linkage analysis, homozygosity mapping and whole exome-sequencing to identify mutations underlying HRR and CM. We also present an approximate approach for assessing the probability of co-occurrence of two unlinked recessive RD in a single family as a function of the degree of consanguinity and the frequency of the disease-causing alleles. Linkage analysis and homozygosity mapping yielded elusive results when assuming a single RD, but whole-exome sequencing helped to identify two mutations in two genes, namely SLC34A3 and SEPN1, that segregated independently in this family and that have previously been linked to two etiologically different diseases. We assess the increase in chance co-occurrence of rare diseases due to consanguinity, i.e. under circumstances that generally favor linkage mapping of recessive disease, and show that this probability can increase by several orders of magnitudes. We conclude that such potential co-occurrence represents an underestimated risk when analyzing rare or undefined diseases in consanguineous families and should be given more consideration in the clinical and genetic evaluation. PMID:26789268

  2. New Family of Lanthanide-Based Complexes with Different Scorpionate-Type Ligands: A Rare Case Where Dysprosium and Ytterbium Analogues Display Single-Ion-Magnet Behavior.

    PubMed

    Lannes, Anthony; Luneau, Dominique

    2015-07-20

    A new family of lanthanide complexes [Ln(Tpz)2Bpz]·xCH2Cl2 (Ln = Gd, Tb, Dy, Ho, x = 0.5; Ln = Yb, x = 1; Tpz = hydrotris(pyrazolyl)borate; Bpz = dihydrobis(pyrazolyl)borate) has been synthesized. Those complexes have been characterized by single-crystal X-ray diffraction, and the magnetic properties have been investigated. Both dysprosium and ytterbium analogues display single-ion-magnet behavior, despite the difference in their spatial distribution of 4f electronic charges. Theoretical calculations with crystal field parameters have been carried out to gain better insight of the relaxation pathways that may be involved in those two complexes. PMID:26132295

  3. Synthesis of mono-amidinate-ligated rare-earth-metal bis(silylamide) complexes and their reactivity with [Ph3C][B(C6F5)4], AlMe3 and isoprene.

    PubMed

    Luo, Yunjie; Lei, Yinlin; Fan, Shimin; Wang, Yibin; Chen, Jue

    2013-03-21

    Amine elimination of rare-earth-metal tris(silylamide) complexes Ln[N(SiHMe(2))(2)](3)(THF)(x) (Ln = Sc, x = 1; Ln = Y, x = 2) with 1 equiv. of the amidines [PhC(N-2,6-R(2)C(6)H(3))(2)]H afforded a series of neutral mono(amidinate) rare-earth-metal bis(silylamide) complexes [PhC(N-2,6-R(2)C(6)H(3))(2)]Ln[N(SiHMe(2))(2)](2)(THF)(y) (R = Me, Ln = Sc, y = 0 (1); R = Me, Ln = Y, y = 1 (2); R = (i)Pr, Ln = Y, y = 1 (3)). Treatment of 1-3 with 1 equiv. of [Ph(3)C][B(C(6)F(5))(4)] in THF generated the corresponding cationic amidinate rare-earth-metal mono(silylamide) complexes [{PhC(N-2,6-R(2)C(6)H(3))(2)}Ln{N(SiHMe(2))(2)}(THF)(3)][B(C(6)F(5))(4)] (R = Me, Ln = Sc (4), Y (5); R = (i)Pr, Ln = Y (6)). When 1-3 were first activated with 1 equiv. of [Ph(3)C][B(C(6)F(5))(4)] in toluene, then treatment with THF gave the unexpected cationic amidinate rare-earth-metal amide complexes [{PhC(N-2,6-R(2)C(6)H(3))(2)}LnN{SiHMe(2)}{SiMe(2)N(SiHMe(2))(2)}(THF)(n)][B(C(6)F(5))(4)] (R = Me, Ln = Sc, n = 2 (7); R = Me, Ln = Y, n = 4 (8); R = (i)Pr, Ln = Y, n = 2 (9)). The reaction of 1-3 with excess AlMe(3) produced the heterometallic Ln/Al methyl complexes [PhC(N-2,6-R(2)C(6)H(3))(2)]Ln[(μ-Me)(2)AlMe(2)](2) (R = Me, Ln = Sc (10), Y (11); R = (i)Pr, Ln = Y (12)). All these complexes were well-characterized by elemental analysis, NMR spectroscopy and FT-IR spectroscopy. 2, 6 and 11 were further structurally authenticated by X-ray crystallography. The binary catalyst system of 1/[Ph(3)C][B(C(6)F(5))(4)] in toluene showed activity toward 3,4-selective polymerization of isoprene, whilst the tertiary catalyst systems of 1-3/[Ph(3)C][B(C(6)F(5))(4)]/AlMe(3) were highly active for cis-1,4-selective polymerization of isoprene. PMID:23340682

  4. High fluorescence emission of carboxylic acid functionalized polystyrene/BaTiO{sub 3} nanocomposites and rare earth metal complexes: Preparation and characterization

    SciTech Connect

    Cao, X. T.; Showkat, A. M.; Wang, Z.; Lim, K. T.

    2015-03-30

    Noble fluorescence nanocomposite compound based on barium titanate nanoparticles (BTO), polystyrene (PSt), and terbium ion (Tb{sup 3+}) was synthesized by a combination of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, Friedel-Crafts alkylation reaction and coordinate chemistry. Initially, a modification of surface of BTO was conducted by an exchange process with S-benzyl S’-trimethoxysilylpropyltrithiocarbonate to create macro-initiator for polymerization of styrene. Subsequently, aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-COOH) was generated by substitution reaction between 4-(Chloromethyl) benzoic acid and PSt chains. The coordination of the nanohybrids with Tb{sup 3+} ions afforded fluorescent Tb{sup 3+} tagged aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-Tb{sup 3+}) complexes. Structure, morphology, and fluorescence properties of nanohybrid complexes were investigated by respective physical and spectral studies. FT-IR and SEM analyses confirmed the formation of BTO-g-PSt-Tb{sup 3+}nanohybrids. Furthermore, TGA profiles demonstrated the grafting of aryl carboxylic acid functionalized polystyrene on BTO surface. Optical properties of BTO-g-PSt-Tb{sup 3+} complexes were investigated by fluorescence spectroscopy.

  5. High fluorescence emission of carboxylic acid functionalized polystyrene/BaTiO3 nanocomposites and rare earth metal complexes: Preparation and characterization

    NASA Astrophysics Data System (ADS)

    Cao, X. T.; Showkat, A. M.; Wang, Z.; Lim, K. T.

    2015-03-01

    Noble fluorescence nanocomposite compound based on barium titanate nanoparticles (BTO), polystyrene (PSt), and terbium ion (Tb3+) was synthesized by a combination of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, Friedel-Crafts alkylation reaction and coordinate chemistry. Initially, a modification of surface of BTO was conducted by an exchange process with S-benzyl S'-trimethoxysilylpropyltrithiocarbonate to create macro-initiator for polymerization of styrene. Subsequently, aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-COOH) was generated by substitution reaction between 4-(Chloromethyl) benzoic acid and PSt chains. The coordination of the nanohybrids with Tb3+ ions afforded fluorescent Tb3+ tagged aryl carboxylic acid functionalized polystyrene grafted barium titanate (BTO-g-PSt-Tb3+) complexes. Structure, morphology, and fluorescence properties of nanohybrid complexes were investigated by respective physical and spectral studies. FT-IR and SEM analyses confirmed the formation of BTO-g-PSt-Tb3+nanohybrids. Furthermore, TGA profiles demonstrated the grafting of aryl carboxylic acid functionalized polystyrene on BTO surface. Optical properties of BTO-g-PSt-Tb3+ complexes were investigated by fluorescence spectroscopy.

  6. Synthesis and characterization of dinuclear rare-earth complexes supported by amine-bridged bis(phenolate) ligands and their catalytic activity for the ring-opening polymerization of l-lactide.

    PubMed

    Duan, Yu-Lai; He, Jia-Xuan; Wang, Wei; Zhou, Jing-Jing; Huang, Yong; Yang, Ying

    2016-06-28

    Reactions of amine-bridged bis(phenolate) protio-ligands N,N-bis(3,5-di-tert-butyl-2-hydroxybenzyl)aminoacetic acid (L(1)-H3) and N,N-bis[3,5-bis(α,α'-dimethylbenzyl)-2-hydroxybenzyl]aminoacetic acid (L(2)-H3), with 1 equiv. M[N(SiMe3)2]3 (M = La, Nd, Sm, Gd, Y) in THF at room temperature yielded the neutral rare-earth complexes [M2(L)2(THF)4] (L = L(1), M = La (), Nd (), Sm (), Gd (), Y (); L = L(2), M = La (), Nd (), Sm (), Gd (), Y ()). All of these complexes were characterized by single-crystal X-ray diffraction, elemental analysis and in the case of yttrium and lanthanum complexes, (1)H NMR spectroscopy. The molecular structure of revealed dinuclear species in which the eight-coordinate lanthanum centers were bonded to two oxygen atoms of two THF molecules, to three oxygen atoms and one nitrogen atom of one L(1) ligand, and two oxygen atoms of the carboxyl group of another. Complexes were also dinuclear species containing seven-coordinate metal centers similar to , albeit with bonding to one rather than two carboxyl group oxygens of another ligand. Further treatment of with excess benzyl alcohol provided dinuclear complex [La2(L(1))2(BnOH)6] (), in which each lanthanum ion is eight-coordinate, bonded to three oxygen atoms and one nitrogen atom of one ligand, three oxygen atoms of three BnOH molecules, as well as one oxygen atom of bridging carboxyl group of the other ligand. In the presence of BnOH, complexes efficiently catalyzed the ring-opening polymerization of l-lactide in a controlled manner and gave polymers with relatively narrow molecular weight distributions. The kinetic and mechanistic studies associated with the ROP of l-lactide using /BnOH initiating system have been performed. PMID:27294827

  7. Different Adsorption Behavior of Rare Earth and Metallic Ion Complexes on Langmuir Mono layers Probed by Sum-Frequency Generation Spectroscopy

    SciTech Connect

    Song, Woongmo; Vaknin, David; Kim, Doseok

    2013-02-25

    Adsorption behavior of counterions under a Langmuir monolayer was investigated by sum-frequency generation (SFG) spectroscopy. By comparing SFG spectra of arachidic acid (AA) Langmuir monolayer/water interface with and without added salt, it was found that the simple trivalent cation La3+ adsorbed on AA monolayer only when the carboxylic headgroups are charged (deprotonated), implying that counterion adsorption is induced by Coulomb interaction. On the other hand, metal hydroxide complex Fe(OH)3 adsorbed even on a charge-neutral AA monolayer, indicating that the adsorption of iron hydroxide is due to chemical interaction such as covalent or hydrogen bonding to the headgroup of the molecules at the monolayer.

  8. Rare Kaon Decays, KEK experiment E391 and E14 at the Japan Physics and Accelerator Research Complex (J-PARC)

    SciTech Connect

    Wah, Yau Wai

    2012-12-06

    The goal of the J-PARC neutral kaon experiment (E14/KOTO) is to discover and measure the rate of the kaon rare decay to pi-zero and two neutrinos. This flavor changing neutral current decay proceeds through second-order weak interactions. Other, as yet undiscovered particles, which can mediate the decay could provide an enhancement (or depletion) to the branching ratio which in the Standard Model is accurately predicted within a few percent to be 2.8x10-11. The experiment is designed to observe more than 100 events at the Standard Model branching. It is a follow-up of the KEK E391a experiment and has stage-2 approval by J-PARC PAC in 2007. E14/KOTO has collaborators from Japan (Kyoto, Osaka, Yamagata, Saga), US (Arizona State, Chicago, Michigan Ann Arbor), Taiwan (National Taiwan), Korea, and Russia (Dubna). The experiment exploits the 300kW 30-50 GeV proton delivery of the J-PARC accelerator with a hermetic high acceptance detector with a fine grained Cesium Iodide (CsI) crystal calorimeter, and state of the art electronic front end and data acquisition system. With the recovery of the tsunami disaster on March 11th 2011, E14 is scheduled to start collecting data in December 2012. During the detector construction phase, Chicago focuses on the front end electronics readout of the entire detector system, particularly the CsI calorimeter. The CsI crystals together with its photomultipliers were previously used at the Fermilab KTeV experiment (E832/E799), and were loaned to E14 via this Chicago DOE support. The new readout electronics includes an innovative 10-pole pulse-shaping technique coupled with high speed digitization (14-bit 125MHz and 12-bit 500MHz). This new instrument enables us to measure both energy and timing, particularly with timing resolution better than 100 psec. Besides the cost saving by elimination of the standard time to digital converters, it is now possible to measure the momenta of the final state photons for additional background suppression

  9. Rare-earth metal bis(silylamide) complexes supported by mono-dentate arylamido ligand: synthesis, reactivity, and catalyst precursors in living cis-1,4-selective polymerization of isoprene.

