Read by QxMD icon Read


Urs B Hagemann, Dessislava Mihaylova, Steinar R Uran, Joergen Borrebaek, Derek Grant, Roger M Bjerke, Jenny Karlsson, Alan S Cuthbertson
The cell surface receptor CD70 has been previously reported as a promising target for B-cell lymphomas and several solid cancers including renal cell carcinoma. We describe herein the characterization and efficacy of a novel CD70 targeted thorium-227 conjugate (CD70-TTC) comprising the combination of the three components, a CD70 targeting antibody, a chelator moiety and the short-range, high-energy alpha-emitting radionuclide thorium-227 ((227)Th). In vitro analysis demonstrated that the CD70-TTC retained binding affinity to its target and displayed potent and specific cytotoxicity compared to an isotype control-TTC...
August 22, 2017: Oncotarget
Tara R Clark, George Roff, Jian-Xin Zhao, Yue-Xing Feng, Terence J Done, Laurence J McCook, John M Pandolfi
Hard coral cover on the Great Barrier Reef (GBR) is on a trajectory of decline. However, little is known about past coral mortality before the advent of long-term monitoring (circa 1980s). Using paleoecological analysis and high-precision uranium-thorium (U-Th) dating, we reveal an extensive loss of branching Acropora corals and changes in coral community structure in the Palm Islands region of the central GBR over the past century. In 2008, dead coral assemblages were dominated by large, branching Acropora and living coral assemblages by genera typically found in turbid inshore environments...
September 11, 2017: Proceedings of the National Academy of Sciences of the United States of America
Mary E Garner, Bernard F Parker, Stephan Hohloch, Robert G Bergman, John Arnold
The bis(NHC)borate-supported thorium-bis(mesitylphosphido) complex (1) undergoes reversible intramolecular C-H bond activation enabling the catalytic hydrophosphination of unactivated internal alkynes. Catalytic and stoichiometric experiments support a mechanism involving reactive Th-NHC metallacycle intermediates (Int and 2).
September 11, 2017: Journal of the American Chemical Society
Pokpong Rungthanaphatsophon, Adrien Bathelier, Ludovic Castro, Andrew C Behrle, Charles L Barnes, Laurent Maron, Justin R Walensky
The reaction of (C5 Me5 )2 Th(CH3 )2 with the phosphonium salts [CH3 PPh3 ]X (X=Cl, Br, I) was investigated. When X=Br and I, two equivalents of methane are liberated to afford (C5 Me5 )2 Th[CHPPh3 ]X, rare terminal phosphorano-stabilized carbenes with thorium. These complexes feature the shortest thorium-carbon bonds (≈2.30 Å) reported to date, and electronic structure calculations show some degree of multiple bonding. However, when X=Cl, only one equivalent of methane is lost with concomitant formation of benzene from an unstable phosphorus(V) intermediate, yielding (C5 Me5 )2 Th[κ(2) -(C,C')-(CH2 )(CH2 )PPh2 ]Cl...
September 7, 2017: Angewandte Chemie
Carlos Pérez-Mejías, Ana Moreno, Carlos Sancho, Miguel Bartolomé, Heather Stoll, Isabel Cacho, Hai Cheng, R Lawrence Edwards
The Late Quaternary glacial-interglacial transitions represent the highest amplitude climate changes over the last million years. Unraveling the sequence of events and feedbacks at Termination III (T-III), including potential abrupt climate reversals similar to those of the last Termination, has been particularly challenging due to the scarcity of well-dated records worldwide. Here, we present speleothem data from southern Europe covering the interval from 262.7 to 217.9 kyBP, including the transition from marine isotope stage (MIS) 8 to MIS 7e...
September 5, 2017: Proceedings of the National Academy of Sciences of the United States of America
Ning Pan, Long Li, Jie Ding, Ruibing Wang, Yongdong Jin, Chuanqin Xia
A novel approach for facile covalent functionalization of graphene oxide (GO) was proposed in the present study in order to effectively avoid necessary anhydrous conditions and the usage of harsh reagents during the chemical functionalization of GO. Herein, a GO derivative that was functionalized with a primary amine derivative bearing a positively charged quaternary ammonium group, GO-S, was synthesized through a Schiff base condensation reaction between the amine groups of the primary amine derivative and the aldehyde groups of GO...
August 22, 2017: Journal of Colloid and Interface Science
Valery Radchenko, Tara Mastren, Catherine A L Meyer, Alexander S Ivanov, Vyacheslav S Bryantsev, Roy Copping, David Denton, Jonathan W Engle, Justin R Griswold, Karen Murphy, Justin J Wilson, Allison Owens, Lance Wyant, Eva R Birnbaum, Jonathan Fitzsimmons, Dmitri Medvedev, Cathy S Cutler, Leonard F Mausner, Meiring F Nortier, Kevin D John, Saed Mirzadeh, Michael E Fassbender
Actinium-225 is a potential Targeted Alpha Therapy (TAT) isotope. It can be generated with high energy (≥ 100MeV) proton irradiation of thorium targets. The main challenge in the chemical recovery of (225)Ac lies in the separation from thorium and many fission by-products most importantly radiolanthanides. We recently developed a separation strategy based on a combination of cation exchange and extraction chromatography to isolate and purify (225)Ac. In this study, actinium and lanthanide equilibrium distribution coefficients and column elution behavior for both TODGA (N,N,N',N'-tetra-n-octyldiglycolamide) and TEHDGA (N,N,N',N'-tetrakis-2-ethylhexyldiglycolamide) were determined...
