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141.
Vadim A. Babkin Gheorghe Cata-Danil Viacheslav M. Golovatyuk Aleksandr G. Molokanov Mihaela M. Paraipan Gennady N. Timoshenko 《Central European Journal of Physics》2010,8(4):683-688
A ridge carbon beam filter for Spreading Out the Bragg Peak (SOBP) up to 20 mm in the targeted area has been designed and experimentally tested. The instrument was constructed of Plexiglas with a density of 1.165 g/cm3 and has a “teeth” structure with a period of 2.5 mm. The design is based on a simple analytical model and detailed GEANT4 Monte Carlo simulations. In-beam test measurements were performed with a 500-MeV/u 12C beam at the Nuclotron facility of the Joint Institute for Nuclear Research (JINR) in Dubna. The filter can be used as a static device positioned in front of patients undergoing carbon therapy. 相似文献
142.
Corrigendum: Composite Aromatic Boxes for Enzymatic Transformations of Quaternary Ammonium Substrates
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143.
Kevin Lamberts Mihaela‐Diana erb Ulli Englert 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):271-275
In catena‐poly[copper(II)‐di‐μ‐chlorido‐μ‐proline‐κ2O:O′], [CuCl2(C5H9NO2)]n, two symmetry‐independent metal cations adopt distorted octahedral coordination, typical for d9 Jahn–Teller systems. Each chloride bridge is involved in both a short and a very long interaction with a CuII centre. The centrosymmetric crystal structure contains homochiral chains of opposite handedness which extend along the shortest lattice parameter (i.e. a). The O:O′‐bridging coordination mode of proline, although a common motif for such complexes in general, is remarkable for CuII; the vast majority of amino acid derivatives of this cation are characterized by N,O‐chelation. 相似文献
144.
Victor Constantin Diculescu Teodor Adrian Enache Paulo Jorge Oliveira Ana Maria Oliveira‐Brett 《Electroanalysis》2010,22(1):113-120
The electrochemical behavior of sanguinarine, a quaternary benzophenanthridine glycoside alkaloid with antimicrobial, anti‐inflammatory, antioxidant and/or immune‐stimulatory activities, was studied at a glassy carbon electrode using cyclic, differential pulse, and square wave voltammetry. The oxidation of sanguinarine is a quasireversible, diffusion‐controlled process and occurred in a cascade mechanism with the formation of several oxidation products which adsorbed at the electrode surface. The oxidation of sanguinarine is pH dependent and involves the transfer of the same number of electrons and protons. The adsorbed sanguinarine oxidation products are reversibly oxidized at the glassy carbon electrode surface and their oxidation for a wide range of pHs was also studied by differential pulse and square wave voltammetry. A mechanism for the oxidation of sanguinarine at glassy carbon electrode is proposed. 相似文献
145.
Mihaela Dragusanu Brîndusa-Alina Petre Stefan Slamnoiu Camelia Vlad Tingting Tu Michael Przybylski 《Journal of the American Society for Mass Spectrometry》2010,21(10):1643-1648
We describe here an on-line combination of a surface acoustic wave (SAW) biosensor with electrospray ionization mass spectrometry
(SAW-ESI-MS) that enables the direct detection, identification, and quantification of affinity-bound ligands from a protein-ligand
complex on a biosensor chip. A trapping column was used between the SAW-biosensor and the electrospray mass spectrometer equipped
with a micro-guard column, which provides simultaneous sample concentration and desalting for the mass spectrometric analysis
of the dissociated ligand. First applications of the on-line SAW-ESI-MS combination include (1), differentiation of β-amyloid
(Aβ) epitope peptides bound to anti-Aβ antibodies; (2), the identification of immobilized Substance P peptide-calmodulin complex;
(3), identification and quantification of the interaction of 3-nitrotyrosine-modified peptides with nitrotyrosine-specific
antibodies; and (4), identification of immobilized anti-α-synuclein-human α-synuclein complex. Quantitative determinations
of protein-ligand complexes by SAW yielded dissociation constants (KD) from micro-to low nanomolar sample concentrations. The on-line bioaffinity-ESI-MS combination presented here is expected
to enable broad bioanalytical application to the simultaneous, label-free determination and quantification of biopolymer-ligand
interactions, as diverse as antigen-antibody and lectin-carbohydrate complexes. 相似文献
146.