    PubMed

    Shi, Liqin; Su, Qi; Chen, Jue; Li, Xiaonian; Luo, Yunjie

    2016-01-28

    The salt metathesis reaction of LnCl3 with 1 equivalent of arylamido lithium [2,6-(i)Pr2C6H3N(SiMe3)]Li followed by addition of 2 equivalents of LiN(SiHMe2)2 in THF at room temperature obtained neutral mono-arylamido-ligated rare-earth metal bis(silylamide) complexes [2,6-(i)Pr2C6H3N(SiMe3)]Ln[N(SiHMe2)2]2(THF) (Ln = Y (), Lu (), La ()) in good isolated yields. Treatment of with excess AlMe3 produced the mono(arylamido) Ln/Al heterotrinuclear methyl complexes [2,6-(i)Pr2C6H3N(SiMe3)]Ln[(μ-Me)2AlMe2]2 (Ln = Y (), Lu (), La ()) via amide-alkyl exchange. All these complexes were well-characterized by elemental analysis, NMR spectroscopy and FT-IR spectroscopy. , and were further structurally authenticated by X-ray crystallography. In the presence of [Ph3C][B(C6F5)4] and Al(i)Bu3, were highly active for cis-1,4-selective polymerization of isoprene, whereas /[Ph3C][B(C6F5)4]/Al(i)Bu3 promoted the polymerization in a living fashion. PMID:26674733

  10. Novel light-conversion hybrids of SBA-16 functionalized with rare earth (Eu3+, Nd3+, Yb3+) complexes of modified 2-methyl-9-hydroxyphenalenone and 1,10-phenanthroline

    NASA Astrophysics Data System (ADS)

    Gu, Yan-Jing; Yan, Bing; Qiao, Xiao-Fei

    2013-03-01

    Novel rare earth complex-functionalized mesoporous SBA-16-type hybrid materials are synthesized by the co-condensation of modified 2-methyl-9-hydroxyphenalenone (MHPOSi), from modified 3-(triethoxysilyl)-propyl isocyanate (TEPIC), and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as a template. These inorganic-organic mesoporous hybrids are characterized by FT-IR spectra, small-angle X-ray diffraction (SAXRD), N2 adsorption-desorption measurements, thermal analysis and spectroscopy. Their photophysical properties, which show novel light conversion properties, are discussed in detail. The Eu3+ hybrid system shows ultraviolet excitation and visible emission, and the Nd+ and Yb3+ hybrids exhibit visible excitation and NIR emission.

  11. Hybrid materials of SBA-16 functionalized by rare earth (Eu 3+, Tb 3+) complexes of modified β-diketone (TTA and DBM): Covalently bonding assembly and photophysical properties

    NASA Astrophysics Data System (ADS)

    Li, Yajuan; Yan, Bing; Li, Ying

    2010-04-01

    Novel mesoporous SBA-16 type of hybrids TTA-S16 and DBM-S16 were synthesized by co-condensation of modified β-diketone (TTA-Si and DBM-Si, DBM=1,3-diphenyl-1,3- propanepione, TTA=2-thenoyltrifluoroacetone) and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as template, which were confirmed by FTIR, XRD, 29Si CP-MAS NMR, and N 2 adsorption measurements. Novel organic-inorganic mesoporous luminescent hybrid containing RE3+ (Eu 3+, Tb 3+) complexes covalently attached to the functionalized ordered mesoporous SBA-16 (TTA-S16 and DBM-S16), which were designated as bpy- RE-TTA-S16 and bpy- RE-DBM-S16, were obtained by sol-gel process. The luminescence properties of these resulting materials were characterized in detail, and the results reveal that mesoporous hybrid material bpy-Eu-TTA-S16 present stronger luminescent intensities, longer lifetimes, and higher luminescent quantum efficiencies than the corresponding DBM-containing materials bpy-Eu-DBM-S16, while bpy-Tb-DBM-S16 exhibit the stronger characteristic emission of Tb 3+ and longer lifetime than the corresponding TTA-containing materials bpy-Tb-TTA-S16.

  12. RARE DISEASES LIST

    EPA Science Inventory

    The rare disease list includes rare diseases and conditions for which information requests have been made to the Office of Rare Diseases. A rare disease is defined as a disease or condition for which there are fewer than 200,000 affected persons alive in the United States. The Of...

  13. The Lombardy Rare Donor Programme

    PubMed Central

    Revelli, Nicoletta; Villa, Maria Antonietta; Paccapelo, Cinzia; Manera, Maria Cristina; Rebulla, Paolo; Migliaccio, Anna Rita; Marconi, Maurizio

    2014-01-01

    Background In 2005, the government of Lombardy, an Italian region with an ethnically varied population of approximately 9.8 million inhabitants including 250,000 blood donors, founded the Lombardy Rare Donor Programme, a regional network of 15 blood transfusion departments coordinated by the Immunohaematology Reference Laboratory of the Ca’ Granda Ospedale Maggiore Policlinico in Milan. During 2005 to 2012, Lombardy funded LORD-P with 14.1 million euros. Materials and methods During 2005–2012 the Lombardy Rare Donor Programme members developed a registry of blood donors and a bank of red blood cell units with either rare blood group phenotypes or IgA deficiency. To do this, the Immunohaematology Reference Laboratory performed extensive serological and molecular red blood cell typing in 59,738 group O or A, Rh CCDee, ccdee, ccDEE, ccDee, K− or k− donors aged 18–55 with a record of two or more blood donations, including both Caucasians and ethnic minorities. In parallel, the Immunohaematology Reference Laboratory implemented a 24/7 service of consultation, testing and distribution of rare units for anticipated or emergent transfusion needs in patients developing complex red blood cell alloimmunisation and lacking local compatible red blood cell or showing IgA deficiency. Results Red blood cell typing identified 8,747, 538 and 33 donors rare for a combination of common antigens, negative for high-frequency antigens and with a rare Rh phenotype, respectively. In June 2012, the Lombardy Rare Donor Programme frozen inventory included 1,157 red blood cell units. From March 2010 to June 2012 one IgA-deficient donor was detected among 1,941 screened donors and IgA deficiency was confirmed in four previously identified donors. From 2005 to June 2012, the Immunohaematology Reference Laboratory provided 281 complex red blood cell alloimmunisation consultations and distributed 8,008 Lombardy Rare Donor Programme red blood cell units within and outside the region

  14. Rare Disorders and Diseases

    ERIC Educational Resources Information Center

    Umlauf, Mary; Monaco, Jana; FitzZaland, Mary; FitzZaland, Richard; Novitsky, Scott

    2008-01-01

    According to the National Organization for Rare Disorders (NORD), a rare or "orphan" disease affects fewer than 200,000 people in the United States. There are more than 6,000 rare disorders that, taken together, affect approximately 25 million Americans. "Exceptional Parent" ("EP") recognizes that when a disorder affects a child or adult, it…

  15. Intracomplex {pi}-{pi} stacking interaction between adjacent phenanthroline molecules in complexes with rare-earth nitrates: Crystal and molecular structures of bis(1,10-Phenanthroline)trinitratoytterbium and bis(1,10-Phenanthroline)trinitratolanthanum

    SciTech Connect

    Sadikov, G. G. Antsyshkina, A. S.; Rodnikova, M. N.; Solonina, I. A.

    2009-01-15

    Crystals of the compounds Yb(NO{sub 3}){sub 3}(Phen){sub 2} and La(NO{sub 3}){sub 3}(Phen){sub 2} (Phen = 1,10-phenanthroline) are investigated using X-ray diffraction. It is established that there exist two different crystalline modifications: the main modification (phase 1) is characteristic of all members of the isostructural series, and the second modification (phase 2) is observed only for the Eu, Er, and Yb elements. It is assumed that the stability and universality of main phase 1 are associated with the occurrence of the nonbonded {pi}-{pi} stacking interactions between the adjacent phenanthroline ligands in the complexes. The indication of the interactions is a distortion of the planar shape of the Phen molecule (the folding of the metallocycle along the N-N line with a folding angle of 11{sup o}-13{sup o} and its 'boomerang' distortion). The assumption regarding the {pi}-{pi} stacking interaction is very consistent with the shape of the ellipsoids of atomic thermal vibrations, as well as with the data obtained from thermography and IR spectroscopy. An analysis of the structures of a number of rare-earth compounds has demonstrated that the intracomplex {pi}-{pi} stacking interactions directly contribute to the formation of supramolecular associates in the crystals, such as molecular dimers, supramolecules, chain and layered ensembles, and framework systems.

  16. [Rare diseases from a life insurance perspective].

    PubMed

    Senn, A; Filzmaier, K

    2015-12-01

    A rare disease is defined as a disease that affects a maximum of 5 in 10,000 people. As of today there are roughly 7000 different rare diseases known. On account of this one can say that "rare diseases are rare, but people affected by them are common". For Germany this amounts to: 4 million people that are affected by a rare disease. Diagnosis, therapeutic options and prognosis have substantially improved for some of the rare diseases. Besides the general medical advances--especially in the area of genetics--this is also due to networking and sharing information by so-called Centres of Competence on a national and international scale. This results in a better medical care for the corresponding group of patients. Against this backdrop, the number of people applying for life assurance who are suffering from a complex or rare disease has risen steadily in the last years. Due to the scarce availability of data regarding long-term prognosis of many rare diseases, a biomathematical, medical and actuarial expertise on the part of the insurer is necessary in order to adequately assess the risk of mortality and morbidity. Furthermore there is quite a focus on the issue of rare diseases from not only politics but society as well. Therefore evidence based medical assessment by insurers is especially important in this group of applicants--thinking of legal compliance and reputational risk. PMID:26775306

  17. A rare case of a three way complex variant positive Philadelphia translocation involving chromosome (9;11;22)(q34;p15;q11) in chronic myeloid leukemia: A case report

    PubMed Central

    Asif, Muhammad; Hussain, Abrar; Rasool, Mahmood

    2016-01-01

    The t(9;22)(q34;q11) translocation is present in 90–95% of patients with chronic myeloid leukemia (CML). Variant complex translocations have been observed in 5–8% of CML patients, in which a third chromosome other than (9;22) is involved. Imatinib mesylate is the first line breakpoint cluster region-Abelson gene (BCR/ABL)-targeted oral therapy for CML, and may produce a complete response in 70–80% of CML patients in the chronic phase. In the present study, a bone marrow sample was used for conventional cytogenetic analysis, and the fluorescence in situ hybridization (FISH) test was used for BCR/ABL gene detection. A hematological analysis was also performed to determine the white blood cell (WBC) count, red blood cell count, hemoglobin levels, packed and mean cell volumes, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and platelet values of the patient. The hematological analysis of the patient indicated the increased WBC of 186.5×103 cells/µl, and decreased hemoglobin levels of 11.1 g/dl. The FISH test revealed that 67% cells demonstrated BCR/ABL gene translocation. The patient was treated with 400 mg imatinib mesylate daily, and was monitored at various intervals over a 6-month period. The present study reports the rare case of a patient that demonstrates a three-way Philadelphia chromosome-positive translocation involving 46XY,t(9;11;22)(q34;p15;q11)[10], alongside CML in the chronic phase. The translocation was analyzed using cytogenetic and FISH tests. PMID:27602125

  18. Rare Parotid Gland Diseases.

    PubMed

    Sanan, Akshay; Cognetti, David M

    2016-04-01

    The differential diagnosis for "rare" parotid gland diseases is broad and encompasses infectious, neoplastic, autoimmune, metabolic, and iatrogenic etiologies. The body of knowledge of parotid gland diseases has grown owing to advances in imaging and pathologic analysis and molecular technology. This article reviews rare parotid diseases, discussing the respective disease's clinical presentation, diagnosis, imaging, pathogenesis, treatment, and prognosis. PMID:26902981

  19. Rare earth element scavenging in seawater

    NASA Astrophysics Data System (ADS)

    Byrne, Robert H.; Kim, Ki-Hyun

    1990-10-01

    Examinations of rare earth element (REE) adsorption in seawater, using a variety of surface-types, indicated that, for most surfaces, light rare earth elements (LREEs) are preferentially adsorbed compared to the heavy rare earths (HREEs). Exceptions to this behavior were observed only for silica phases (glass surfaces, acid-cleaned diatomaceous earth, and synthetic SiO 2). The affinity of the rare earths for surfaces can be strongly affected by thin organic coatings. Glass surfaces which acquired an organic coating through immersion in Tampa Bay exhibited adsorptive behavior typical of organic-rich, rather than glass, surfaces. Models of rare earth distributions between seawater and carboxylate-rich surfaces indicate that scavenging processes which involve such surfaces should exhibit a strong dependence on pH and carbonate complexation. Scavenging models involving carboxylate surfaces produce relative REE abundance patterns in good general agreement with observed shale-normalized REE abundances in seawater. Scavenging by carboxylate-rich surfaces should produce HREE enrichments in seawater relative to the LREEs and may produce enrichments of lanthanum relative to its immediate trivalent neighbors. Due to the origin of distribution coefficients as a difference between REE solution complexation (which increases strongly with atomic number) and surface complexation (which apparently also increases with atomic number) the relative solution abundance patterns of the REEs produced by scavenging reactions can be quite complex.