December 1, 2017: Talanta
Matthew A Stuber, Anna Y Kornienko, Thomas J Emge, John G Brennan
Tetrametallic thorium compounds with a Th4E4 core (E = S, Se) having a distorted cubane structure can be prepared by ligand-based reductions of elemental E with thorium chalcogenolates, prepared by in situ oxidation of Th metal with a 3:1 mixture of PhEEPh and F5C6EEC6F5. Four compounds, (py)8Th4S4(μ2-SPh)4(SC6F5)4, (py)8Th4S4(μ2-SPh)4(SeC6F5)4, (py)8Th4Se4(μ2-SePh)4(SeC6F5)4, and (py)8Th4Se4(μ2-SePh)4(SC6F5)4, were isolated and characterized by NMR spectroscopy and X-ray diffraction. These compounds clearly demonstrate the chemical impact of ring fluorination, with the less-nucleophilic EC6F5 ligands occupying the terminal binding sites and the EPh ligands bridging two metal centers...
August 23, 2017: Inorganic Chemistry
Stephan Hohloch, James R Pankhurst, Esther E Jaekel, Bernard F Parker, Daniel J Lussier, Mary E Garner, Corwin H Booth, Jason B Love, John Arnold
We report the coordination chemistry of the tripodal tris[2-amido(2-pyridyl)ethyl]amine ligand, L, with thorium(iv) and uranium(iv). Using a salt-metathesis strategy from the potassium salt of this ligand, K3L, new actinide complexes were isolated, namely the dimeric thorium complex [ThCl(L)]2 (1) and the monomeric uranium complex UI(THF)(L) (2); under different crystallisation conditions, the dimeric uranium complex is also isolated, [UI(L)]2 (2-dimer). With the aim of studying electronic phenomena such as magnetic exchange between two actinide ions, we have synthesised the first examples of dinuclear, quinoid-bridged actinide complexes from dianionic 2,5-bis[2,6-(diisopropyl)anilide]-1,4-benzoquinone (QDipp) and 2,5-bis[2-(methoxy)anilide]-1,4-benzoquinone (QOMe) ligands...
September 12, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
S Skanthakumar, Geng Bang Jin, Jian Lin, Valérie Vallet, L Soderholm
Seeking predictive insights into how metal-ion speciation impacts solution chemistry as well as the composition and structure of solid-precipitates, thorium correlations, with both solvent and other solute ions, were quantitatively probed in a series of acidic, nitrate/perchlorate solutions held at constant ionic strength. Difference pair-distribution functions (dPDF), obtained from high-energy X-ray scattering (HEXS) data, provide unprecedented structural information on the number of Th ligating ions in solution and how they change with increasing nitrate concentration...
August 30, 2017: Journal of Physical Chemistry. B
Tara Mastren, Valery Radchenko, Allison Owens, Roy Copping, Rose Boll, Justin R Griswold, Saed Mirzadeh, Lance E Wyant, Mark Brugh, Jonathan W Engle, Francois M Nortier, Eva R Birnbaum, Kevin D John, Michael E Fassbender
A new method has been developed for the isolation of (223,224,225)Ra, in high yield and purity, from a proton irradiated (232)Th matrix. Herein we report an all-aqueous process using multiple solid-supported adsorption steps including a citrate chelation method developed to remove >99.9% of the barium contaminants by activity from the final radium product. A procedure involving the use of three columns in succession was developed, and the separation of (223,224,225)Ra from the thorium matrix was obtained with an overall recovery yield of 91 ± 3%, average radiochemical purity of 99...
August 15, 2017: Scientific Reports
Malika Denis, Timo Fleig
We present an updated electron electric dipole moment (EDM) effective electric field of Eeff= 75.2 GV/cm and (229)Th magnetic hyperfine interaction constant A|| = -1266 MHz, the nucleon-electron scalar-pseudoscalar interaction constant WS = 106.0 kHz, and the molecule-frame static electric dipole moment D = -4.41 D for the Δ13 science state of ThO. The criticisms of the results from Fleig and Nayak [J. Mol. Spectrosc. 300, 16 (2014)] made in Skripnikov and Titov [J. Chem. Phys. 142, 024301 (2015)] are addressed and largely found to be unsubstantiated within the framework of the present approach...
December 7, 2016: Journal of Chemical Physics
K A Erickson, B D Kagan, B L Scott, D E Morris, J L Kiplinger
The reaction of (C5Me5)2AnCl2 (An = Th, U) with 2.8 or 4 equivalents of LiNMe2, respectively, affords (C5Me5)2An(NMe2)2 in high yields. In addition to improved syntheses, the solid-state structures, voltammetric data, and UV-visible-NIR spectra for these classic actinide bis(dimethylamido) complexes are presented for the first time.
