High-throughput screening of argan oil composition and authenticity using benchtop 1H NMR

We use 60-MHz benchtop nuclear magnetic resonance (NMR) to acquire(1)H spectra from argan oils of assured origin. We show that the low-field NMR spectrum of neat oil contains sufficient information to make estimates of compositional parameters and to inform on the presence of minor compounds. A screening method for quality and authenticity is presented based on nearest-neighbour outlier detection. A variety of oil types are used to challenge the method. In a survey of retail-purchased oils, several instances of fraud were found

Mitigating instrument effects in 60 MHz 1H NMR spectroscopy for authenticity screening of edible oils

Low field (60 MHz) 1H NMR spectroscopy was used to analyse a large (n = 410) collection of edible oils, including olive and argan, in an authenticity screening scenario. Experimental work was carried out on multiple spectrometers at two different laboratories, aiming to explore multivariate model stability and transfer between instruments. Three modelling methods were employed: Partial Least Squares Discriminant Analysis, Random Forests, and a One Class Classification approach. Clear inter-instrument differences were observed between replicated data collections, sufficient to compromise effective transfer of models based on raw data between instruments. As mitigations to this issue, various data pre-treatments were investigated: Piecewise Direct Standardisation, Standard Normal Variates, and Rank Transformation. Datasets comprised both phase corrected and magnitude spectra, and it was found that that the latter spectral form may offer some advantages in the context of pattern recognition and classification modelling, particularly when used in combination with the Rank Transformation pre-treatment

Utilisation of the static Evans method to measure magnetic susceptibilities of transition metal acetylacetonate complexes as part of an undergraduate inorganic laboratory class

The Evans method is routinely utilised to collect paramagnetic susceptibility data via the employment of relevant Nuclear Magnetic Resonance (NMR) methods. As the sample is normally spun, the lack of such a function on benchtop NMR instrumentation required a “static” approach to be employed. We have utilised the static Evan’s method approach to measure the magnetic susceptibilities, and subsequently the effective magnetic moment, of a series of synthesised transition metal acetylacetonate complexes in order to appraise the d-electron configuration. The obtained values were compared to those obtained using a Guoy balance and theoretical calculations. The collection of T1 relaxation data further exemplifies the effect of the paramagnetic centre in terms of aiding relaxation, and therefore links to Magnetic Resonance Imaging (MRI) contrast agents, thus providing students with real-world perspective of the experiment conducted

Rapid Identification of Novel Psychoactive and Other Controlled Substances Using Low-Field 1H NMR Spectroscopy

An automated approach to the collection of 1H NMR (nuclear magnetic resonance) spectra using a benchtop NMR spectrometer and the subsequent analysis, processing, and elucidation of components present in seized drug samples are reported. An algorithm is developed to compare spectral data to a reference library of over 300 1H NMR spectra, ranking matches by a correlation-based score. A threshold for identification was set at 0.838, below which identification of the component present was deemed unreliable. Using this system, 432 samples were surveyed and validated against contemporaneously acquired GC–MS (gas chromatography–mass spectrometry) data. Following removal of samples which possessed no peaks in the GC–MS trace or in both the 1H NMR spectrum and GC–MS trace, the remaining 416 samples matched in 93% of cases. Thirteen of these samples were binary mixtures. A partial match (one component not identified) was obtained for 6% of samples surveyed whilst only 1% of samples did not match at all

PANC Study (Pancreatitis: A National Cohort Study): national cohort study examining the first 30 days from presentation of acute pancreatitis in the UK

Abstract Background Acute pancreatitis is a common, yet complex, emergency surgical presentation. Multiple guidelines exist and management can vary significantly. The aim of this first UK, multicentre, prospective cohort study was to assess the variation in management of acute pancreatitis to guide resource planning and optimize treatment. Methods All patients aged greater than or equal to 18 years presenting with acute pancreatitis, as per the Atlanta criteria, from March to April 2021 were eligible for inclusion and followed up for 30 days. Anonymized data were uploaded to a secure electronic database in line with local governance approvals. Results A total of 113 hospitals contributed data on 2580 patients, with an equal sex distribution and a mean age of 57 years. The aetiology was gallstones in 50.6 per cent, with idiopathic the next most common (22.4 per cent). In addition to the 7.6 per cent with a diagnosis of chronic pancreatitis, 20.1 per cent of patients had a previous episode of acute pancreatitis. One in 20 patients were classed as having severe pancreatitis, as per the Atlanta criteria. The overall mortality rate was 2.3 per cent at 30 days, but rose to one in three in the severe group. Predictors of death included male sex, increased age, and frailty; previous acute pancreatitis and gallstones as aetiologies were protective. Smoking status and body mass index did not affect death. Conclusion Most patients presenting with acute pancreatitis have a mild, self-limiting disease. Rates of patients with idiopathic pancreatitis are high. Recurrent attacks of pancreatitis are common, but are likely to have reduced risk of death on subsequent admissions. </jats:sec

