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Will Kew, Ian Goodall, David Clarke, Dušan Uhrín
Scotch Whisky is an important product, both culturally and economically. Chemically, Scotch Whisky is a complex mixture, which comprises thousands of compounds, the nature of which are largely unknown. Here, we present a thorough overview of the chemistry of Scotch Whisky as observed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Eighty-five whiskies, representing the majority of Scotch Whisky produced and sold, were analyzed by untargeted high-resolution mass spectrometry. Thousands of chemical formulae were assigned for each sample based on parts-per-billion mass accuracy of FT-ICR MS spectra...
October 17, 2016: Journal of the American Society for Mass Spectrometry
Kiichi Ishiwata, Kunpei Hayashi, Masanari Sakai, Sugio Kawauchi, Hideaki Hasegawa, Jun Toyohara
OBJECTIVE: To elucidate the radionuclides and radiochemical impurities included in radiosynthesis processes of positron emission tomography (PET) tracers. METHODS: Target materials and PET tracers were produced using a cyclotron/synthesis system from Sumitomo Heavy Industry. Positron and γ-ray emitting radionuclides were quantified by measuring radioactivity decay and using the high-purity Ge detector, respectively. Radiochemical species in gaseous and aqueous target materials were analyzed by gas and ion chromatography, respectively...
October 15, 2016: Annals of Nuclear Medicine
Yu Tang, Shuntao Li, Yuanyou Yang, Wen Chen, Hongyuan Wei, Guanquan Wang, Jijun Yang, Jiali Liao, Shunzhong Luo, Ning Liu
A simple and convenient method for radiochemical separation (89)Zr with no harmful substance was explored. The separated (89)Zr was found to be [(89)Zr]Zr-chloride, and the recovery of the radioactivity was 85%±3% with high radionuclidic purity (99.99%). The yields of (89)Zr via the reaction of (p, n) or (d, 2n) on Y target were also evaluated on CS-30 cyclotron, indicating the latter was more favorable for the production of (89)Zr with a yield of 58±4 MBq/μA·h.
September 26, 2016: Applied Radiation and Isotopes
Petra Martini, Alessandra Boschi, Gianfranco Cicoria, Licia Uccelli, Micòl Pasquali, Adriano Duatti, Gaia Pupillo, Mario Marengo, Massimo Loriggiola, Juan Esposito
The design and fabrication of a fully-automated, remotely controlled module for the extraction and purification of technetium-99m (Tc-99m), produced by proton bombardment of enriched Mo-100 molybdenum metallic targets in a low-energy medical cyclotron, is here described. After dissolution of the irradiated solid target in hydrogen peroxide, Tc-99m was obtained under the chemical form of (99m)TcO4(-), in high radionuclidic and radiochemical purity, by solvent extraction with methyl ethyl ketone (MEK). The extraction process was accomplished inside a glass column-shaped vial especially designed to allow for an easy automation of the whole procedure...
October 5, 2016: Applied Radiation and Isotopes
Svetlana Selivanova, Éric Lavallée, Helena Senta, Lyne Caouette, Alexander Jb McEwan, Brigitte Guérin, Roger Lecomte, Eric Turcotte
: A single-site prospective open-label clinical study with cyclotron-produced sodium pertechnetate (99m)Tc ([(99m)Tc]NaTcO4, (99m)Tc-pertechnetate) was performed in patients with indication for a thyroid scan to demonstrate the clinical safety and diagnostic efficacy of the drug and confirm its equivalence with conventional sodium pertechnetate (99m)Tc eluted from a generator. METHODS: Sodium pertechnetate (99m)Tc was produced with a cyclotron (24 MeV, 2 h irradiation) from enriched 100Mo (99...
October 13, 2016: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
Anna C Susa, Zijie Xia, Henry Y H Tang, John A Tainer, Evan R Williams
Factors that influence the charging of protein ions formed by electrospray ionization from aqueous solutions in which proteins have native structures and function were investigated. Protein ions ranging in molecular weight from 12.3 to 79.7 kDa and pI values from 5.4 to 9.6 were formed from different solutions and reacted with volatile bases of gas-phase basicities higher than that of ammonia in the cell of a Fourier-transform ion cyclotron resonance mass spectrometer. The charge-state distribution of cytochrome c ions formed from aqueous ammonium or potassium acetate is the same...
October 12, 2016: Journal of the American Society for Mass Spectrometry
Jared B Shaw, Tzu-Yung Lin, Franklin E Leach, Aleksey V Tolmachev, Nikola Tolić, Errol W Robinson, David W Koppenaal, Ljiljana Paša-Tolić
We provide the initial performance evaluation of a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer operating at the Environmental Molecular Sciences Laboratory at the Pacific Northwest National Laboratory. The spectrometer constructed for the 21T system employs a commercial dual linear ion trap mass spectrometer coupled to a FTICR spectrometer designed and built in-house. Performance gains from moving to higher magnetic field strength are exemplified by the measurement of peptide isotopic fine structure, complex natural organic matter mixtures, and large proteins...