  20. Identifying rare events in rare diseases.

    PubMed

    Attiyeh, Edward F; Maris, John M

    2015-04-15

    Utilizing genomic signatures from diagnostic tumor samples to forecast clinical behavior and response to therapy has long been a goal, and we are now poised to further refine how we can identify the relatively rare patients with aggressive neuroblastoma masquerading as patients with a more benign form of the disease. Clin Cancer Res; 21(8); 1782-5. ©2014 AACR. See related article by Oberthuer et al., p. 1904. PMID:25424848

  1. A rare opportunity beckons

    SciTech Connect

    Gschneidner, K

    2011-02-01

    There is a great deal of uncertainty for the future of rare-earth production. Rare-earths are a collection of 17 chemical elements in the periodic table, which include scandium and yttrium as well as the 15 lanthanides, such as dysprosium and ytterbium. China has a stranglehold on today's rare-earth market, which was worth about $3bn in 2010, with the country accounting for about 95% of worldwide production. Yet China's future actions can only be guessed at best. In September it halted shipments of rare-earth elements to Japan over a diplomatic spat concerning the detention of a Chinese trawler captain. Although the ban was later lifted, the episode raised concerns around the world about China's rare-earth monopoly and its use in diplomacy. China has already warned that it will not export any rare-earth material in the coming years as it expects its own consumption of rare-earth metals to increase. The country has introduced export taxes as well as production and export quotas, and also refused to grant any new rare-earth mining licences. Furthermore, because its reserves are limited and China's internal markets are growing so rapidly, the country has suggested it will no longer export products that require rare-earth elements, especially those that need heavy rare-earth elements, such as terbium and dysprosium. China's actions have led to huge rises in the cost of rare-earth materials and products. Dysprosium oxide, for example, has shot up from $36 per kilogram in 2005 to a massive $305 per kilogram by late last year. This could have a huge impact on much of today's electronics industry, given that rare-earth elements are ubiquitous in electric motors, computers, batteries, liquid-crystal displays (LCDs) and mobile phones. Neodymium-iron-boron permanent magnets, for example, are used as computer spindle drives. The question is: what can be done to ensure that China's dominance of the rare-earth industry does not affect the military and energy security of the US

  2. Collecting rare diseases

    PubMed Central

    Ekins, Sean

    2014-01-01

    This editorial introduces the F1000Research rare disease collection. It is common knowledge that for new treatments to be successful there has to be a partnership between the many interested parties such as the patient, advocate, disease foundations, the academic scientists, venture funding organizations, biotech companies, pharmaceutical companies, NIH, and the FDA. Our intention is to provide a forum for discussion and dissemination of any rare disease related topics that will advance scientific understanding and progress to treatments. PMID:25580231

  3. Medical rare book provenance.

    PubMed Central

    Overmier, J A; Sentz, L

    1987-01-01

    Provenance is defined as the record of a book's ownership history. Its value and uses are explored. A survey of provenance practices in medical school rare book libraries found that only 21% of the reporting libraries maintain this important file. Examples of the uses and value of a provenance file in a medical rare book collection are presented. Decisions necessary to institute and maintain such a file are outlined and discussed. PMID:3828606

  4. Rare Diseases Clinical Research Network

    MedlinePlus

    ... RDCRN? Aims of the Rare Diseases Clinical Research Network Contact Us RDCRN Members Login Accessibility Disclaimer The Rare Diseases Clinical Research Network is an initiative of the Office of Rare ...

  5. Endangered Species: Wild & Rare.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1987-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Endangered Species: Wild and Rare." Contents are organized into the following…

  6. CLUSTERING OF RARE EVENTS

    EPA Science Inventory

    The clustering of cases of a rare disease is considered. The number of events observed for each unit is assumed to have a Poisson distribution, the mean of which depends upon the population size and the cluster membership of that unit. Here a cluster consists of those units that ...

  7. Channel Islands rare plants

    USGS Publications Warehouse

    McEachern, K.

    1999-01-01

    Database contains information on 65 rare plant taxa on six islands from archive searches and field surveys, including population location, size and extent 1920-1999, population and habitat conditions, census data, phenological information, associated species. USGS-BRD, Channel Islands Field Station, Ventura, CA.

  8. The rare bacterial biosphere.

    PubMed

    Pedrós-Alió, Carlos

    2012-01-01

    All communities are dominated by a few species that account for most of the biomass and carbon cycling. On the other hand, a large number of species are represented by only a few individuals. In the case of bacteria, these rare species were until recently invisible. Owing to their low numbers, conventional molecular techniques could not retrieve them. Isolation in pure culture was the only way to identify some of them, but current culturing techniques are unable to isolate most of the bacteria in nature. The recent development of fast and cheap high-throughput sequencing has begun to allow access to the rare species. In the case of bacteria, the exploration of this rare biosphere has several points of interest. First, it will eventually produce a reasonable estimate of the total number of bacterial taxa in the oceans; right now, we do not even know the right order of magnitude. Second, it will answer the question of whether "everything is everywhere." Third, it will require hypothesizing and testing the ecological mechanisms that allow subsistence of many species in low numbers. And fourth, it will open an avenue of research into the immense reserve of genes with potential applications hidden in the rare biosphere. PMID:22457983

  9. Rare lung cancers.

    PubMed

    2015-12-01

    There are several different kinds of lung cancer, often referred to as lung cancer subtypes. Some of these occur more often than others. In this factsheet we will specifically look at the subtypes of cancers that do not happen very often and are considered 'rare'. PMID:27066129

  10. Rare Copy Number Variants

    PubMed Central

    Grozeva, Detelina; Kirov, George; Ivanov, Dobril; Jones, Ian R.; Jones, Lisa; Green, Elaine K.; St Clair, David M.; Young, Allan H.; Ferrier, Nicol; Farmer, Anne E.; McGuffin, Peter; Holmans, Peter A.; Owen, Michael J.; O’Donovan, Michael C.; Craddock, Nick

    2015-01-01

    Context Recent studies suggest that copy number variation in the human genome is extensive and may play an important role in susceptibility to disease, including neuropsychiatric disorders such as schizophrenia and autism. The possible involvement of copy number variants (CNVs) in bipolar disorder has received little attention to date. Objectives To determine whether large (>100 000 base pairs) and rare (found in <1% of the population) CNVs are associated with susceptibility to bipolar disorder and to compare with findings in schizophrenia. Design A genome-wide survey of large, rare CNVs in a case-control sample using a high-density microarray. Setting The Wellcome Trust Case Control Consortium. Participants There were 1697 cases of bipolar disorder and 2806 nonpsychiatric controls. All participants were white UK residents. Main Outcome Measures Overall load of CNVs and presence of rare CNVs. Results The burden of CNVs in bipolar disorder was not increased compared with controls and was significantly less than in schizophrenia cases. The CNVs previously implicated in the etiology of schizophrenia were not more common in cases with bipolar disorder. Conclusions Schizophrenia and bipolar disorder differ with respect to CNV burden in general and association with specific CNVs in particular. Our data are consistent with the possibility that possession of large, rare deletions may modify the phenotype in those at risk of psychosis: those possessing such events are more likely to be diagnosed as having schizophrenia, and those without them are more likely to be diagnosed as having bipolar disorder. PMID:20368508

  11. Rare Isotope Accelerators

    NASA Astrophysics Data System (ADS)

    Savard, Guy

    2002-04-01

    The next frontier for low-energy nuclear physics involves experimentation with accelerated beams of short-lived radioactive isotopes. A new facility, the Rare Isotope Accelerator (RIA), is proposed to produce large amount of these rare isotopes and post-accelerate them to energies relevant for studies in nuclear physics, astrophysics and the study of fundamental interactions at low energy. The basic science motivation for this facility will be introduced. The general facility layout, from the 400 kW heavy-ion superconducting linac used for production of the required isotopes to the novel production and extraction schemes and the highly efficient post-accelerator, will be presented. Special emphasis will be put on a number of technical breakthroughs and recent R&D results that enable this new facility.

  12. Rare causes of osteoporosis

    PubMed Central

    Marcucci, Gemma; Brandi, Maria Luisa

    2015-01-01

    Summary Osteoporosis is a metabolic bone disease characterized by loss of bone mass and strength, resulting in increased risk of fractures. It is classically divided into primary (post-menopausal or senile), secondary and idiopathic forms. There are many rare diseases, that cause directly or indirectly osteoporosis. The identification and classification of most of these rare causes of osteoporosis is crucial for the specialists in endocrinology and not, in order to prevent this bone complication and to provide for an early therapy. Several pathogenic mechanisms are involved, including various aspects of bone metabolism such as: decreased bone formation, increased bone resorption, altered calcium, phosphorus and/or vitamin D homeostasis, and abnormal collagen synthesis. In this review, less common forms of primary and secondary osteoporosis are described, specifying, if applicable: genetic causes, epidemiology, clinical features, and pathogenic mechanisms causing osteoporosis. A greater awareness of all rare causes of osteoporosis could reduce the number of cases classified as idiopathic osteoporosis and allow the introduction of appropriate and timely treatments. PMID:26604941

  13. Rare B Decays

    SciTech Connect

    Jackson, P.D.; /Victoria U.

    2006-02-24

    Recent results from Belle and BaBar on rare B decays involving flavor-changing neutral currents or purely leptonic final states are presented. Measurements of the CP asymmetries in B {yields} K*{gamma} and b {yields} s{gamma} are reported. Also reported are updated limits on B{sup +} {yields} K{sup +}{nu}{bar {nu}}, B{sup +} {yields} {tau}{sup +}{nu}, B{sup +} {yields} {mu}{sup +}{nu} and the recent measurement of B {yields} X{sub s}{ell}{sup +}{ell}{sup -}.

  14. Ames Lab 101: Rare Earths

    SciTech Connect

    Gschneidner, Karl

    2010-01-01

    "Mr. Rare Earth," Ames Laboratory scientist Karl Gschneidner Jr., explains the importance of rare-earth materials in many of the technologies we use today -- ranging from computers to hybrid cars to wind turbines. Gschneidner is a world renowned rare-earths expert at the U.S. Department of Energy's Ames Laboratory.

  15. Ames Lab 101: Rare Earths

    ScienceCinema

    Gschneidner, Karl

    2012-08-29

    "Mr. Rare Earth," Ames Laboratory scientist Karl Gschneidner Jr., explains the importance of rare-earth materials in many of the technologies we use today -- ranging from computers to hybrid cars to wind turbines. Gschneidner is a world renowned rare-earths expert at the U.S. Department of Energy's Ames Laboratory.

  16. The structure and stability of aqueous rare-earth elements in hydrothermal fluids: New results on neodymium(III) aqua and chloroaqua complexes in aqueous solutions to 500 °C and 520 MPa

    USGS Publications Warehouse

    Mayanovic, Robert A.; Anderson, Alan J.; Bassett, William A.; Chou, I.-Ming

    2009-01-01

    X-ray absorption spectroscopy (XAS) measurements were made at the Nd L3-edge on neodymium(III) aqua and chloroaqua complexes in low pH aqueous solutions from 25 to 500????C and up to 520??MPa. Analysis of the extended X-ray absorption fine structure of the XAS spectra measured from a 0.07??m Nd/0.16??m HNO3 aqueous solution reveals a contraction of the Nd-O distance of the Nd3+ aqua ion at a uniform rate of ~ 0.013????/100????C and a uniform reduction of the number of coordinated H2O molecules from 10.0 ?? 0.9 to 7.4 ?? 0.9 over the range from 25 to 500????C and up to 370??MPa. The rate of reduction of the first-shell water molecules with temperature for Nd3+ (26%) is intermediate between the rate for the Gd3+ aqua ion (22% from 25 to 500????C) and the rates for the Eu3+ (29% from 25 to 400????C) and the Yb3+ aqua ions (42% from 25 to 500????C) indicating an intermediate stability of the Nd3+ aqua ion consistent with the tetrad effect. Nd L3-edge XAS measurements of 0.05??m NdCl3 aqueous solution at 25 to 500????C and up to 520??MPa show that stepwise inner-sphere complexes most likely of the type Nd(H2O)?? - nCln+3 - n occur in the solution at elevated temperatures, where ?? ??? 9 at 150????C decreasing to ~ 6 at 500????C and the number of chloride ions (n) of the chloroaqua complexes increases uniformly with temperature from 1.2 ?? 0.2 to 2.0 ?? 0.2 in the solution upon increase of temperature from 150 to 500????C. Conversely, the number of H2O ligands of Nd(H2O)?? - nCln+3 - n complexes is uniformly reduced with temperature from 7.5 ?? 0.8 to 3.7 ?? 0.3 in the aqueous solution, in the same temperature range. These data show greater stability of neodymium(III) than gadolinium(III) and ytterbium(III) chloride complexes in low pH aqueous solutions at elevated temperatures. Our data suggest a greater stability of aqueous light REE than that of heavy REE chloride complexes in low pH fluids at elevated temperatures consistent with REE analysis of fluids from deep

  17. Rare Upper Airway Anomalies.

    PubMed

    Windsor, Alanna; Clemmens, Clarice; Jacobs, Ian N

    2016-01-01

    A broad spectrum of congenital upper airway anomalies can occur as a result of errors during embryologic development. In this review, we will describe the clinical presentation, diagnosis, and management strategies for a few select, rare congenital malformations of this system. The diagnostic tools used in workup of these disorders range from prenatal tests to radiological imaging, swallowing evaluations, indirect or direct laryngoscopy, and rigid bronchoscopy. While these congenital defects can occur in isolation, they are often associated with disorders of other organ systems or may present as part of a syndrome. Therefore workup and treatment planning for patients with these disorders often involves a team of multiple specialists, including paediatricians, otolaryngologists, pulmonologists, speech pathologists, gastroenterologists, and geneticists. PMID:26277452

  18. Progress in methods for rare variant association.

    PubMed

    Santorico, Stephanie A; Hendricks, Audrey E

    2016-01-01

    Empirical studies and evolutionary theory support a role for rare variants in the etiology of complex traits. Given this motivation and increasing affordability of whole-exome and whole-genome sequencing, methods for rare variant association have been an active area of research for the past decade. Here, we provide a survey of the current literature and developments from the Genetics Analysis Workshop 19 (GAW19) Collapsing Rare Variants working group. In particular, we present the generalized linear regression framework and associated score statistic for the 2 major types of methods: burden and variance components methods. We further show that by simply modifying weights within these frameworks we arrive at many of the popular existing methods, for example, the cohort allelic sums test and sequence kernel association test. Meta-analysis techniques are also described. Next, we describe the 6 contributions from the GAW19 Collapsing Rare Variants working group. These included development of new methods, such as a retrospective likelihood for family data, a method using genomic structure to compare cases and controls, a haplotype-based meta-analysis, and a permutation-based method for combining different statistical tests. In addition, one contribution compared a mega-analysis of family-based and population-based data to meta-analysis. Finally, the power of existing family-based methods for binary traits was compared. We conclude with suggestions for open research questions. PMID:26866487

  19. The structure and stability of aqueous rare-earth elements in hydrothermal fluids: New results on neodymium(III) aqua and chloroaqua complexes in aqueous solutions to 500 °C and 520 MPa

    SciTech Connect

    Mayanovic, R.A.; Anderson, A.J.; Bassett, W.A.; Chou, I.-M.

