Publications by authors named "Andrew Parrott"

Application of multivariate curve resolution to non-invasive Raman spectra has been investigated for rapid on-line analysis of crystallisation processes and high-throughput screening. Exploring quantification of mefenamic acid solid forms (form I, form II, and dimethylformamide solvate) from the Raman spectra indicated excellent agreement with off-line X-ray analysis.

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A detailed investigation into the mechanistic course of -hydroxyphthalimide catalyzed oxidation of benzylic centers using sodium chlorite as the stoichiometric oxidant is reported. Through a combination of experimental, spectroscopic, and computational techniques, the transformation is interrogated, providing improved reaction conditions and an enhanced understanding of the mechanism. Performing the transformation in the presence of acetic acid or a pH 4.

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The applicability of Raman spectroscopy for phase discrimination of metal-organic frameworks (MOFs) has been demonstrated with F4_MIL-140A(Ce) and F4_UiO-66(Ce); analogues prepared from the same metal and ligand sources. Each analogue exhibits unique Raman peaks, with significant differences in the low frequency region, which is more sensitive to structural variations. Non-invasive Raman monitoring of F4_MIL-140A(Ce) synthesis indicated evolution of a unique MOF Raman peak with reaction progress; conversion of this Raman signal to extent of crystallisation was in good agreement with reported reaction kinetics determined a synchrotron diffraction method.

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Changes in temperature can significantly affect spectroscopic-based methods for in situ monitoring of processes. As varying temperature is inherent to many processes, associated temperature effects on spectra are unavoidable, which can hinder solute concentration determination. Ultraviolet (UV) and mid-infrared (IR) data were acquired for l-ascorbic acid (LAA) in MeCN/HO (80:20 w/w) at different concentrations and temperatures.

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Process applications of mid-infrared (MIR) spectrometry may involve replacement of the spectrometer and/or measurement probe, which generally requires a calibration transfer method to maintain the accuracy of analysis. In this study, direct standardisation (DS), piecewise direct standardisation (PDS) and spectral space transformation (SST) were compared for analysis of ternary mixtures of acetone, ethanol and ethyl acetate. Three calibration transfer examples were considered: changing the spectrometer, multiplexing two probes to a spectrometer, and changing the diameter of the attenuated total reflectance (ATR) probe (as might be required when scaling up from lab to process analysis).

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Context: The detection of low-level persistent or relapsed B-cell neoplasms, particularly post-therapy, can be challenging, often requiring multiple testing modalities.

Objective: Here we investigate the utility of CD19-based selection of neoplastic B-cells (CD19S) as an enrichment strategy to improve the detection rate of cytogenetic abnormalities in post-therapy samples of B-cell neoplasms, especially those with low-level disease.

Design: In a cohort largely comprised of post-therapy B-ALL and CLL samples, we performed fluorescence in situ hybridization (FISH) analysis on CD19-selected cells (CD19S FISH) in 128 specimens from 88 patients, and on non-selected cells (NS FISH) in a subset of cases.

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Biobased epoxy thermoset polymers were prepared from lignin hydrogenolysis oils produced from native hardwood lignin. Native lignin in and wood was reacted in situ under Pd-catalyzed mild hydrogenolysis conditions to give depolymerized lignin oils in yields up to 98 wt %. Reacting these lignin oils with epichlorohydrin produced biobased epoxy resins.

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Mantle cell lymphomas (MCLs) are the prototypic B-cell non-Hodgkin lymphomas defined by cyclin D1 gene (CCND1; or other cyclin D family gene) rearrangements. However, extremely rare cases of diffuse large B-cell lymphomas (DLBCLs) harboring CCND1 rearrangements, resulting in cyclin D1 protein expression, have also been reported. In this report, we describe an unusual primary large B-cell lymphoma of non-germinal center immunophenotype of the central nervous system (CNS) in an elderly male patient, which was negative for CD5 and SOX11, and exhibited cyclin D1 expression.

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Mephedrone and MDMA are both constituents of party drugs, with mephedrone being relatively new compared to MDMA. This review compares current knowledge regarding the patterns of usage and neuropsychobiological effects of both mephedrone and MDMA. Both drugs share common psychoactive effects, the duration of which is significantly shorter with mephedrone use, attributing towards a pattern of binge use among users.

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MDMA (3,4-methylendioxymethamphetamine), also known as Ecstasy, is a stimulant drug recreationally used by young adults usually in dance clubs and raves. Acute MDMA administration increases serotonin, dopamine and noradrenaline by reversing the action of the monoamine transporters. In this work, we review the studies carried out over the last 30 years on the neuropsychobiological effects of MDMA in humans and mice and summarise the current knowledge.

