476 research outputs found

    Bulk mineralogical characterisation of oilfield reservoir rocks and sandstones using DRIFTS and partial least squares analysis

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    The feasibility of applying Partial Least Squares (PLS) to the Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) spectra of mineral mixtures, quarry sandstones and oilfield reservoir rocks has been investigated and shown considerable potential for accurate and precise mineralogical analysis. Rapid spectrum acquisition and data processing together with small sample size requirements are key advantages of the PLS–DRIFTS method. A PLS model was created from the DRIFTS spectra of mixtures of seven mineral standards chosen to represent the most frequently encountered minerals in sandstone-type rocks; quartz, dolomite, montmorillonite, illite, kaolinite, chlorite and albite. The PLS–DRIFTS model was able to quantify the mineral components of independent mixtures with an absolute error of 1 wt.% for all the minerals (concentration range 0–30 wt.%) with the exception of quartz which exhibited an absolute error of 3 wt.% (concentration range 50–90 wt.%). The results provided by applying this PLS–DRIFTS model to several sandstone-type quarry rocks and a suite of oilfield reservoir rocks were considerably better than anticipated even though the model did not describe all the mineral components present in the samples nor the entire variance of constituent mineral components (e.g. crystallinity). The model was not able to differentiate between montmorillonite and illite probably due to the similarity of the DRIFTS spectra of these minerals, but it was able to quantify the combined (montmorillonite + illite) concentrations to within 1 wt.%. The model over-predicted the concentration of albite in the quarry rocks due to the presence of K-feldspar, which has a similar DRIFTS spectrum and was not included in the model. However, the model accurately predicted the total (albite and K-feldspar) concentration to within 4 wt.%. A separate PLS–DRIFTS model constructed using the DRIFTS spectra of the oilfield reservoir rocks showed that the carbonate components, calcite and dolomite could be differentiated and quantified to within 5.0 and 3.6 wt.%, respectively. This feasibility study confirmed the strong potential of combining DRIFTS with a multivariate statistical approach such as PLS and it is clear that more sophisticated models, that incorporates and describes a higher percentage of the variance in unknowns, would further improve the predictions

    Lord of the Bridges

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    To design and build a device that automates the registration and tests for the Alief Popsicle Bridge competition and organize the data in a way that outputs the tested attributes for each bridge and assigns ranks in a specified format

    Associations between childhood maltreatment and inflammatory markers.

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    BACKGROUND:Childhood maltreatment is one of the strongest predictors of adulthood depression and alterations to circulating levels of inflammatory markers is one putative mechanism mediating risk or resilience.AimsTo determine the effects of childhood maltreatment on circulating levels of 41 inflammatory markers in healthy individuals and those with a major depressive disorder (MDD) diagnosis. METHOD:We investigated the association of childhood maltreatment with levels of 41 inflammatory markers in two groups, 164 patients with MDD and 301 controls, using multiplex electrochemiluminescence methods applied to blood serum. RESULTS:Childhood maltreatment was not associated with altered inflammatory markers in either group after multiple testing correction. Body mass index (BMI) exerted strong effects on interleukin-6 and C-reactive protein levels in those with MDD. CONCLUSIONS:Childhood maltreatment did not exert effects on inflammatory marker levels in either the participants with MDD or the control group in our study. Our results instead highlight the more pertinent influence of BMI.Declaration of interestD.A.C. and H.W. work for Eli Lilly Inc. R.N. has received speaker fees from Sunovion, Jansen and Lundbeck. G.B. has received consultancy fees and funding from Eli Lilly. R.H.M.-W. has received consultancy fees or has a financial relationship with AstraZeneca, Bristol-Myers Squibb, Cyberonics, Eli Lilly, Ferrer, Janssen-Cilag, Lundbeck, MyTomorrows, Otsuka, Pfizer, Pulse, Roche, Servier, SPIMACO and Sunovian. I.M.A. has received consultancy fees or has a financial relationship with Alkermes, Lundbeck, Lundbeck/Otsuka, and Servier. S.W. has sat on an advisory board for Sunovion, Allergan and has received speaker fees from Astra Zeneca. A.H.Y. has received honoraria for speaking from Astra Zeneca, Lundbeck, Eli Lilly, Sunovion; honoraria for consulting from Allergan, Livanova and Lundbeck, Sunovion, Janssen; and research grant support from Janssen. A.J.C. has received honoraria for speaking from Astra Zeneca, honoraria for consulting with Allergan, Livanova and Lundbeck and research grant support from Lundbeck