Tingting Tu Mihaela Drăgu§anu Brînduşa-Alina Petre Don L. Rempel Michael Przybylski Michael L. Gross 《Journal of the American Society for Mass Spectrometry》2010,21(10):1660-1667
A new methodology using hydrogen/deuterium amide exchange (HDX) to determine the binding affinity of protein-peptide interactions
is reported. The method, based on our previously established approach, protein ligand interaction by mass spectrometry, titration,
and H/D exchange (PLIMSTEX) [J. Am. Chem. Soc.
2003, 125, 5252–5253], makes use of a dilution strategy (dPLIMSTEX) for HDX, using the mass of the peptide ligand as readout. We employed
dPLIMSTEX to study the interaction of calcium-saturated calmodulin with the opioid peptide β-endorphin as a model system;
the affinity results are in good agreement with those from traditional PLIMSTEX and with literature values obtained by using
other methods. We show that the dPLIMSTEX method is feasible to quantify an antigen-antibody interaction involving a 3-nitrotyrosine
modified peptide in complex with a monoclonal anti-nitrotyrosine antibody. A dissociation constant in the low nanomolar range
was determined, and a binding stoichiometry of antibody/peptide of 1:2 was confirmed. In addition, we determined that the
epitope in the binding interface contains a minimum of five amino acids. The dPLIMSTEX approach is a sensitive and powerful
tool for the quantitative determination of peptide affinities with antibodies, complementary to conventional immuno-analytical
techniques. 相似文献
147.
148.
Mihaela Badea Rodica Olar Dana Marinescu Veronica Lazar Carmen Chifiriuc Gina Vasile 《Journal of Thermal Analysis and Calorimetry》2009,97(2):781-785
This paper reports the investigation on the thermal stability of new complexes with mixed ligands of the type [Cd(NN)(C3H3O2)2(H2O)m]·nH2O [(1) NN: 1,10-phenantroline, m = 1, n = 0; (2) NN: 2,2′-bipyridine, m = 0, n = 1.5 and (C3H3O2): acrylate anion]. The IR data indicate a bidentate coordination mode for both heterocyclic amine and acrylate. The in vitro
qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity
against planktonic as well as biofilm embedded Gram-negative (Escherichia coli, Klebsiella sp., Proteus sp., Salmonella sp., Shigella sp., Acinetobacter boumani, Pseudomonas aeruginosa), Gram-positive (Bacillus subtilis, Staphylococcus aureus) and fungal (Candida albicans) strains, reference and isolated ones from the hospital environment. The thermal behaviour steps were investigated
in synthetic air flow. The thermal transformations are complex processes according to TG and DTA curves including dehydration,
amine as well as acrylate thermolysis. The final products of decomposition are the most stable metal oxides. 相似文献
149.
Kinga Zr Roberto Ortiz Ebru Saatci Ronald Bardsley Tim Parr Elisabeth Csregi Mihaela Nistor 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,76(1-2):93
An immunological capacitive biosensor for calpastatin was developed, optimized and applied for the analysis of meat extract samples. Anti-calpastatin antibody was immobilized on a gold electrode modified with a self-assembled monolayer of mercaptoundecanoic acid and Protein A from Staphylococcus aureus, and the obtained immunosensor was inserted as the working electrode in an electrochemical cell of a flow injection system. The dynamic range of the sensor was 20 to 160 ng/mL calpastatin. The electrode could be regenerated and re-used for more than 7 days with minimal reduction in sensitivity. For the analysis of real samples, the target analyte was extracted from the Longissimus dorsi muscle from beef carcasses directly after slaughtering. The extract was analyzed both with the developed immunosensor and microtiter plate ELISA, and a good correlation was obtained. However the immunosensor offers advantages of speed, simplicity, sensitivity and possibility for miniaturization over conventional assays for calpastatin quantification. 相似文献
150.
Sacarescu L Ardeleanu R Sacarescu G Simionescu M Hurduc N 《Chemical communications (Cambridge, England)》2006,(7):788-789
This work presents the synthesis and particularities of the reversible trans-cis UV light induced photoisomerization process of a polydiphenylsilane bearing (propyl-oxyphenylazo)dibenzo-18-crown-6 side groups. 相似文献