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The conversion of [IrCl(COD)(IMes)] (COD = cis, cis-1,5-cyclooctadiene, IMes = 1,3-bis(2,4,6-trimethyl-phenyl)imidazole-2-ylidene) in the presence of an excess of para-hydrogen ( p-H) and a substrate (4-aminopyridine (4-AP) or 4-methylpyridine (4-MP)) into [Ir(H)(IMes)(substrate)]Cl is monitored by H NMR spectroscopy using a benchtop (1 T) spectrometer in conjunction with the p-H-based hyperpolarization technique signal amplification by reversible exchange (SABRE). A series of single-shot H NMR measurements are used to monitor the chemical changes that take place in solution through the lifetime of the hyperpolarized response. Non-hyperpolarized high-field H NMR control measurements were also undertaken to confirm that the observed time-dependent changes relate directly to the underlying chemical evolution.

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para-Hydrogen (p-H) induced polarisation (PHIP) is an increasingly popular method for sensitivity enhancement in NMR spectroscopy. Its growing popularity is due in part to the introduction of the signal amplification by reversible exchange (SABRE) method that generates renewable hyperpolarisation in target analytes in seconds. A key benefit of PHIP and SABRE is that p-H can be relatively easily and cheaply produced, with costs increasing with the desired level of p-H purity.

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Background: An attentional bias towards substance-related stimuli has been demonstrated with alcohol drinkers and many other types of substance user. There is evidence to suggest that the strength of an attentional bias may vary as a result of context (or use intention), especially within Ecstasy/MDMA users.

Objective: Our aim was to empirically investigate attentional biases by observing the affect that use intention plays in recreational MDMA users and compare the findings with that of alcohol users.

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Raman spectroscopy has been used to provide a rapid, noninvasive, and nondestructive quantification method for determining the parahydrogen fraction of hydrogen gas. The basis of the method is the measurement of the ratio of the first two rotational bands of hydrogen at 355 cm and 586 cm corresponding to parahydrogen and orthohydrogen, respectively. The method has been used to determine the parahydrogen content during a production process and a reaction.

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Benchtop NMR spectrometers operating with low magnetic fields of 1-2 T at sub-ppm resolution show great promise as analytical platforms that can be used outside the traditional laboratory environment for industrial process monitoring. One current limitation that reduces the uptake of benchtop NMR is associated with the detection fields' reduced sensitivity. Here we demonstrate how para-hydrogen (p-H2) based signal amplification by reversible exchange (SABRE), a simple to achieve hyperpolarization technique, enhances agent detectability within the environment of a benchtop (1 T) NMR spectrometer so that informative 1H and 13C NMR spectra can be readily recorded for low-concentration analytes.

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Many novel psychoactive substances (NPS) have entered the recreational drug scene in recent years, yet the problems they cause are similar to those found with established drugs. This article will debate the psychobiological effects of these newer and more traditional substances. It will show how they disrupt the same core psychobiological functions, so damaging well-being in similar ways.

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Signal amplification by reversible exchange (SABRE) is a hyperpolarisation technique that catalytically transfers nuclear polarisation from parahydrogen, the singlet nuclear isomer of H , to a substrate in solution. The SABRE exchange reaction is carried out in a polarisation transfer field (PTF) of tens of gauss before transfer to a stronger magnetic field for nuclear magnetic resonance (NMR) detection. In the simplest implementation, polarisation transfer is achieved by shaking the sample in the stray field of a superconducting NMR magnet.

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MDMA/Ecstasy has had a resurgence in popularity, with recent supplies comprising higher strength MDMA, potentially leading to increased drug-related harm. Neurocognitive problems have been widely reported in ecstasy users, equally some studies report null findings, and it remains unclear which factors underlie the development of neurocognitive impairments. This review covers the empirical research into brain activity during neurocognitive performance, using fMRI, fNIRS, and EEG.

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In many communities, cannabis is perceived as a low-risk drug, leading to political lobbying to decriminalise its use. Acute and chronic cannabis use has been shown to be harmful to several aspects of psychological and physical health, such as mood states, psychiatric outcomes, neurocognition, driving and general health. Furthermore, cannabis is highly addictive, and the adverse effects of withdrawal can lead to regular use.

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Aims: The purpose of this article is to debate current understandings about the psychobiological effects of recreational 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy'), and recommend theoretically-driven topics for future research.

Methods: Recent empirical findings, especially those from novel topic areas were reviewed. Potential causes for the high variance often found in group findings were also examined.

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Aims: Recreational drugs are taken for their positive mood effects, yet their regular usage damages well-being. The psychobiological mechanisms underlying these damaging effects will be debated.

Methods: The empirical literature on recreational cannabinoids and stimulant drugs is reviewed.

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The recreational use of various stimulant drugs has been implicated in the development of movement disorders through dysregulation of the dopaminergic and serotoninergic neurotransmitter systems. The present study investigated psychomotor differences in current and former recreational stimulant drug users compared with nonusing controls. Sixty participants comprised 3 groups: 20 current stimulant drug users (CSUs; 11 men, aged 31.

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Most research into 3,4-methylenedioxymethamphetamine (MDMA) has debated its psychobiological effects in relation to neurotransmission. This article debates the contributory roles of the neurohormones oxytocin and cortisol for their psychobiological effects in humans. The empirical literature on these neurohormones is reviewed and suggestions for future research outlined.

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