Implementation of the multireference Brillouin-Wigner and Mukherjee's coupled cluster methods with non-iterative triple excitations utilizing reference-level parallelism

In this paper we discuss the performance of the non-iterative state-specific multireference coupled cluster (SS-MRCC) methods accounting for the effect of triply excited cluster amplitudes. The corrections to the Brillouin-Wigner and Mukherjee's MRCC models based on the manifold of singly and doubly excited cluster amplitudes (BW-MRCCSD and Mk-MRCCSD, respectively) are tested and compared with exact full configuration interaction results for small systems (H(2)O, N(2), and Be(3)). For the larger systems (naphthyne isomers) the BW-MRCC and Mk-MRCC methods with iterative singles, doubles, and non-iterative triples (BW-MRCCSD(T) and Mk-MRCCSD(T)) are compared against the results obtained with single reference coupled cluster methods. We also report on the parallel performance of the non-iterative implementations based on the use of processor groups.     

Preparation and Evaluation of [18F]AlF-NOTA-NOC for PET Imaging of Neuroendocrine Tumors: Comparison to [68Ga]Ga-DOTA/NOTA-NOC

Background: The somatostatin receptors 1–5 are overexpressed on neuroendocrine neoplasms and, as such, represent a favorable target for molecular imaging. This study investigates the potential of [¹⁸F]AlF-NOTA-[1-Nal³]-Octreotide and compares it in vivo to DOTA- and NOTA-[1-Nal³]-Octreotide radiolabeled with gallium-68. Methods: DOTA- and NOTA-NOC were radiolabeled with gallium-68 and NOTA-NOC with [¹⁸F]AlF. Biodistributions of the three radioligands were evaluated in AR42J xenografted mice at 1 h p.i and for [¹⁸F]AlF at 3 h p.i. Preclinical PET/CT was applied to confirm the general uptake pattern. Results: Gallium-68 was incorporated into DOTA- and NOTA-NOC in yields and radiochemical purities greater than 96.5%. NOTA-NOC was radiolabeled with [¹⁸F]AlF in yields of 38 ± 8% and radiochemical purity above 99% after purification. The biodistribution in tumor-bearing mice showed a high uptake in tumors of 26.4 ± 10.8 %ID/g for [⁶⁸Ga]Ga-DOTA-NOC and 25.7 ± 5.8 %ID/g for [⁶⁸Ga]Ga-NOTA-NOC. Additionally, [¹⁸F]AlF-NOTA-NOC exhibited a tumor uptake of 37.3 ± 10.5 %ID/g for [¹⁸F]AlF-NOTA-NOC, which further increased to 42.1 ± 5.3 %ID/g at 3 h p.i. Conclusions: The high tumor uptake of all radioligands was observed. However, [¹⁸F]AlF-NOTA-NOC surpassed the other clinically well-established radiotracers in vivo, especially at 3 h p.i. The tumor-to-blood and -liver ratios increased significantly over three hours for [¹⁸F]AlF-NOTA-NOC, making it possible to detect liver metastases. Therefore, [¹⁸F]AlF demonstrates promise as a surrogate pseudo-radiometal to gallium-68.     

On the theoretical problems in constructing interactions involving higher-spin massless particles

It is shown that a gauge theory of self-interacting massless spin-3 particles which is analogous to Yang-Mills or the theory of gravity does not exist. A way out may be the existence of an interacting infinite family of massless particles of various spins. The first-order interactions which are possible between such particles show a remarkable structure. This is established by explicit construction. Detailed results are obtained for the possible algebraic structures which one may obtain for gauge theories which are induced from the gauge invariance of free lagrangians.     

Bose-Einstein correlations in neutrino and antineutrino interactions in deuterium

Bose-Einstein correlations between pions of equal charge have been observed in Charged Current and Neutral Current (anti)neutrino-deuterium interactions in the BEBC bubble chamber exposed to the SPS wide band beam. The pion emission region is found to be essentially spherical with a mean radius of (0.48±0.07) fm; the chaoticity parameter is 0.36±0.04.     