August 29, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Geng Bang Jin, Christos D Malliakas, Jian Lin
To explore the chemical analogy between thorium and heavier actinides in soft anionic environments, three new thorium phosphides (ThCuP2, β-ThCu2P2, and ThCu5P3) have been prepared through solid-state reactions using CuI as a reaction promoter. The structure of ThCuP2 can be described as a filled UTe2-type with both dimeric P2(4-) and monomeric P(3-) anions, in which Th is coordinated by eight P atoms in a bicapped trigonal prismatic arrangement and Cu is tetrahedrally coordinated by four P atoms. β-ThCu2P2 contains only P(3-) anions and is isostructural with BaCu2S2...
September 28, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Maria Sotiropoulou, Heleny Florou, Georgios Kitis
The substantial complexity in ecosystem-radionuclide interactions is difficult to be represented in terms of radiological doses. Thus, radiological dose assessment tools use typical exposure situations for generalized organisms and ecosystems. In the present study, site-specific data and radioactivity measurements of terrestrial organisms (grass and herbivore mammals) and abiotic components (soil) are provided. The retrieved data are used in combination with the ERICA Assessment Tool for calculation of radiological parameters...
August 3, 2017: Radiation and Environmental Biophysics
E M El Afifi, A M Shahr El-Din, R F Aglan, E H Borai, M M Abo-Aly
Egyptian monazite is a promising resource and investment attractive for production of valuable metals of industrial or nuclear interest such as rare earth elements (REEs), thorium (Th) and uranium (U). The study was focused to establish a baseline framework in viewpoint of radiation protection for the workers in production of REEs from high-grade monazite treated by sodium hydroxide (NaOH) solutions. Radiological hazard indices (cancer, gonadal and other risks) were evaluated, due to emissions (α-, β- and γ-radiations) of radium-isotopes ((228)Ra, (226)Ra, (223)Ra) and lead ((210)Pb)...
July 29, 2017: Regulatory Toxicology and Pharmacology: RTP
M Vasile, K Jacobs, M Bruggeman, K Van Hoecke, A Dobney, F Verrezen
The implementation of the one-pass-through separation technique using two stacked chromatography columns of TEVA - TRU resins for the separation of (237)Np, (241)Am, thorium, plutonium and uranium from environmental and urine samples was investigated. The sequential separation technique proved to be successful and gave similar results to those obtained when using individual separations. The analysis time was considerably improved. The amount of chemical waste was also reduced by 50% and the use of HClO4 was avoided...
July 13, 2017: Applied Radiation and Isotopes
Marco Kaltofen, Arnie Gundersen
After the March 11, 2011, nuclear reactor meltdowns at Fukushima Dai-ichi, 180 samples of Japanese particulate matter (dusts and surface soils) and 235 similar U.S. and Canadian samples were collected and analyzed sequentially by gamma spectrometry, autoradiography, and scanning electron microscopy with energy dispersive X-ray analysis. Samples were collected and analyzed over a five-year period, from 2011 to 2016. Detectable levels of (134)Cs and (137)Cs were found in 142 of 180 (80%) Japanese particulate matter samples...
December 31, 2017: Science of the Total Environment
Manuel Alcaraz-Castaño, Javier Alcolea-González, Martin Kehl, Rosa-María Albert, Javier Baena-Preysler, Rodrigo de Balbín-Behrmann, Felipe Cuartero, Gloria Cuenca-Bescós, Fernando Jiménez-Barredo, José-Antonio López-Sáez, Raquel Piqué, David Rodríguez-Antón, José Yravedra, Gerd-Christian Weniger
INTRODUCTION AND OBJECTIVES: Although the Iberian Peninsula is a key area for understanding the Middle to Upper Paleolithic transition and the demise of the Neandertals, valuable evidence for these debates remains scarce and problematic in its interior regions. Sparse data supporting a late Neandertal persistence in the Iberian interior have been recently refuted and hence new evidence is needed to build new models on the timing and causes of Neandertal disappearance in inland Iberia and the whole peninsula...
2017: PloS One
Nan Zhang, Li-Yong Yuan, Wen-Lu Guo, Shi-Zhong Luo, Zhi-Fang Chai, Wei-Qun Shi
Thorium separation has recently become a hot topic because of the potential application of thorium as a future nuclear fuel, while metal-organic framework (MOF) materials have received much attention in the separation field due to their unique properties. Herein, a highly porous and stable MOF, UiO-66, and its carboxyl derivatives (UiO-66-COOH and UiO-66-(COOH)2) were synthesized and explored for the first time for Th(IV) capture from a weak acidic solution. Although the introduction of carboxyl groups into UiO-66 leads to an obvious decrease in the surface area and pore volume, the adsorbability toward Th(IV) is greatly enhanced...
July 19, 2017: ACS Applied Materials & Interfaces
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"