Detection, discrimination and quantification of amphetamine, cathinone and nor-ephedrine regioisomers using benchtop 1H and 19F nuclear magnetic resonance spectroscopy

Amphetamine and cathinone derivatives are abused recreationally due to the sense of euphoria they provide to the user. Methodologies for the rapid detection of the drug derivative present in a seized sample, or an indication of the drug class, are beneficial to law enforcement and healthcare providers. Identifying the drug class is prudent because derivatisation of these drugs, to produce regioisomers, for example, occurs frequently to circumvent global and local drug laws. Thus, newly encountered derivatives might not be present in a spectral library. Employment of benchtop nuclear magnetic resonance (NMR) could be used to provide rapid analysis of seized samples as well as identifying the class of drug present. Discrimination of individual amphetamine-, methcathinone-, N-ethylcathinone and nor-ephedrine-derived fluorinated and methylated regioisomers is achieved herein using qualitative automated 1H NMR analysis and compared to gas chromatography–mass spectrometry (GC–MS) data. Two seized drug samples, SS1 and SS2, were identified to contain 4-fluoroamphetamine by 1H NMR (match score median = 0.9933) and GC–MS (RRt = 5.42–5.43 min). The amount of 4-fluoroamphetamine present was 42.8%–43.4% w/w and 48.7%–49.2% w/w for SS1 and SS2, respectively, from quantitative 19F NMR analysis, which is in agreement with the amount determined by GC–MS (39.9%–41.4% w/w and 49.0%–49.3% w/w). The total time for the qualitative 1H NMR and quantitative 19F NMR analysis is ~10 min. This contrasts to ~40 min for the GC–MS method. The NMR method also benefits from minimal sample preparation. Thus, benchtop NMR affords rapid, and discriminatory, analysis of the drug present in a seized sample

Detection, discrimination and quantification of amphetamine, cathinone and nor-ephedrine regioisomers using benchtop 1H and 19F NMR spectroscopy.

Amphetamine and cathinone derivatives are abused recreationally due to the sense of euphoria they provide to the user. Methodologies for the rapid detection of the drug derivative present in a seized sample, or an indication of the drug class, is beneficial to law-enforcement and healthcare providers. Identifying the drug class is prudent because derivatisation of these drugs, to produce regioisomers for example, occurs frequently to circumvent global and local drug laws. Thus, newly encountered derivatives might not be present in a spectral library. Employment of benchtop NMR could be used to provide rapid analysis of seized samples as well as identifying the class of drug present. Discrimination of individual amphetamine-, methcathinone-, N-ethylcathinone and nor-ephedrine-derived fluorinated and methylated regioisomers is achieved herein using qualitative automated 1H NMR analysis and compared to GC-MS data. Two seized drug samples, SS1 and SS2, were identified to contain 4-fluoroamphetamine by 1H NMR (match score median = 0.9933) and GC-MS (RRt = 5.42-5.43 min). The amount of 4-fluoroamphetamine present was 42.8 - 43.4% w/w and 48.7 - 49.2% w/w for SS1 and SS2 respectively from quantitative 19F NMR analysis, which is in agreement with the amount determined by GC-MS (39.9 - 41.4% w/w and 49.0 - 49.3% w/w). The total time for the qualitative 1H NMR and quantitative 19F NMR analysis is ca. 10 min. This contrasts to ca. 40 min for the GC-MS method. The NMR method also benefits from minimal sample preparation. Thus, benchtop NMR affords rapid, and discriminatory, analysis of the drug present in a seized sample

Performance management in construction : a conceptual framework.

This paper presents a review of the literature on performance management and measurement in various industries with the aim of transferring best practice into construction. A framework is presented which ensures that effective strategies are deployed to form the performance management system that construction organizations can adopt. The performance measurement process (conceptual) framework (PMPF) adopts the balanced scorecard (BSC) with the addition of a number of elements and perspectives. It rationalizes the relationships between performance measures and goals derived from strategy, so the impact of those measures on an organization's performance can be examined and analysed to indicate potential areas for improvemen

The Impact of Chronic Cough:A Cross-Sectional European Survey

PURPOSE: Studies that investigate the impact of chronic cough have largely focused on patients attending secondary care. Our aim was to investigate the opinions of the wider general population across Europe. METHODS: An internet survey was made available in 12 languages on the European Lung Foundation website, between January 2012 and April 2013. RESULTS: Of 1120 respondents from 29 different European countries, 67 % were female, mean age 51 years (SD 15), median cough duration 2-5 years. The majority of respondents reported cough impacted their quality of life, mood and ability to undertake activities. Despite 72 % of respondents having visited their doctor ≥3 times, only 53 % had received a diagnosis. Asthma was the most common diagnosis (23 %). Most respondents reported limited or no effectiveness of medications. 88 % of respondents reported that they would like more information to be available on chronic cough. CONCLUSIONS: Chronic cough has a negative impact on quality of life. Further work is needed to raise awareness, promote management strategies, develop effective treatments and consider the educational and support needs of patients with chronic cough