Mathematical programming in the Netherlands

Results of an exhaustive survey of mathematical programming in the Netherlands held in 1982 are presented and, where applicable, compared to a survey held in 1976. It appears that the growth rate has levelled off, that about half of the largest one hundred industrial firms in the Netherlands now apply MP and that the users are quite satisfied with LP programs except for input, output and documentation.     

Characterization of an ethylene free jet

The rotational population distribution in a free molecular jet of ethylene, C₂H₄, is found to be thermal over a range of distances below the nozzle (z/d=0.5–13.2, nozzle diameter d=0.50 mm). Results for on-axis rotational temperature, number density and flow velocity are presented. The average number of gas-kinetic collisions experienced by any molecule in travelling some distance along the jet axis is calculated.     

Attenuation corrections for in-cylinder NO LIF measurements in a heavy-duty Diesel engine

Quantification of the nitric oxide (NO) concentration inside the cylinder of a Diesel engine by means of laser-induced fluorescence (LIF) measurements requires, amongst others, knowledge of the attenuation of the ultraviolet radiation involved. We present a number of laser diagnostic techniques to assess this attenuation, enabling a correction for laser intensity and detection efficiency of the raw NO LIF data. Methods discussed include overall laser beam transmission, bidirectional laser scattering (bidirectional LIF), spectrally resolved fluorescence imaging, and Raman scattering by N₂. A combination of techniques is necessary to obtain the complete attenuation of laser beam and NO fluorescence. The overall laser beam transmission measurements and bidirectional LIF measurements (the latter yielding spatially resolved transmission) provide evidence of a non-uniform attenuation distribution, with predominant attenuation within or near the piston bowl. Fluorescence imaging of multiple vibrational bands through a spectrograph is shown to be a powerful method for obtaining spatially resolved data on the transmission losses of fluorescence. Special attention is paid to the role of CO₂ and O₂ as UV light absorbers, and the consequences to different excitation-detection schemes for NO. PACS 82.33.Vx; 42.62.Fi; 33.20.t     

Analysis of glycolytic intermediates in Saccharomyces cerevisiae using anion exchange chromatography and electrospray ionization with tandem mass spectrometric detection

The purpose of this study is to selectively and quantitatively analyze several glycolytic intermediates in cells of Saccharomyces cerevisiae using high-performance anion exchange chromatography (HPAEC) coupled to electrospray ionization tandem mass spectrometry for the analysis. A sodium hydroxide gradient is used to separate the glycolytic compounds and after the column sodium hydroxide is reduced by proton exchange with a membrane device prior to introduction to the mass spectrometer. The detection limits for 10 μl samples are down to the 0.4–5 pmol range. This corresponds for the intracellular metabolites to a range of 2–20 nmol per gram biomass dry weight (DW). Standard addition did reveal some influence of the sample matrix on the measured concentrations. Separation and analysis is hardly affected by the high sulfate and phosphate concentrations (1 mM) in the fermentation medium and by the intracellular matrix. Validation of the glucose-6-phosphosphate LC–MS–MS analysis results with enzymatic analysis showed an excellent agreement between the two methods. The suitability of the method was clearly shown by analyzing a series of steady state S. cerevisiae samples from a carbon limited aerobic chemostat culture.     

High-yield formation of giant bis(bicyclic) and crypt-tris(bicyclic) molecules under normal reaction conditions

We report the unexpected result of the reaction of 1, 3-bis[(9-anthrylmethoxy)methyl]benzene (1a) or 1,3, 5-tris[(9-anthrylmethoxy)methyl]benzene (1b) with tris(2-maleimidoethyl)amine (2) in homogeneous solution leading to giant bis(bicyclic) and crypt-tris(bicyclic) molecules. The anticipated, intractable solids are obtained in a condensed state reaction using an oscillating mill.