    2009-02-04

    X-ray absorption spectroscopy (XAS) measurements were made at the Nd L{sub 3}-edge on neodymium(III) aqua and chloroaqua complexes in low pH aqueous solutions from 25 to 500 C and up to 520 MPa. Analysis of the extended X-ray absorption fine structure of the XAS spectra measured from a 0.07 m Nd/0.16 m HNO{sub 3} aqueous solution reveals a contraction of the Nd-O distance of the Nd{sup 3+} aqua ion at a uniform rate of {approx} 0.013 {angstrom}/100 C and a uniform reduction of the number of coordinated H{sub 2}O molecules from 10.0 {+-} 0.9 to 7.4 {+-} 0.9 over the range from 25 to 500 C and up to 370 MPa. The rate of reduction of the first-shell water molecules with temperature for Nd{sup 3+} (26%) is intermediate between the rate for the Gd{sup 3+} aqua ion (22% from 25 to 500 C) and the rates for the Eu{sup 3+} (29% from 25 to 400 C) and the Yb{sup 3+} aqua ions (42% from 25 to 500 C) indicating an intermediate stability of the Nd{sup 3+} aqua ion consistent with the tetrad effect. Nd L{sub 3}-edge XAS measurements of 0.05 m NdCl{sub 3} aqueous solution at 25 to 500 C and up to 520 MPa show that stepwise inner-sphere complexes most likely of the type Nd(H{sub 2}O){sub {delta}-n}Cl{sub n}{sup +3-n} occur in the solution at elevated temperatures, where {delta} {approx} 9 at 150 C decreasing to {approx} 6 at 500 C and the number of chloride ions (n) of the chloroaqua complexes increases uniformly with temperature from 1.2 {+-} 0.2 to 2.0 {+-} 0.2 in the solution upon increase of temperature from 150 to 500 C. Conversely, the number of H{sub 2}O ligands of Nd(H{sub 2}O){sub {delta}-n}Cl{sub n}{sup +3-n} complexes is uniformly reduced with temperature from 7.5 {+-} 0.8 to 3.7 {+-} 0.3 in the aqueous solution, in the same temperature range. These data show greater stability of neodymium(III) than gadolinium(III) and ytterbium(III) chloride complexes in low pH aqueous solutions at elevated temperatures. Our data suggest a greater stability of aqueous light REE than

  20. Fe(II)(pap-5NO2)2 and Fe(II)(qsal-5NO2)2 Schiff-base spin-crossover complexes: a rare example with photomagnetism and room-temperature bistability.

    PubMed

    Iasco, Olga; Rivière, Eric; Guillot, Régis; Buron-Le Cointe, Marylise; Meunier, Jean-François; Bousseksou, Azzedine; Boillot, Marie-Laure

    2015-02-16

    We focus here on the properties of Fe complexes formed with Schiff bases involved in the chemistry of Fe(III) spin-transition archetypes. The neutral Fe(pap-5NO2)2 (1) and Fe(qsal-5NO2)2·Solv (2 and 2·Solv) compounds (Solv = 2H2O) derive from the reaction of Fe(II) salts with the condensation products of pyridine-2-carbaldehyde with 2-hydroxy-5-nitroaniline (Hpap-5NO2) or 5-nitrosalicylaldehyde with quinolin-8-amine (Hqsal-5NO2), respectively. While the Fe(qsal-5NO2)2·Solv solid is essentially low spin (S = 0) and requires temperatures above 300 K to undergo a S = 0 ↔ S = 2 spin-state switching, the Fe(pap-5NO2)2 one presents a strongly cooperative first-order transition (T↓ = 291 K, T↑ = 308 K) centered at room temperature associated with a photomagnetic effect at 10 K (TLIESST = 58 K). The investigation of these magnetic behaviors was conducted with single-crystal X-ray diffraction (1, 100 and 320 K; 2, 100 K), Mössbauer, IR, UV-vis (1 and 2·Solv), and differential scanning calorimetry (1) measurements. The Mössbauer analysis supports a description of these compounds as Fe(II) Schiff-base complexes and the occurrence of a metal-centered spin crossover process. In comparison with Fe(III) analogues, it appears that an expanded coordination sphere stabilizes the valence 2+ state of the Fe ion in both complexes. Strong hydrogen-bonding interactions that implicate the phenolato group bound to Fe(II) promote the required extra-stabilization of the S = 2 state and thus determines the spin transition of 1 centered at room temperature. In the lattice, the hydrogen-bonded sites form infinite chains interconnected via a three-dimensional network of intermolecular van der Waals contacts and π-π interactions. Therefore, the spin transition of 1 involves the synergetic influence of electrostatic and elastic interactions, which cause the enhancement of cooperativity and result in the bistability at room temperature. PMID:25590643

  1. Carney complex.

    PubMed

    Espiard, Stéphanie; Bertherat, Jérôme

    2013-01-01

    Carney complex is a rare, dominantly inherited multiple endocrine neoplasia syndrome, affecting endocrine glands as the adrenal cortex (causing Cushing's syndrome), the pituitary and the thyroid. It is associated with many other nonendocrine tumors, including cardiac myxomas, testicular tumors, melanotic schwannoma, breast myxomatosis, and abnormal pigmentation (lentiginosis) or myxomas of the skin. The gene located on the CNC1 locus was identified 12 years ago as the regulatory subunit 1A (R1A) of the protein kinase A (PRKAR1A) located at 17q22-24. Inactivating heterozygous germline mutations of PRKAR1A are observed in about two thirds of Carney complex patients with some genotype-phenotype correlation useful for follow-up and prognosis. More rarely, mutations of phosphodiesterase genes have been reported in patients presenting mainly with Cushing's syndrome. In vitro and in vivo studies help to understand how R1A inactivation leads to tumorigenesis. PRKAR1A appears to be a relatively weak tumorigenic signal which can cooperate with other signaling pathways and tumor suppressors. PMID:23652670

  2. How to model rare events?

    NASA Astrophysics Data System (ADS)

    Grieser, J.; Jewson, S.

    2009-04-01

    The risk of extreme meteorological events is often estimated using extreme value theory (EVT). However, EVT can't be expected to work well in all cases. Two examples are (a) very rare events which are not adequately captured in short observational records and (b) nonstationary situations where observations alone cannot provide risk estimates for the future. For these reasons Risk Management Solutions (RMS) develops models of extreme weather risks that are based on a combination of both, physics and statistics, rather than just statistics. One example is the RMS TC-Rain model. In addition to wind and storm surge, tropical cyclones (TCs) can lead to torrential rain that may cause widespread flooding and landslides. The most prominent recent historical example is tropical storm Alison (2001) which inundated Houston and caused roughly US 5bn of damage. Since Alison was only tropical storm, rather than a hurricane, no damage due to wind and storm surge was expected and no serious warnings were issued. RMS now has developed a TC-Rain Model which is based on a combination of observations, experience and physical parameterizations. It is an example on how the use of physical principles helps to estimate the risk of rare and devastating events. Based on an event set of TC tracks it allows the calculation of several hundred thousand TC rain footprints which can then be used for the estimation of flood levels and their return periods via a complex dynamical hydrological model. The TC-Rain Model takes a number of physical mechanisms into account, including (a) the effect of surface roughness change at land fall, (b) orographic rain enhancement, (c) drift of rain due to strong horizontal winds, (d) asymmetry, (e) outer rain bands and (f) the dependence on sea surface temperature. It is calibrated using 35 US-landfalling tropical cyclones from 1998 to the 2008, and verified against all US-landfalling TCs since 1948. The model is not designed as a forecasting tool, but rather a

  3. Hybrid materials of SBA-16 functionalized by rare earth (Eu{sup 3+}, Tb{sup 3+}) complexes of modified beta-diketone (TTA and DBM): Covalently bonding assembly and photophysical properties

    SciTech Connect

    Li Yajuan; Yan Bing; Li Ying

    2010-04-15

    Novel mesoporous SBA-16 type of hybrids TTA-S16 and DBM-S16 were synthesized by co-condensation of modified beta-diketone (TTA-Si and DBM-Si, DBM=1,3-diphenyl-1,3- propanepione, TTA=2-thenoyltrifluoroacetone) and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as template, which were confirmed by FTIR, XRD, {sup 29}Si CP-MAS NMR, and N{sub 2} adsorption measurements. Novel organic-inorganic mesoporous luminescent hybrid containing RE{sup 3+} (Eu{sup 3+}, Tb{sup 3+}) complexes covalently attached to the functionalized ordered mesoporous SBA-16 (TTA-S16 and DBM-S16), which were designated as bpy-RE-TTA-S16 and bpy-RE-DBM-S16, were obtained by sol-gel process. The luminescence properties of these resulting materials were characterized in detail, and the results reveal that mesoporous hybrid material bpy-Eu-TTA-S16 present stronger luminescent intensities, longer lifetimes, and higher luminescent quantum efficiencies than the corresponding DBM-containing materials bpy-Eu-DBM-S16, while bpy-Tb-DBM-S16 exhibit the stronger characteristic emission of Tb{sup 3+} and longer lifetime than the corresponding TTA-containing materials bpy-Tb-TTA-S16. - Graphical abstract: Novel organic-inorganic mesoporous luminescent hybrids containing RE{sup 3+} complex covalently attached to the beta-diketone-functionalized ordered mesoporous SBA-16, which were designated as bpy-RE-TTA-S16 and bpy-RE-DBM-S16, were obtained by sol-gel process.

  4. China's rare-earth industry

    USGS Publications Warehouse

    Tse, Pui-Kwan

    2011-01-01

    Introduction China's dominant position as the producer of over 95 percent of the world output of rare-earth minerals and rapid increases in the consumption of rare earths owing to the emergence of new clean-energy and defense-related technologies, combined with China's decisions to restrict exports of rare earths, have resulted in heightened concerns about the future availability of rare earths. As a result, industrial countries such as Japan, the United States, and countries of the European Union face tighter supplies and higher prices for rare earths. This paper briefly reviews China's rare-earth production, consumption, and reserves and the important policies and regulations regarding the production and trade of rare earths, including recently announced export quotas. The 15 lanthanide elements-lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium (atomic numbers 57-71)-were originally known as the rare earths from their occurrence in oxides mixtures. Recently, some researchers have included two other elements-scandium and yttrium-in their discussion of rare earths. Yttrium (atomic number 39), which lies above lanthanum in transition group III of the periodic table and has a similar 3+ ion with a noble gas core, has both atomic and ionic radii similar in size to those of terbium and dysprosium and is generally found in nature with lanthanides. Scandium (atomic number 21) has a smaller ionic radius than yttrium and the lanthanides, and its chemical behavior is intermediate between that of aluminum and the lanthanides. It is found in nature with the lanthanides and yttrium. Rare earths are used widely in high-technology and clean-energy products because they impart special properties of magnetism, luminescence, and strength. Rare earths are also used in weapon systems to obtain the same properties.

  5. Phase stable rare earth garnets

    SciTech Connect

    Kuntz, Joshua D.; Cherepy, Nerine J.; Roberts, Jeffery J.; Payne, Stephen A.

    2013-06-11

    A transparent ceramic according to one embodiment includes a rare earth garnet comprising A.sub.hB.sub.iC.sub.jO.sub.12, where h is 3.+-.10%, i is 2.+-.10%, and j is 3.+-.10%. A includes a rare earth element or a mixture of rare earth elements, B includes at least one of aluminum, gallium and scandium, and C includes at least one of aluminum, gallium and scandium, where A is at a dodecahedral site of the garnet, B is at an octahedral site of the garnet, and C is at a tetrahedral site of the garnet. In one embodiment, the rare earth garment has scintillation properties. A radiation detector in one embodiment includes a transparent ceramic as described above and a photo detector optically coupled to the rare earth garnet.

