An exact chiral amorphous spin liquid.

Topological insulator phases of non-interacting particles have been generalized from periodic crystals to amorphous lattices, which raises the question whether topologically ordered quantum many-body phases may similarly exist in amorphous systems? Here we construct a soluble chiral amorphous quantum spin liquid by extending the Kitaev honeycomb model to random lattices with fixed coordination number three. The model retains its exact solubility but the presence of plaquettes with an odd number of sides leads to a spontaneous breaking of time reversal symmetry. We unearth a rich phase diagram displaying Abelian as well as a non-Abelian quantum spin liquid phases with a remarkably simple ground state flux pattern. Furthermore, we show that the system undergoes a finite-temperature phase transition to a conducting thermal metal state and discuss possible experimental realisations.

z+: Neutron cross section separation from wide-angle uniaxial polarization analysis.

We introduce a simple method to extract the nuclear coherent and isotope incoherent, spin incoherent, and magnetic neutron scattering cross section components from powder scattering data measured using a single neutron beam polarization direction and a position-sensitive detector with large out-of-plane coverage. The method draws inspiration from polarized small-angle neutron scattering and contrasts with conventional so-called "xyz" polarization analysis on wide-angle instruments, which requires measurements with three orthogonal polarization directions. The viability of the method is demonstrated on both simulated and experimental data for the classical "spin ice" system Ho2Ti2O7, the latter from the LET direct geometry spectrometer at the ISIS facility. The cross section components can be reproduced with good fidelity by either fitting the out-of-plane angle dependence around a Debye-Scherrer cone or grouping the data by angle and performing a matrix inversion. The limitations of the method and its practical uses are discussed.

The analysis of thebaine in urine for the detection of poppy seed consumption.

The consumption of poppy seeds in various foods may lead to a positive opiate result in urine subjected to testing for drugs of abuse. As a natural constituent of poppy seeds, thebaine was investigated as a possible marker for poppy seed consumption. Poppy seeds were examined for opiate content by gas chromatography-ion trap mass spectrometry (GC-MS) after extraction with methanol. Urine samples spiked with thebaine and urine from subjects given 11 g of poppy seeds were tested for the presence of thebaine, codeine, and morphine. Street heroin, one morphine and one codeine tablet, and urine from individuals who had used heroin were also examined for thebaine. Urine specimens were screened by enzyme immunoassay (EMIT) and confirmed for thebaine by GC-MS using a solid-phase extraction method. The GC-MS assay showed a linear response over a range of 1-100 ng/mL and a limit of detection of 0.5 ng/mL. Thebaine was detectable in the urine of poppy seed eaters in concentrations ranging from 2 to 81 ng/mL. Because thebaine was absent in powdered drugs and the urine of true opiate drug users, thebaine is proposed as a direct marker for poppy seed use.

Improved GC/MS analysis of opiates with use of oxime-TMS derivatives.

An improved gas chromatographic/mass spectrometric (GC/MS) assay is described for the quantitation of codeine and morphine as trimethylsyl (TMS) derivatives. The TMS derivatization of ketone-containing opiates results in the formation of multiple derivatives. Some of these products have retention times close to those of codeine-TMS and morphine-TMS. When the keto-opiates are present in samples assayed for codeine and morphine in urine, they can interfere with the quantitation of these commonly targeted opiates. The assay was improved with the addition of a pre-BSTFA derivatization step, whereby hydroxylamine was used to convert the keto-opiates into the corresponding oxime derivative. These derivatives were then reacted with BSTFA to form the TMS ethers and TMS oxime derivatives. The oxime step enabled production of single derivatives for hydrocodone and hydromorphone. In addition, the retention times for the oxime-TMS derivatives were increased so that they no longer elute near the targeted drugs of codeine and morphine. The addition of the oxime step does not affect the sylation of codeine and morphine, and the accuracy and precision of this assay were unaffected.