October 12, 2016: Journal of the American Society for Mass Spectrometry
Fabian Cantu Reinhard, Mala Sainna, Pranav Upadhayay, Alex Balan, Devesh Kumar, Simonetta Fornarini, Maria Elisa Crestoni, Samuel de Visser
Cytochrome P450 enzymes are heme containing mono-oxygenases that mainly react through oxygen atom transfer. Specific features of substrate and oxidant that determine the reaction rate constant for oxygen atom transfer are still poorly understood and, therefore, we did a systematic gas-phase study on reactions by iron(IV)-oxo porphyrin cation radical structures with arenes. We present here the first results obtained by using Fourier transform-ion cyclotron resonance mass spectrometry and provide rate constants and product distributions for the assayed reactions...
October 11, 2016: Chemistry: a European Journal
Tran Thi Hong Hanh, Le Thi Vien, Le Ba Vinh, Nguyen Van Thanh, Nguyen Xuan Cuong, Nguyen Hoai Nam, Do Cong Thung, Phan Van Kiem, Chau Van Minh
Eight highly hydroxylated steroids (1-8), including three new compounds as sodium salts of (24S)-5α-cholestane-3β,4β,5,6α,7β,8,14,15α,24-nonaol 6-sulfate (1), (24E)-5α-cholest-24-ene-26-yde-3β,6α,8,14,15α-pentaol 15-sulfate (2), and 5α-cholest-3β,6α,8,14,15α,24,25,26-octaol 15-sulfate (3), were isolated and elucidated from the methanol extract of the Vietnamese starfish Archaster typicus. The structure elucidation was done by spectroscopic methods including one and two dimensional (1D-, 2D-)NMR and Fourier transform ion cyclotron resonance (FT-ICR)-MS...
2016: Chemical & Pharmaceutical Bulletin
Małgorzata Wrzesień, Łukasz Albiniak
(18)F-FDG is the most popular radiopharmaceutical used, among others, in oncological diagnostics by PET technique. The production of (18)F-FDG is a multistep process that begins by obtaining the radioisotope (18)F, and subsequently labelling the radiopharmaceutical, as well as quality control of the resulting compound. In each of these stages, the employee has contact with ionizing radiation. The production of (18)F requires the use of a cyclotron device. Currently in Poland, there are 9 centres equipped with a cyclotron for the production of positron-emitting radioisotopes...
October 11, 2016: Journal of Radiological Protection: Official Journal of the Society for Radiological Protection
J Konheiser, B Naumann, A Ferrari, C Brachem, S E Müller
Calculations of the shielding and estimates of soil activation for a medical cyclotron are presented in this work. Based on the neutron source term from the (18)O(p,n)(18)F reaction produced by a 28 MeV proton beam, neutron and gamma dose rates outside the building were estimated with the Monte Carlo code MCNP6 (Goorley et al 2012 Nucl. Technol. 180 298-315). The neutron source term was calculated with the MCNP6 code and FLUKA (Ferrari et al 2005 INFN/TC_05/11, SLAC-R-773) code as well as with supplied data by the manufacturer...
October 11, 2016: Journal of Radiological Protection: Official Journal of the Society for Radiological Protection
C Duchemin, A Guertin, F Haddad, N Michel, V Métivier
Several terbium isotopes are suited for diagnosis or therapy in nuclear medicine. Tb-155 is of interest for SPECT imaging and/or Auger therapy. High radionuclide purity is mandatory for many applications in medicine. The quantification of the activity of the produced contaminants is therefore as important as that of the radionuclide of interest. The experiments performed at the ARRONAX cyclotron (Nantes, France), using the deuteron beam delivered up to 34MeV, provide an additional measurement of the excitation function of the Gd-nat(d,x)Tb-155 reaction and of the produced terbium and gadolinium contaminants...
September 30, 2016: Applied Radiation and Isotopes
Li Zhang, Shengrui Wang, Yisheng Xu, Quan Shi, Haichao Zhao, Bin Jiang, Jiachun Yang
The compositional properties of water-extractable organic nitrogen (WEON) affect its behavior in lake ecosystems. This work is the first comprehensive study using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) for the characterization of the molecular composition of WEON in lake sediment. In sediments of Erhai Lake in China, this study found complex WEON species, with N-containing compounds in the northern, central, and southern regions contributing 34.47%, 42.44%, and 40.6%, respectively, of total compounds...