  6. Rare Down Quark Decays

    NASA Astrophysics Data System (ADS)

    Tung, Kwong-Kwai Humphrey

    1992-01-01

    The rare decays bto sX are sensitive to strong interaction corrections. The effects can be estimated by a renormalization group technique which requires the evaluation of QCD mixing among effective operators. In the dimensional reduction and the naive dimensional regularization methods, there are discrepancies in evaluating the QCD mixing of the four-quark operators with the bto sgamma and bto s+gluon dipole operators. In this thesis, the problem is investigated by considering the contributions of the epsilon -scalar field and the epsilon -dimensional operators that distinguish between the two methods. The discrepancies are shown to come from the epsilon-dimensional four-quark operators in dimensional reduction and not from the epsilon -scalar field. In the decay bto sl^+l^ -, the intermediate of cc pairs in the charm-penguin diagram can form the resonance states J/psi and psi^'. In the published literature, there is a sign discrepancy in the Breit-Wigner amplitude for the resonance effects. Here, the sign difference is settled by considering the unitarity limit of the amplitude in the Argand diagram. The effects of the resonances are quite substantial on the invariant mass spectrum for this decay. However, they are shown to be negligible on the dilepton energy spectrum below 0.95 GeV. The energy spectrum is, thus, more useful than the invariant mass spectrum for measurements of the top -quark mass. The decays Bto K^*X are well modeled by the quark-level decays bto sX. In the quark model, the hadronization is done using a nonrelativistic wave function. In the decay B to K^*gamma, the large K ^* recoil creates an uncertainty in calculating the branching ratio using the quark model. The problem is explored by considering other meson processes where data exist. The data on the pi form factor and the omegapi^0 transition form factor suggest the necessity to retain relativistic spinor and meson normalizations in the quark -model; however, the data do not resolve the

  7. Characteristics and Patterns of Rare Malignancies Published in Rare Tumors

    PubMed Central

    Habboush, Jacob; Hollant, Laeticia; Smart, Brigit; Single, Megan; Gaines, Katherine; Patel, Ajaykumar; Miller, Robert

    2016-01-01

    Rare Tumors is an international peer-reviewed medical journal established in 2009. The journal is focused on rare cancers and aims to expand upon current knowledge on their presentation, diagnosis, management, and outcomes. We reviewed the 335 case reports published from 2009 to 2015. We found great diversity in both the country of origin as well as specialty of first authors. Outside of the United States (US) and European Union (EU), there were 20 countries with contributions to the journal. Similarly, there was representation from twelve medical specialties with first authorship of reports. Rare Tumors continues to encourage involvement from physicians across the globe and from all medical disciplines. PMID:27441071

  8. Characteristics and Patterns of Rare Malignancies Published in Rare Tumors.

    PubMed

    Habboush, Jacob; Hollant, Laeticia; Smart, Brigit; Single, Megan; Gaines, Katherine; Patel, Ajaykumar; Miller, Robert

    2016-06-28

    Rare Tumors is an international peer-reviewed medical journal established in 2009. The journal is focused on rare cancers and aims to expand upon current knowledge on their presentation, diagnosis, management, and outcomes. We reviewed the 335 case reports published from 2009 to 2015. We found great diversity in both the country of origin as well as specialty of first authors. Outside of the United States (US) and European Union (EU), there were 20 countries with contributions to the journal. Similarly, there was representation from twelve medical specialties with first authorship of reports. Rare Tumors continues to encourage involvement from physicians across the globe and from all medical disciplines. PMID:27441071

  9. Rare-earth-metal dialkynyl dimethyl aluminates.

    PubMed

    Nieland, Anja; Mix, Andreas; Neumann, Beate; Stammler, Hans-Georg; Mitzel, Norbert W

    2013-06-17

    A new class of rare-earth-metal alkynyl complexes has been prepared. The reactions of the tris(tetramethylaluminate)s of lanthanum, praseodymium, samarium, yttrium, holmium, and thulium, [Ln(AlMe₄)₃], with phenylacetylene afforded compounds [Ln{(μ-C≡CPh)₂AlMe₂}₃] (Ln=La (1), Pr (2), Sm (3), Y (4), Ho (5), Tm (6)). All of these compounds have been characterized by NMR spectroscopy, X-ray crystallography, and by elemental analysis. NMR spectroscopic studies of the series of para- magnetic compounds [Ln(AlMe₄)₃] and [Ln{(μ-C≡CPh)₂AlMe₂}₃] have also been performed. PMID:23616205

  10. Robust and powerful affected sibpairtest for rare variant association

    PubMed Central

    Lin, Keng-Han; Zöllner, Sebastian

    2015-01-01

    Advances in DNA sequencing technology facilitate investigating the impact of rare variants on complex diseases. However, using a conventional case-control design, large samples are needed to capture enough rare variants to achieve sufficient power for testing the association between suspected loci and complex diseases. In such large samples, population stratification may easily cause spurious signals. One approach to overcome stratification is to use a family-based design. For rare variants, this strategy is especially appropriate, as power can be increased considerably by analyzing cases with affected relatives. We propose a novel framework for association testing in affected sibpairs by comparing the allele count of rare variants on chromosome regions shared identical by descent to the allele count of rare variants on non-shared chromosome regions, referred to as test for rare-variant association with family-based internal control (TRAFIC). This design is generally robust to population stratification as cases and controls are matched within each sibpair. We evaluate the power analytically using general model for effect size of rare variants. For the same number of genotyped people, TRAFIC shows superior power over the conventional case-control study for variants with summed risk allele frequency f < 0.05; this power advantage is even more substantial when considering allelic heterogeneity. For complex models of gene-gene interaction, this power advantage depends on the direction of interaction and overall heritability. In sum, we introduce a new method for analyzing rare variants in affected sibpairs that is robust to population stratification, and provide freely available software. PMID:25966809

  11. Rare times rare: The hyponatremia, rhabdomyolysis, anterior compartment syndrome sequence

    PubMed Central

    Dubin, Ina; Gelber, Moshe

    2016-01-01

    Lesson Primary polydipsia occurs in up to 25% of patients with chronic psychiatric disorders (especially schizophrenia), related to the disease, its treatment or both. Urine output fails to match intake >10 L/day and water intoxication may develop. Rhabdomyolysis is a rare complication of hyponatremia, and an acute anterior compartment syndrome of the leg, an emergency, may be very rarely associated. PMID:27186379

  12. Efficient Estimation of Rare-Event Kinetics

    NASA Astrophysics Data System (ADS)

    Trendelkamp-Schroer, Benjamin; Noé, Frank

    2016-01-01

    The efficient calculation of rare-event kinetics in complex dynamical systems, such as the rate and pathways of ligand dissociation from a protein, is a generally unsolved problem. Markov state models can systematically integrate ensembles of short simulations and thus effectively parallelize the computational effort, but the rare events of interest still need to be spontaneously sampled in the data. Enhanced sampling approaches, such as parallel tempering or umbrella sampling, can accelerate the computation of equilibrium expectations massively, but sacrifice the ability to compute dynamical expectations. In this work we establish a principle to combine knowledge of the equilibrium distribution with kinetics from fast "downhill" relaxation trajectories using reversible Markov models. This approach is general, as it does not invoke any specific dynamical model and can provide accurate estimates of the rare-event kinetics. Large gains in sampling efficiency can be achieved whenever one direction of the process occurs more rapidly than its reverse, making the approach especially attractive for downhill processes such as folding and binding in biomolecules. Our method is implemented in the PyEMMA software.

  13. Rare Presentation of Ophthalmia Nodosa.

    PubMed

    Prasad, Shimna Clara; Korah, Sanita

    2015-01-01

    We report a rare case of ophthalmia nodosa, presenting as a painless swelling in the lower palpebral conjunctiva for 2 years with no signs of inflammation. Excision biopsy confirmed the diagnosis. PMID:26692729

  14. Rare Presentation of Ophthalmia Nodosa

    PubMed Central

    Prasad, Shimna Clara; Korah, Sanita

    2015-01-01

    We report a rare case of ophthalmia nodosa, presenting as a painless swelling in the lower palpebral conjunctiva for 2 years with no signs of inflammation. Excision biopsy confirmed the diagnosis. PMID:26692729

  15. The Not-So-Rare Earths.

    ERIC Educational Resources Information Center

    Muecke, Gunter K.; Moller, Peter

    1988-01-01

    Describes the characteristics of rare earth elements. Details the physical chemistry of rare earths. Reviews the history of rare earth chemistry and mineralogy. Discusses the mineralogy and crystallography of the formation of rare earth laden minerals found in the earth's crust. Characterizes the geologic history of rare earth elements. (CW)

  16. Rare Earth Optical Temperature Sensor

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (Inventor); Jenkins, Phillip (Inventor)

    2004-01-01

    A rare earth optical temperature sensor is disclosed for measuring high temperatures. Optical temperature sensors exist that channel emissions from a sensor to a detector using a light pipe. The invention uses a rare earth emitter to transform the sensed thermal energy into a narrow band width optical signal that travels to a detector using a light pipe. An optical bandpass filter at the detector removes any noise signal outside of the band width of the signal from the emitter.

  17. Craniopagus parasiticus: A rare case.

    PubMed

    Kansal, Ritesh; Kale, Chirag; Goel, Atul

    2010-10-01

    Conjoined twins or Siamese twins are identical twins whose bodies are joined in the uterus. Craniopagus is a condition in which the heads of the two twins are joined. Craniopagus parasiticus is a rare condition in which one of the twins is rudimentary in form and parasitic on the other. Few cases of craniopagus parasiticus are reported in literature; here, we present one such rare occurrence. PMID:20655232

  18. [Adult-onset rare diseases].

    PubMed

    Pfliegler, György; Kovács, Erzsébet; Kovács, György; Urbán, Krisztián; Nagy, Valéria; Brúgós, Boglárka

    2014-03-01

    The present paper is focusing on rare diseases manifesting in late childhood or adulthood. A part of these syndromes are not of genetic origin, such as relatively or absolutely rare infections, autoimmune diseases, tumours, or diseases due to rare environmental toxic agents. In addition, even a large proportion of genetic disorders may develop in adulthood or may have adult forms as well, affecting are almost each medical specialization. Examples are storage disorders (e.g. adult form of Tay-Sachs disease, Gaucher-disease), enzyme deficiencies (e.g. ornithin-transcarbamylase deficiency of the urea cycle disorders), rare thrombophilias (e.g. homozygous factor V. Leiden mutation, antithrombin deficiency), or some rare monogenic disorders such as Huntington-chorea and many others. It is now generally accepted that at least half of the 6-8000 "rare diseases" belong either to the scope of adult-care (e.g. internal medicine, neurology), or to "age-neutral" specialities such as ophtalmology, dermatology etc.). PMID:24566697

  19. Signs and genetics of rare cancer syndromes with gastroenterological features.

    PubMed

    Bruno, William; Fornarini, Giuseppe; Ghiorzo, Paola

    2015-08-14

    Although the genetic bases of most hereditary cancer syndromes are known, and genetic tests are available for them, the incidence of the most rare of these syndromes is likely underestimated, partially because the clinical expression is neither fully understood nor easily diagnosed due to the variable and complex expressivity. The clinical features of a small pool of rare cancer syndromes include gastroenterological signs, though not necessarily tumors, that could require the intervention of a gastroenterologist during any of the phases of the clinical management. Herein we will attempt to spread the knowledge on these rare syndromes by summarizing the phenotype and genetic basis, and revising the peculiar gastroenterological signs whose underlying role in these rare hereditary cancer syndromes is often neglected. Close collaboration between geneticists and gastroenterologists could facilitate both the early identification of patients or relatives at-risk and the planning of multidisciplinary and tailored management of these subjects. PMID:26290627

  20. Present status of Rare-RI Ring facility at RIBF

    NASA Astrophysics Data System (ADS)

    T Yamaguchithe Rare-RI Ring Collaboration

    2015-11-01

    A new storage ring facility called the Rare-RI Ring is currently under preparation at the RI Beam Factory (RIBF) in RIKEN. The storage ring is dedicated to the single-ion precision mass spectrometry of neutron-rich exotic nuclei. The masses are essential to elucidate the evolution of the nuclear shell structure far from the β stability and to determine the pathway of astrophysical nucleosynthesis. Such exotic nuclei are provided by the large-acceptance superconducting fragment separator, BigRIPS, at the RIBF accelerator complex. The experimental principle of the Rare-RI Ring mass measurements is based on isochronous mass spectrometry combined with the individual injection technique. This novel technique enables exotic species of interest to be produced randomly, in time to be sequentially stored in the storage ring. The Rare-RI Ring facility realizes the most efficient measurements for rare isotopes. An overview of the project is presented, along with its present status.