    Academic, clinical and personal experiences of undergraduate healthcare students during the COVID-19 pandemic: A prospective cohort study

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    BackgroundCoronavirus disease 2019 has impacted upon the role and safety of healthcare workers, with the potential to have a lasting effect on their wellbeing. Limited research has been conducted during previous pandemics exploring how student healthcare workers are impacted as they study and train for their professional careers.ObjectiveThe aim of the current study was to examine the specific impact of COVID-19 on the academic, clinical and personal experiences of healthcare students.MethodUndergraduate students across three year groups within the School of Health Sciences at Ulster University completed online Qualtrics surveys at three timepoints during one academic year (2020/2021). Quantitative survey data was downloaded from Qualtrics into SPSS Version 25 for descriptive analysis of each cross-sectional sample. Qualitative survey data was downloaded into text format, which was thematically analysed using content analysis.Results412 students completed the survey at Time 1 (October 2020), n = 309 at Time 2 (December 2020) and n = 259 at Time 3 (April 2021). Academically, the pandemic had mostly a negative impact on the learning environment, the development of practical skills, the assessment process and opportunities for peer learning and support. Students reported increased stress and challenges managing their workload and maintaining a sense of motivation and routine. Clinically, they felt unprepared by the university for placement where the pandemic had an increasingly negative impact over time on learning and skill development. In terms of personal experiences, despite the majority of students taking steps to keep physically and mentally well, negative impacts on friendships, mental wellbeing and concerns for family were reported. The pandemic had not impacted upon career choice for most students.ConclusionConsideration must be given to the development of practical skills so students feel prepared for their professional careers given the practical nature of their roles. Programme coordinators should adopt a holistic approach to student wellbein

    Psychosocial Risk Factors in Disordered Gambling: A Descriptive Systematic Overview of Vulnerable Populations

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    Background: Gambling is a behaviour engaged in by millions of people worldwide; for some, gambling can become a severely maladaptive behaviour, and previous research has identified a wide range of psychosocial risk factors that can be considered important for the development and maintenance of disordered gambling. Although risk factors have been identified, the homogeneity of risk factors across specific groups thought to be vulnerable to disordered gambling is to date, unexplored. Methods: To address this, the current review sought to conduct a systematic overview of literature relating to seven vulnerable groups: young people and adolescents, older adults, women, veterans, indigenous peoples, prisoners, and low socio-economic/income groups. Results: Multiple risk factors associated with disordered gambling were identified; some appeared consistently across most groups, including being male, co-morbid mental and physical health conditions, substance use disorders, accessibility and availability of gambling, form and mode of gambling, and experience of trauma. Further risk factors were identified that were specific to each vulnerable group. Conclusion: Within the general population, certain groups are more vulnerable to disordered gambling. Although some risk factors are consistent across groups, some risk factors appear to be group specific. It is clear that there is no homogenous pathway in to disordered gambling, and that social, developmental, environmental and demographic characteristics can all interact to influence an individual’s relationship with gambling

    Remdesivir-ivermectin combination displays synergistic interaction with improved in vitro activity against SARS-CoV-2

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    A key element for the prevention and management of COVID-19 is the development of effective therapeutics. Drug combination strategies of repurposed drugs offer several advantages over monotherapies, including the potential to achieve greater efficacy, the potential to increase the therapeutic index of drugs and the potential to reduce the emergence of drug resistance. Here, we report on the in vitro synergistic interaction between two FDA approved drugs, remdesivir and ivermectin resulting in enhanced antiviral activity against SARS-CoV-2. Whilst the in vitro synergistic activity reported here does not support the clinical application of this combination treatment strategy, due to insufficient exposure of ivermectin in vivo, the data do warrant further investigation. Efforts to define the mechanisms underpinning the observed synergistic action, could lead to the development of novel therapeutic treatment strategies
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