September 28, 2016: Water Research
A Akrap, M Hakl, S Tchoumakov, I Crassee, J Kuba, M O Goerbig, C C Homes, O Caha, J Novák, F Teppe, W Desrat, S Koohpayeh, L Wu, N P Armitage, A Nateprov, E Arushanov, Q D Gibson, R J Cava, D van der Marel, B A Piot, C Faugeras, G Martinez, M Potemski, M Orlita
We report on optical reflectivity experiments performed on Cd_{3}As_{2} over a broad range of photon energies and magnetic fields. The observed response clearly indicates the presence of 3D massless charge carriers. The specific cyclotron resonance absorption in the quantum limit implies that we are probing massless Kane electrons rather than symmetry-protected 3D Dirac particles. The latter may appear at a smaller energy scale and are not directly observed in our infrared experiments.
September 23, 2016: Physical Review Letters
Menyoung Lee, John R Wallbank, Patrick Gallagher, Kenji Watanabe, Takashi Taniguchi, Vladimir I Fal'ko, David Goldhaber-Gordon
Rational design of long-period artificial lattices yields effects unavailable in simple solids. The moiré pattern in highly aligned graphene/hexagonal boron nitride (h-BN) heterostructures is a lateral superlattice with high electron mobility and an unusual electronic dispersion whose miniband edges and saddle points can be reached by electrostatic gating. We investigated the dynamics of electrons in moiré minibands by measuring ballistic transport between adjacent local contacts in a magnetic field, known as the transverse electron focusing effect...
September 30, 2016: Science
Pablo Nieto, Alan Günther, Giel Berden, Jos Oomens, Otto Dopfer
Flavins are a fundamental class of biomolecules, whose photochemical properties strongly depend on their environment and their redox and metalation state. Infrared multiphoton dissociation (IRMPD) spectra of mass selected isolated metal-lumiflavin ionic complexes (M+LF) are analyzed in the fingerprint range (800-1830 cm-1) to determine the bonding of lumiflavin with alkali (M=Li, Na, K, Cs) and coinage (M=Cu, Ag) metal ions. The complexes are generated in an electrospray ionization source coupled to an ion cyclotron resonance mass spectrometer and the IR free electron laser FELIX...
October 1, 2016: Journal of Physical Chemistry. A
A R Liboff, Claudio Poggi, Piero Pratesi
Recent observations of low-frequency electromagnetic oscillations in water suggest an inductive structural component. Accordingly, we assume a helical basis enabling us to model water as an LC tuned oscillator. A proposed tetrahedral structure consisting of three water molecules and one hydronium ion is incorporated into the Boerdijk-Coxeter tetrahelix to form long water chains that are shown to have resonance frequencies consistent with observation. This model also serves to explain separately reported claims of ion cyclotron resonance of hydronium ions, in that the tetrahelix provides a built-in path for helical proton-hopping...
September 29, 2016: Electromagnetic Biology and Medicine
Junling Ren, Dan Zhang, Yujie Liu, Ruiqing Zhang, Huiling Fang, Shuai Guo, Dan Zhou, Mo Zhang, Yupin Xu, Ling Qiu, Zhili Li
In this study, we have employed graphene oxide as a matrix to simultaneously and directly quantify serum nonesterified and esterified fatty acids (FAs) using matrix-assisted laser/desorption ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS). Twelve serum nonesterified FAs combined with their individual esterified FAs (i.e., C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:2, C20:3, C20:4, C20:5, C22:5, and C22:6) were quantified based on their calibration curves with the correlation coefficients of >0...
September 30, 2016: Scientific Reports
Anand Bhattacharya, Brian Skinner, Guru Khalsa, Alexey V Suslov
When an electronic system is subjected to a sufficiently strong magnetic field that the cyclotron energy is much larger than the Fermi energy, the system enters the extreme quantum limit (EQL) and becomes susceptible to a number of instabilities. Bringing a three-dimensional electronic system deeply into the EQL can be difficult however, since it requires a small Fermi energy, large magnetic field, and low disorder. Here we present an experimental study of the EQL in lightly-doped single crystals of strontium titanate...
2016: Nature Communications
Marina Hodolic, Raffi Topakian, Robert Pichler
BACKGROUND: Epilepsy is a neurological disorder characterized by epileptic seizures as a result of excessive neuronal activity in the brain. Approximately 65 million people worldwide suffer from epilepsy; 20-40% of them are refractory to medication therapy. Early detection of disease is crucial in the management of patients with epilepsy. Correct localization of the ictal onset zone is associated with a better surgical outcome. The modern non-invasive techniques used for structural-functional localization of the seizure focus includes electroencephalography (EEG) monitoring, magnetic resonance imaging (MRI), single photon emission tomography/computed tomography (SPECT/CT) and positron emission tomography/computed tomography (PET/CT)...
September 1, 2016: Radiology and Oncology
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