  1. Signs and genetics of rare cancer syndromes with gastroenterological features

    PubMed Central

    Bruno, William; Fornarini, Giuseppe; Ghiorzo, Paola

    2015-01-01

    Although the genetic bases of most hereditary cancer syndromes are known, and genetic tests are available for them, the incidence of the most rare of these syndromes is likely underestimated, partially because the clinical expression is neither fully understood nor easily diagnosed due to the variable and complex expressivity. The clinical features of a small pool of rare cancer syndromes include gastroenterological signs, though not necessarily tumors, that could require the intervention of a gastroenterologist during any of the phases of the clinical management. Herein we will attempt to spread the knowledge on these rare syndromes by summarizing the phenotype and genetic basis, and revising the peculiar gastroenterological signs whose underlying role in these rare hereditary cancer syndromes is often neglected. Close collaboration between geneticists and gastroenterologists could facilitate both the early identification of patients or relatives at-risk and the planning of multidisciplinary and tailored management of these subjects. PMID:26290627

  2. Bayesian analysis of rare events

    NASA Astrophysics Data System (ADS)

    Straub, Daniel; Papaioannou, Iason; Betz, Wolfgang

    2016-06-01

    In many areas of engineering and science there is an interest in predicting the probability of rare events, in particular in applications related to safety and security. Increasingly, such predictions are made through computer models of physical systems in an uncertainty quantification framework. Additionally, with advances in IT, monitoring and sensor technology, an increasing amount of data on the performance of the systems is collected. This data can be used to reduce uncertainty, improve the probability estimates and consequently enhance the management of rare events and associated risks. Bayesian analysis is the ideal method to include the data into the probabilistic model. It ensures a consistent probabilistic treatment of uncertainty, which is central in the prediction of rare events, where extrapolation from the domain of observation is common. We present a framework for performing Bayesian updating of rare event probabilities, termed BUS. It is based on a reinterpretation of the classical rejection-sampling approach to Bayesian analysis, which enables the use of established methods for estimating probabilities of rare events. By drawing upon these methods, the framework makes use of their computational efficiency. These methods include the First-Order Reliability Method (FORM), tailored importance sampling (IS) methods and Subset Simulation (SuS). In this contribution, we briefly review these methods in the context of the BUS framework and investigate their applicability to Bayesian analysis of rare events in different settings. We find that, for some applications, FORM can be highly efficient and is surprisingly accurate, enabling Bayesian analysis of rare events with just a few model evaluations. In a general setting, BUS implemented through IS and SuS is more robust and flexible.

  3. A Rare Cause of Prepubertal Gynecomastia: Sertoli Cell Tumor

    PubMed Central

    Dursun, Fatma; Su Dur, Şeyma Meliha; Şahin, Ceyhan; Kırmızıbekmez, Heves; Karabulut, Murat Hakan; Yörük, Asım

    2015-01-01

    Prepubertal gynecomastia due to testis tumors is a very rare condition. Nearly 5% of the patients with testicular mass present with gynecomastia. Sertoli cell tumors are sporadic in 60% of the reported cases, while the remaining is a component of multiple neoplasia syndromes such as Peutz-Jeghers syndrome and Carney complex. We present a 4-year-old boy with gynecomastia due to Sertoli cell tumor with no evidence of Peutz-Jeghers syndrome or Carney complex. PMID:26366315

  4. Bobble head doll syndrome: A rare case report

    PubMed Central

    Reddy, Onteddoo Joji; Gafoor, Jamkhana Abdul; Suresh, Balla; Prasad, P. Obuleswar

    2014-01-01

    Bobble – head syndrome (BHDS) is a complex and rare syndrome with repetitive anteroposterior head movements. It is usually associated with expansile lesions in the third ventricular region. We present a 9 year old child with a giant suprasellar arachnoid cyst causing involuntary head movements. PMID:25250081

  5. Bobble head doll syndrome: A rare case report.

    PubMed

    Reddy, Onteddoo Joji; Gafoor, Jamkhana Abdul; Suresh, Balla; Prasad, P Obuleswar

    2014-05-01

    Bobble - head syndrome (BHDS) is a complex and rare syndrome with repetitive anteroposterior head movements. It is usually associated with expansile lesions in the third ventricular region. We present a 9 year old child with a giant suprasellar arachnoid cyst causing involuntary head movements. PMID:25250081

  6. Microbial community assembly, theory and rare functions.

    PubMed

    Pholchan, Mujalin K; Baptista, Joana de C; Davenport, Russell J; Sloan, William T; Curtis, Thomas P

    2013-01-01

    Views of community assembly have traditionally been based on the contrasting perspectives of the deterministic niche paradigm and stochastic neutral models. This study sought to determine if we could use empirical interventions conceived from a niche and neutral perspective to change the diversity and evenness of the microbial community within a reactor treating wastewater and to see if there was any associated change in the removal of endocrine disrupting compounds (EDCs). The systematic removal of EDCs and micropollutants from biological treatment systems is a major challenge for environmental engineers. We manipulated pairs of bioreactors in an experiment in which "niche" (temporal variation in resource concentration and resource complexity) and "neutral" (community size and immigration) attributes were changed and the effect on the detectable diversity and the removal of steroidal estrogens was evaluated. The effects of manipulations on diversity suggested that both niche and neutral processes are important in community assembly. We found that temporal variation in environmental conditions increased diversity but resource complexity did not. Larger communities had greater diversity but attempting to increase immigration by adding soil had the opposite effect. The effects of the manipulations on EDC removal efficiency were complex. Decreases in diversity, which were associated with a decrease in evenness, were associated with an increase in EDC removal. A simple generalized neutral model (calibrated with parameters typical of wastewater treatment plants) showed that decreases in diversity should lead to the increase in abundance of some ostensibly taxa rare. We conclude that neither niche and neutral perspectives nor the effect of diversity on putative rare functions can be properly understood by naïve qualitative observations. Instead, the relative importance of the key microbial mechanisms must be determined and, ideally, expressed mathematically. PMID

  7. Microbial community assembly, theory and rare functions

    PubMed Central

    Pholchan, Mujalin K.; Baptista, Joana de C.; Davenport, Russell J.; Sloan, William T.; Curtis, Thomas P.

    2013-01-01

    Views of community assembly have traditionally been based on the contrasting perspectives of the deterministic niche paradigm and stochastic neutral models. This study sought to determine if we could use empirical interventions conceived from a niche and neutral perspective to change the diversity and evenness of the microbial community within a reactor treating wastewater and to see if there was any associated change in the removal of endocrine disrupting compounds (EDCs). The systematic removal of EDCs and micropollutants from biological treatment systems is a major challenge for environmental engineers. We manipulated pairs of bioreactors in an experiment in which “niche” (temporal variation in resource concentration and resource complexity) and “neutral” (community size and immigration) attributes were changed and the effect on the detectable diversity and the removal of steroidal estrogens was evaluated. The effects of manipulations on diversity suggested that both niche and neutral processes are important in community assembly. We found that temporal variation in environmental conditions increased diversity but resource complexity did not. Larger communities had greater diversity but attempting to increase immigration by adding soil had the opposite effect. The effects of the manipulations on EDC removal efficiency were complex. Decreases in diversity, which were associated with a decrease in evenness, were associated with an increase in EDC removal. A simple generalized neutral model (calibrated with parameters typical of wastewater treatment plants) showed that decreases in diversity should lead to the increase in abundance of some ostensibly taxa rare. We conclude that neither niche and neutral perspectives nor the effect of diversity on putative rare functions can be properly understood by naïve qualitative observations. Instead, the relative importance of the key microbial mechanisms must be determined and, ideally, expressed mathematically

  8. [Complex odontoma with dentigerous cyst: a case report].

    PubMed

    Qizhang, Xu; Hongliang, Zhang; Xiaoyu, Wang; Zhanji, Wang; Qianqian, Xu; Qiong, Ma

    2014-12-01

    Complex odontoma is a relatively rare dental dysplasia. In particular, a complex odontoma with dentigerous cyst is seldom observed. A case of complex odontoma with dentigerous cyst is reported in this paper. PMID:25665433

  9. Ainhum - A Rare Case Report

    PubMed Central

    Prabhu, Ravi; Vinoth, Sundaresan; Praveen, Chinnappan Balasubramanian

    2016-01-01

    The term ‘AINHUM’ is derived from the African word meaning ‘to saw or cut’. True ainhum otherwise called dactylolysis spontanea is a condition involving soft tissue or digits with constricting rings commonly presenting in fifth toes, usually bilateral. It is to be differentiated from Pseudo-ainhum that occurs secondary to some hereditary and nonhereditary diseases that lead to annular constriction of digits. We report a rare case of true ainhum involving the left fourth toe only. It is a very rare case and a very few were reported worldwide. The highest incidence of ainhum has been reported in South Africa and South America. It is rarely reported in India. Ainhum when diagnosed and treated in early stages can be prevented from progressing to mutilating deformities. PMID:27190888

  10. Ainhum - A Rare Case Report.

    PubMed

    Prabhu, Ravi; Kannan, Narayanasamy Subbaraju; Vinoth, Sundaresan; Praveen, Chinnappan Balasubramanian

    2016-04-01

    The term 'AINHUM' is derived from the African word meaning 'to saw or cut'. True ainhum otherwise called dactylolysis spontanea is a condition involving soft tissue or digits with constricting rings commonly presenting in fifth toes, usually bilateral. It is to be differentiated from Pseudo-ainhum that occurs secondary to some hereditary and nonhereditary diseases that lead to annular constriction of digits. We report a rare case of true ainhum involving the left fourth toe only. It is a very rare case and a very few were reported worldwide. The highest incidence of ainhum has been reported in South Africa and South America. It is rarely reported in India. Ainhum when diagnosed and treated in early stages can be prevented from progressing to mutilating deformities. PMID:27190888

  11. Building treasures for rare disorders.

    PubMed

    Baas, Melanie; Huisman, Sylvia; van Heukelingen, John; Koekkoek, Gerritjan; Laan, Henk-Willem; Hennekam, Raoul C

    2015-01-01

    The internet pre-eminently marks an era with unprecedented chances for patient care. Especially individuals with rare disorders and their families can benefit. Their handicap of low numbers vanishes and can become a strength, as small, motivated and well-organized international support groups allow easily fruitful collaborations with physicians and researchers. Jointly setting research agendas and building wikipedias has eventually led to building of multi-lingual databases of longitudinal data on physical and behavioural characteristics of individuals with several rare disorders which we call waihonapedias (waihona meaning treasure in Hawaiian). There are hurdles to take, like online security and reliability of diagnoses, but sharing experiences and true collaborations will allow better research and patient care for fewer costs to patients with rare disorders. PMID:25449139

  12. DGTI Register of Rare Donors

    PubMed Central

    Hustinx, Hein

    2014-01-01

    Summary For patients with antibodies against the most common blood groups a rapid and efficient supply of compatible erythrocyte concentrates is self-evident. But typically we have to make the greatest effort providing blood for these patients, which have made antibodies against common blood groups. There are however patients with antibodies against rare blood group antigens that need special blood. The supply of such blood can be very difficult and mostly time-consuming. For this reason we set up a database of blood donors with rare blood groups. Since 2005 the BTS SRC Berne Ltd. has run this database on behalf of the Swiss BTS SRC. After a reorganization and extension of the database, conducted during 2011/2012, the data file was renamed ‘DGTI Register of Rare Donors’ and is now run under the patronage of the German Society for Transfusion Medicine and Immunohematology (DGTI). PMID:25538534

  13. Dioctophymiasis: A Rare Case Report.

    PubMed

    Chauhan, Sapna; Kaval, Sunil; Tewari, Swati

    2016-02-01

    Dioctophyma renale commonly known as "giant kidney worm' is found in the kidney of carnivorous mammals. Human infestation is rare, but results in destruction of the kidneys. Very few cases have been reported worldwide. We are here reporting a case of Dioctophymiasis in a 35-year-old male patient who presented with retention of urine and subsequent passage of worm and blood in urine. The worm was confirmed as Dioctophyma renale based on its morphology and clinical presentation. This is a very rare case report and to best of our knowledge only two cases have been reported from India. PMID:27042466

  14. A rare urinary bladder tumour

    PubMed Central

    Haddad-Lacle, Judella Edwina Maria; Haddad, Charles Joseph; Villas, Bruce

    2014-01-01

    This case report describes a 54-year-old man who presented to his primary care physician with low back pain. During his workup, an incidental finding of a bladder mass was diagnosed. He underwent transurethral resection of the bladder tumour and the resulting pathology was consistent with extra nodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Presentation of MALT lymphoma in the urinary bladder is rare. This malignancy is more commonly found in the stomach. The prognosis for this rare tumour is excellent. Our patient showed no sign of recurrence with transurethral excision and radiation alone. PMID:24835803

  15. Dioctophymiasis: A Rare Case Report

    PubMed Central

    Kaval, Sunil; Tewari, Swati

    2016-01-01

    Dioctophyma renale commonly known as “giant kidney worm’ is found in the kidney of carnivorous mammals. Human infestation is rare, but results in destruction of the kidneys. Very few cases have been reported worldwide. We are here reporting a case of Dioctophymiasis in a 35-year-old male patient who presented with retention of urine and subsequent passage of worm and blood in urine. The worm was confirmed as Dioctophyma renale based on its morphology and clinical presentation. This is a very rare case report and to best of our knowledge only two cases have been reported from India. PMID:27042466

  16. Molecular rare-earth-metal hydrides in non-cyclopentadienyl environments.

    PubMed

    Fegler, Waldemar; Venugopal, Ajay; Kramer, Mathias; Okuda, Jun

    2015-02-01

    Molecular hydrides of the rare-earth metals play an important role as homogeneous catalysts and as counterparts of solid-state interstitial hydrides. Structurally well-characterized non-metallocene-type hydride complexes allow the study of elementary reactions that occur at rare-earth-metal centers and of catalytic reactions involving bonds between rare-earth metals and hydrides. In addition to neutral hydrides, cationic derivatives have now become available. PMID:25413985

  17. Marker-specific sorting of rare cells using dielectrophoresis

    PubMed Central

    Hu, Xiaoyuan; Bessette, Paul H.; Qian, Jiangrong; Meinhart, Carl D.; Daugherty, Patrick S.; Soh, Hyongsok T.

    2005-01-01

    Current techniques in high-speed cell sorting are limited by the inherent coupling among three competing parameters of performance: throughput, purity, and rare cell recovery. Microfluidics provides an alternate strategy to decouple these parameters through the use of arrayed devices that operate in parallel. To efficiently isolate rare cells from complex mixtures, an electrokinetic sorting methodology was developed that exploits dielectrophoresis (DEP) in microfluidic channels. In this approach, the dielectrophoretic amplitude response of rare target cells is modulated by labeling cells with particles that differ in polarization response. Cell mixtures were interrogated in the DEP-activated cell sorter in a continuous-flow manner, wherein the electric fields were engineered to achieve efficient separation between the dielectrophoretically labeled and unlabeled cells. To demonstrate the efficiency of marker-specific cell separation, DEP-activated cell sorting (DACS) was applied for affinity-based enrichment of rare bacteria expressing a specific surface marker from an excess of nontarget bacteria that do not express this marker. Rare target cells were enriched by >200-fold in a single round of sorting at a single-channel throughput of 10,000 cells per second. DACS offers the potential for automated, surface marker-specific cell sorting in a disposable format that is capable of simultaneously achieving high throughput, purity, and rare cell recovery. PMID:16236724

  18. Selective Emitter Pumped Rare Earth Laser

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (Inventor); Patton, Martin O. (Inventor)

    2001-01-01

    A selective emitter pumped rare earth laser provides an additional type of laser for use in many laser applications. Rare earth doped lasers exist which are pumped with flashtubes or laser diodes. The invention uses a rare earth emitter to transform thermal energy input to a spectral band matching the absorption band of a rare earth in the laser in order to produce lasing.

  19. RARE II: The Administration's View

    ERIC Educational Resources Information Center

    Cutler, M. Rupert

    1977-01-01

    RARE II is a new Roadless Area Review and Evaluation of the National Forest system. Administrators are attempting to inventory existing wilderness areas and to determine criteria for setting aside additional ones. This information will be used for the required 1980 update of the national assessment of forests and rangelands. (MA)

  20. Rare B decays at CDF

    SciTech Connect

    Farrington, Sinead M.; /Liverpool U.

    2006-10-01

    The confidence level limits of the CDF search for the B{sub s}{sup 0} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -} rare decays and the branching ratio measurement of B{sub s}{sup 0} {yields} D{sub s}{sup +} D{sub s}{sup -} are presented.

  1. Rare-event recorder interface

    SciTech Connect

    Kuts, V.N.

    1984-03-01

    The author describes an interface for a BPA2-95 analog-digital computer with PL-80 and a Perfomom 30 perferator for rare event recording. This interface allows the height of each pulse that passes through the analog-digital converter to be recorded on punch tape. A series of three block diagrams illustrates in thorough detail the system described.

  2. Cardiofaciocutaneous Syndrome: A Rare Entity

    PubMed Central

    Pavithra, S; Mallya, H; Pai, G S

    2012-01-01

    The cardiofaciocutaneous (CFC) syndrome is a condition of sporadic occurrence, with patients showing multiple congenital anomalies and mental retardation and characteristic dysmorphic features. We, thus, report a rare case of this syndrome in a 1-year-old child who presented with typical features of CFC syndrome. PMID:22837569

  3. Rare events: a state of the art

    SciTech Connect

    Uppuluri, V.R.R.

    1980-12-01

    The study of rare events has become increasingly important in the context of nuclear safety. Some philosophical considerations, such as the framework for the definition of a rare event, rare events and science, rare events and trans-science, and rare events and public perception, are discussed. The technical work of the Task Force on problems of Rare Events in the Reliability Analysis of Nuclear Plants (1976-1978), sponsored by OECD, is reviewed. Some recent technical considerations are discussed, and conclusions are drawn. The appendix contains an essay written by Anne E. Beachey, under the title: A Study of Rare Events - Problems and Promises.

  4. Ultra-rare Disease and Genomics-Driven Precision Medicine

    PubMed Central

    Lee, Sangmoon

    2016-01-01

    Since next-generation sequencing (NGS) technique was adopted into clinical practices, revolutionary advances in diagnosing rare genetic diseases have been achieved through translating genomic medicine into precision or personalized management. Indeed, several successful cases of molecular diagnosis and treatment with personalized or targeted therapies of rare genetic diseases have been reported. Still, there are several obstacles to be overcome for wider application of NGS-based precision medicine, including high sequencing cost, incomplete variant sensitivity and accuracy, practical complexities, and a shortage of available treatment options. PMID:27445646

  5. Adolescent Mandibular Central Odontoameloblastoma: A Rare Case Report.

    PubMed

    Arun Kumar, K V; Mowar, Apoorva; Gupta, Rajat; Deepa, D

    2016-03-01

    Odontoameloblastoma is a rare odontogenic tumour, characterised by simultaneous occurrence of an ameloblastoma and a compound or complex odontoma in the same tumoral mass. The tumour is seen in first three decades and affects mandible or maxilla equally, commonly found posterior to the canines. The management is similar to unicystic ameloblastoma and odontoma excision. A long term follow up is a must to observe the recurrence. Here we present a rare case of odontoameloblastoma in a 17 year old male, presenting as an asymptomatic anterior mandibular swelling with chief complaint of missing lower front teeth. PMID:26929561

  6. A Rare Case of Mucopolysaccharidosis: Hunter Syndrome

    PubMed Central

    Anekar, Jayaprasad; A.C., Raj; N.C., Sandeepa; Nappalli, Deepika

    2015-01-01

    Hunter syndrome, or mucopolysaccharidosis type II (MPS II), is a member of a group of inherited metabolic disorders together termed mucopolysaccharidosis (MPSs). It is a rare, X-linked disorder caused by a deficiency of the lysosomal enzyme iduronate-2-sulfatase. The prevalence of this syndrome is 1:100,000 births. Insufficient enzyme activity results in accumulation of glycosaminoglycans (GAGS) in the lysosomes of various tissues and organs and leading to progressive multisystem pathologies. Here, we report a case of 13-year-old boy who presented with typical facial, skeletal and dental features without corneal clouding. It is possible that thorough and systematic clinical and radiological examination alone can help in diagnosis of this complex disorder. PMID:26023658

  7. Quantifying metastatic inefficiency: rare genotypes versus rare dynamics

    NASA Astrophysics Data System (ADS)

    Cisneros, Luis H.; Newman, Timothy J.

    2014-08-01

    We introduce and solve a ‘null model’ of stochastic metastatic colonization. The model is described by a single parameter θ: the ratio of the rate of cell division to the rate of cell death for a disseminated tumour cell in a given secondary tissue environment. We are primarily interested in the case in which colonizing cells are poorly adapted for proliferation in the local tissue environment, so that cell death is more likely than cell division, i.e. \\theta \\lt 1. We quantify the rare event statistics for the successful establishment of a metastatic colony of size N. For N\\gg 1, we find that the probability of establishment is exponentially rare, as expected, and yet the mean time for such rare events is of the form \\sim log (N)/(1-\\theta ) while the standard deviation of colonization times is \\sim 1/(1-\\theta ). Thus, counter to naive expectation, for \\theta \\lt 1, the average time for establishment of successful metastatic colonies decreases with decreasing cell fitness, and colonies seeded from lower fitness cells show less stochastic variation in their growth. These results indicate that metastatic growth from poorly adapted cells is rare, exponentially explosive and essentially deterministic. These statements are brought into sharper focus by the finding that the temporal statistics of the early stages of metastatic colonization from low-fitness cells (\\theta \\lt 1) are statistically indistinguishable from those initiated from high-fitness cells (\\theta \\gt 1), i.e. the statistics show a duality mapping (1-\\theta )\\to (\\theta -1). We conclude our analysis with a study of heterogeneity in the fitness of colonising cells, and describe a phase diagram delineating parameter regions in which metastatic colonization is dominated either by low or high fitness cells, showing that both are plausible given our current knowledge of physiological conditions in human cancer.

  8. Rare Earth Garnet Selective Emitter

    NASA Technical Reports Server (NTRS)

    Lowe, Roland A.; Chubb, Donald L.; Farmer, Serene C.; Good, Brian S.

    1994-01-01

    Thin film Ho-YAG and Er-YAG emitters with a platinum substrate exhibit high spectral emittance in the emission band (epsilon(sub lambda) approx. = 0.75, sup 4)|(sub 15/2) - (sup 4)|(sub 13/2),for Er-YAG and epsilon(sub lambda) approx. = 0.65, (sup 5)|(sub 7) - (sup 5)|(sub 8) for Ho-YAG) at 1500 K. In addition, low out-of-band spectral emittance, epsilon(sub lambda) less than 0.2, suggest these materials would be excellent candidates for high efficiency selective emitters in thermophotovoltaic (TPV) systems operating at moderate temperatures (1200-1500 K). Spectral emittance measurements of the thin films were made (1.2 less than lambda less than 3.0 microns) and compared to the theoretical emittances calculated using measured values of the spectral extinction coefficient. In this paper we present the results for a new class of rare earth ion selective emitters. These emitters are thin sections (less than 1 mm) of yttrium aluminum garnet (YAG) single crystal with a rare earth substitutional impurity. Selective emitters in the near IR are of special interest for thermophotovoltaic (TPV) energy conversion. The most promising solid selective emitters for use in a TPV system are rare earth oxides. Early spectral emittance work on rare earth oxides showed strong emission bands in the infrared (0.9 - 3 microns). However, the emittance outside the emission band was also significant and the efficiency of these emitters was low. Recent improvements in efficiency have been made with emitters fabricated from fine (5 - 10 microns) rare earth oxide fibers similar to the Welsbach mantle used in gas lanterns. However, the rare earth garnet emitters are more rugged than the mantle type emitters. A thin film selective emitter on a low emissivity substrate such as gold, platinum etc., is rugged and easily adapted to a wide variety of thermal sources. The garnet structure and its many subgroups have been successfully used as hosts for rare earth ions, introduced as substitutional

  9. Rare essentials: drugs for rare diseases as essential medicines.

    PubMed

    Stolk, Pieter; Willemen, Marjolein J C; Leufkens, Hubert G M

    2006-09-01

    Since 1977, the WHO Model List of Essential Medicines (EML), published by WHO, has provided advice for Member States that struggle to decide which pharmaceutical technologies should be provided to patients within their public health systems. Originating from outside WHO, an incentive system has been put in place by various governments for the development of medicines for rare diseases ("orphan drugs"). With progress in pharmaceutical research (e.g. drugs targeted for narrower indications), these medicines will feature more often on future public health agendas. However, when current definitions for selecting essential medicines are applied strictly, orphan drugs cannot be part of the WHO Essential Medicines Programme, creating the risk that WHO may lose touch with this field. In our opinion WHO should explicitly include orphan drugs in its policy sphere by composing a complementary Orphan Medicines Model List as an addition to the EML. This complementary list of "rare essentials" could aid policy-makers and patients in, for example, emerging countries to improve access to these drugs and stimulate relevant policies. Furthermore, inconsistencies in the current EML with regard to medicines for rare diseases can be resolved. In this paper we propose selection criteria for an Orphan Medicines Model List that could form a departure point for future work towards an extensive WHO Orphan Medicines Programme. PMID:17128345

  10. Cloacal Exstrophy with Mature Teratoma: A Rare Association in a Neonate.

    PubMed

    Patil, Prashant Sadashiv; Kothari, Paras; Gupta, Abhaya; Gupta, Rahul; Kekre, Geeta; Dikshit, Vishesh; Kamble, Ravi

    2016-01-01

    Cloacal exstrophy is a very rare and complex malformation. We report a neonate of cloacal exstrophy with mature teratoma presenting as a component of exstrophy. To our knowledge this has not been reported in the literature. PMID:27123401

  11. Cloacal Exstrophy with Mature Teratoma: A Rare Association in a Neonate

    PubMed Central

    Patil, Prashant Sadashiv; Kothari, Paras; Gupta, Abhaya; Gupta, Rahul; kekre, Geeta; Dikshit, Vishesh; Kamble, Ravi

    2016-01-01

    Cloacal exstrophy is a very rare and complex malformation. We report a neonate of cloacal exstrophy with mature teratoma presenting as a component of exstrophy. To our knowledge this has not been reported in the literature. PMID:27123401

  12. Rare Earth Optical Temperature Sensor

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.; Wolford, David S.

    2000-01-01

    A new optical temperature sensor suitable for high temperatures (greater than 1700 K) and harsh environments is introduced. The key component of the sensor is the rare earth material contained at the end of a sensor that is in contact with the sample being measured. The measured narrow wavelength band emission from the rare earth is used to deduce the sample temperature. A simplified relation between the temperature and measured radiation was verified experimentally. The upper temperature limit of the sensor is determined by material limits to be approximately 2000 C. The lower limit, determined by the minimum detectable radiation, is found to be approximately 700 K. At high temperatures 1 K resolution is predicted. Also, millisecond response times are calculated.

  13. The rare benign liver tumors.

    PubMed

    Skalicky, T; Treska, V; Liska, V; Sutnar, A; Molacek, J; Mirka, H; Ferda, J; Ohlidalova, K

    2007-01-01

    As opposed to malignant secondary tumors, metastases of the colorectal carcinoma are benign tumors of the liver that are quite rare in the Czech Republic. From the 55 patients operated on since 2000 at our department for benign liver tumors, the most frequent are haemangiomas, focal nodular hyperplasia (FNH) and hepatocelular adenoma. Only 7.3% of them form a different histological type of a tumor than this most frequently occurring trio of tumors. The authors describe three cases of rather rare liver tumors with benign behavior that have the potential of becoming malignant. It concerns mucin producing biliary tumors, which correspond to the pancreatic intraductal papillary mucin tumor, hepatic cystadenoma with ovarian stroma and a liver hamartoma in an adult patient (Ref 13). Full Text (Free, PDF) www.bmj.sk. PMID:17694811

  14. A rare benign ovarian tumour.

    PubMed

    Palmeiro, Marta Morna; Cunha, Teresa Margarida; Loureiro, Ana Luisa; Esteves, Gonçalo

    2016-01-01

    Sclerosing stromal tumour (SST) of the ovary is an extremely rare and benign ovarian neoplasm, accounting for 6% of the sex cord stromal ovarian tumours subtype. Usually, it is found during the second and third decades of life. Patients commonly present with pelvic pain, a palpable pelvic mass or menstrual irregularity. We report a case of a 20-year-old woman reporting of mild pelvic pain, with normal laboratory data. On imaging examinations, a large right adnexal tumour was found, with features suggesting an ovarian sex cord tumour. The patient underwent right salpingo-oophorectomy, diagnosing a SST of the ovary. This paper also reviews the literature, and emphasises the typical pathological and imaging characteristics of these rare benign ovarian lesions, and their impact, in a conservative surgery. PMID:26933186

  15. Testicular calculus: A rare case

    PubMed Central

    Sen, Volkan; Bozkurt, Ozan; Demir, Omer; Tuna, Burcin; Yorukoglu, Kutsal; Esen, Adil

    2015-01-01

    ABSTRACT Background: Testicular calculus is an extremely rare case with unknown etiology and pathogenesis. To our knowledge, here we report the third case of testicular calculus. A 31-year-old man was admitted to our clinic with painful solid mass in left testis. After diagnostic work-up for a possible testicular tumour, he underwent inguinal orchiectomy and histopathologic examination showed a testicular calculus. Case hypothesis: Solid testicular lesions in young adults generally correspond to testicular cancer. Differential diagnosis should be done carefully. Future implications: In young adults with painful and solid testicular mass with hyperechogenic appearance on scrotal ultrasonography, testicular calculus must be kept in mind in differential diagnosis. Further reports on this topic may let us do more clear recommendations about the etiology and treatment of this rare disease. PMID:26200556

  16. Intracranial chondroma: a rare entity

    PubMed Central

    Maheshwari, Veena; Mehdi, Ghazala; Varshney, Manoranjan; Jain, Anshu; Vashishtha, Sonal; Gaur, Kavita; Srivastava, Vinod Kumar

    2011-01-01

    Intracranial chondroma is a rare benign cartilaginous tumour with an incidence of less than 1% of all primary intracranial tumours. The authors are reporting here a case of intracranial chondroma in a 40-year-old man who presented with 5-month history of headache and gradual diminution of vision. A tentative diagnosis of chondroma was made on imprint cytology which was confirmed on histopathological examination. PMID:22696735

  17. Perilymph Fistula: Rare but Real

    PubMed Central

    Gleeson, Susan E.; Williams, D. Malcolm

    1989-01-01

    Although perilymph fistula is a rare diagnosis, it is important that family physicians be aware of the signs and symptoms that suggest its presence. When a patient develops sudden loss of hearing and/or vestibular dysfunction after experiencing trauma to the head or ears, after barotrauma, or after performing a vigorous Valsalva manoeuvre, he should be referred promptly to an otolaryngologist for assessment and proper management of the condition. ImagesFigure 1 PMID:21249027

  18. Optical Frequency Comb Spectroscopy of Rare Earth Atoms

    NASA Astrophysics Data System (ADS)

    Swiatlowski, Jerlyn; Palm, Christopher; Joshi, Trinity; Montcrieffe, Caitlin; Jackson Kimball, Derek

    2013-05-01

    We discuss progress in our experimental program to employ optical-frequency-comb-based spectroscopy to understand the complex spectra of rare-earth atoms. We plan to carry out systematic measurements of atomic transitions in rare-earth atoms to elucidate the energy level structure and term assignment and determine presently unknown atomic state parameters. This spectroscopic information is important in view of the increasing interest in rare-earth atoms for atomic frequency standards, in astrophysical investigations of chemically peculiar stars, and in tests of fundamental physics (tests of parity and time-reversal invariance, searches for time variation of fundamental constants, etc.). We are presently studying the use of hollow cathode lamps as atomic sources for two-photon frequency comb spectroscopy. Supported by the National Science Foundation under grant PHY-0958749.

  19. Discovery of Rare Mutations in Autism: Elucidating Neurodevelopmental Mechanisms.

    PubMed

    Gamsiz, Ece D; Sciarra, Laura N; Maguire, Abbie M; Pescosolido, Matthew F; van Dyck, Laura I; Morrow, Eric M

    2015-07-01

    Autism spectrum disorder (ASD) is a group of highly genetic neurodevelopmental disorders characterized by language, social, cognitive, and behavioral abnormalities. ASD is a complex disorder with a heterogeneous etiology. The genetic architecture of autism is such that a variety of different rare mutations have been discovered, including rare monogenic conditions that involve autistic symptoms. Also, de novo copy number variants and single nucleotide variants contribute to disease susceptibility. Finally, autosomal recessive loci are contributing to our understanding of inherited factors. We will review the progress that the field has made in the discovery of these rare genetic variants in autism. We argue that mutation discovery of this sort offers an important opportunity to identify neurodevelopmental mechanisms in disease. The hope is that these mechanisms will show some degree of convergence that may be amenable to treatment intervention. PMID:26105128

  20. Halos in cirrus clouds: why are classic displays so rare?

    PubMed

    Sassen, Kenneth

    2005-09-20

    Upper tropospheric cirrus clouds consist of hexagonal ice crystals, which geometrical ray-tracing-theory predicts should regularly produce a variety of optical phenomena such as vivid 22 degrees and 46 degrees halos. Yet, cirrus inconsistently generate such optical displays, while a class of more exotic displays are reported, albeit rarely. I review current knowledge of the cirrus cloud microphysical factors that control ice crystal shape, and hence halo/arc formation, but also appeal to halo enthusiasts to help investigate the causes of unusually complex, brilliant, or rare optical displays. Currently, a wealth of meteorological information can be tapped from the Internet to help advance our knowledge of the basic meteorological factors leading to these rare events. PMID:16201430

  1. Maxillofacial esthesioneuroblastoma: A diagnostic complexity

    PubMed Central

    Raj, G Shyam; Rao, Guttikonda Venkateswara; Kumar, Manchikatla Praveen; Sudheerkanth, Kondamari

    2016-01-01

    Esthesioneuroblastoma is a rare malignant tumor of the sinonasal tract. Oral and maxillofacial pathologists rarely encounter this tumor in their daily practice. Because of their complex anatomic location, non-specific symptoms, varied histomorphology and unfamiliarity, most of the times, the tumor is diagnosed as benign tumor and thereby conservative treatment results in multiple recurrences. A recurrent case of esthesioneuroblastoma in a 24-year-old female patient describing the clinical, histopathological and immunohistochemical features along with differential diagnosis is discussed. PMID:27601839

  2. Maxillofacial esthesioneuroblastoma: A diagnostic complexity.

    PubMed

    Raj, G Shyam; Rao, Guttikonda Venkateswara; Kumar, Manchikatla Praveen; Sudheerkanth, Kondamari

    2016-01-01

    Esthesioneuroblastoma is a rare malignant tumor of the sinonasal tract. Oral and maxillofacial pathologists rarely encounter this tumor in their daily practice. Because of their complex anatomic location, non-specific symptoms, varied histomorphology and unfamiliarity, most of the times, the tumor is diagnosed as benign tumor and thereby conservative treatment results in multiple recurrences. A recurrent case of esthesioneuroblastoma in a 24-year-old female patient describing the clinical, histopathological and immunohistochemical features along with differential diagnosis is discussed. PMID:27601839

  3. Rare Tumors in Children: Progress Through Collaboration

    PubMed Central

    Furman, Wayne L.; Schultz, Kris A.; Ferrari, Andrea; Helman, Lee; Krailo, Mark D.

    2015-01-01

    Rare pediatric tumors account for approximately 10% of all childhood cancers, which in themselves are a rare entity. The diverse histologies and clinical behaviors of rare pediatric tumors pose challenges to the investigation of their biologic and clinical features. National and international cooperative groups such as the Rare Tumor Committee of the Children's Oncology Group, Rare Tumors in Pediatric Age Project, and European Cooperative Study Group for Pediatric Rare Tumors have developed several initiatives to advance knowledge about rare pediatric cancers. However, these programs have been only partially effective, necessitating the development of alternative mechanisms to study these challenging diseases. In this article, we review the current national and international collaborative strategies to study rare pediatric cancers and alternative methods under exploration to enhance those efforts, such as independent registries and disease-specific, National Cancer Institute–sponsored clinics. PMID:26304909

  4. Genetic and Rare Diseases Information Center

    MedlinePlus

    ... GARD Information Specialists can provide you with current, reliable, and easy to understand information about rare or ... GARD provides the public with access to current, reliable, and easy-to-understand information about rare or ...

  5. Hopes Dashed for Rare Bone Cancer Treatment

    MedlinePlus

    ... news/fullstory_160652.html Hopes Dashed for Rare Bone Cancer Treatment Extra chemo drugs failed to change course ... t benefit patients with a rare type of bone cancer, according to a new study. Osteosarcoma is diagnosed ...

  6. The study of rare decays

    NASA Astrophysics Data System (ADS)

    Ju, Wan-Li; Wang, Guo-Li; Fu, Hui-Feng; Wang, Tian-Hong; Jiang, Yue

    2014-04-01

    In this paper, we study rare decays within the Standard Model. The penguin, box, annihilation, color-favored cascade and color-suppressed cascade contributions are included. Based on our calculation, the annihilation and color-favored cascade diagrams play important roles in the differential branching fractions, forward-backward asymmetries, longitudinal polarizations of the final vector mesons and leptonic longitudinal polarization asymmetries. More importantly, color-favored cascade decays largely enhance the resonance cascade contributions. To avoid the resonance cascade contribution pollution, new cutting regions are put forward.

  7. Esophageal Lipoma: A Rare Tumor

    PubMed Central

    Feldman, Jeremy; Tejerina, Manfred; Hallowell, Michael

    2012-01-01

    Esophageal lipomas are rare tumors, making up 0.4% of all digestive tract benign neoplasms. Most of these lesions are clinically silent as a result of their small size, however, the majority of lesions over 4 cm have been reported to cause dysphagia, regurgitation and/or epigastralgia. We report a case of a 53 year-old African American female who presented with dysphagia. Computed tomography of the chest and esophagram confirmed esophageal lipoma as the cause of the patient’s symptoms. Accurately diagnosing an esophageal lipoma is crucial in order to rule out potential malignant lesions, relieve patient symptoms and plan the appropriate treatment. PMID:23365708

  8. Parasitic and rare spinal infections.

    PubMed

    do Amaral, Lázaro Luís Faria; Nunes, Renato Hoffmann; da Rocha, Antonio Jose

    2015-05-01

    The imaging features of spinal parasitic diseases and other rare infections are herein discussed. These diseases are distributed worldwide, with increased prevalence in areas with poor sanitary conditions and in developing countries. In nonendemic areas, sporadic cases may occur, consequent to increased international travel and immunocompromising conditions. Infectious diseases are usually treatable, and early detection is often crucial. A thorough comprehension of the imaging patterns associated with the clinical features, epidemiology, and laboratory results allows the radiologist to narrow down the options for differential diagnosis and facilitates the timely implementation of appropriate therapies. PMID:25952177

  9. Rare emerging malignant skin tumours.

    PubMed

    Rongioletti, F; Ferreli, C; Pinna, A L; Atzori, L

    2015-08-01

    As clinical skills improve and innovative diagnostic techniques become available in the field of dermatology and dermatopathology, new types or additional variants of malignant skin tumors are described. This article reviews the current nomenclature, clinico-pathological features, differential diagnosis, prognostic and therapeutic implications of some new dermato(patho)logical rare emerging skin tumors, including epithelial tumors (squamous cell carcinoma with mucinous metaplasia), adnexal tumors (endocrine mucin-producing sweat gland carcinoma), soft tissue tumors of vascular differentiation (pseudolymphomatous cutaneous angiosarcoma, pseudomyogenic hemangioendothelioma), hematopoietic tumors (blastic plasmacytoid dendritic cell neoplasm) and mixed epithelial/melanocytic tumor (squamomelanocytic tumor). PMID:26086411

  10. Identifying rare variants from exome scans: the GAW17 experience

    PubMed Central

    2011-01-01

    Genetic Analysis Workshop 17 (GAW17) provided a platform for evaluating existing statistical genetic methods and for developing novel methods to analyze rare variants that modulate complex traits. In this article, we present an overview of the 1000 Genomes Project exome data and simulated phenotype data that were distributed to GAW17 participants for analyses, the different issues addressed by the participants, and the process of preparation of manuscripts resulting from the discussions during the workshop. PMID:22373325