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Mineral diagenesis in a carbonate-rich mudstone: The Lower Carboniferous Hodder Shale, UK
No full textMineral authigenesis in mudstones respond differently across the compositional spectrum of fine-grained rocks resulting in a complex array of possible rock fabrics that affect the mechanical capacity of mudstones. Within carbonate-rich mudstones, geochemical controls on silicate and carbonate mineral reactions are variable and poorly understood. Here we analyse the diagenetic minerals of the carbonate-rich Hodder Mudstone from the Carboniferous Bowland Basin, UK, using SEM petrography combined with X-ray-based inorganic geochemical data. Our findings show that up to 90% of quartz cement in the samples are diagenetic in origin, originating mainly from biogenic silica dissolution, and clay mineral reactions. It is also evident that due to the varying diagenetic silica-yielding reactions, authigenic silica overgrowths and isolated authigenic quartz crystals are localised in argillaceous samples while calcareous samples are characterized by silica replacement textures and quartz/calcite intergrowths. Moreover, euhedral dolomite crystals are concentrated within argillaceous units in comparison with calcareous units which are characterised by anhedral dolomite precipitation and replacement textures. These finding presents a case for facies28 selective cementation as both early and burial diagenetic alterations were observed to be controlled by primary depositional components of biogenic debris and extrabasinal silicate detritus that resulted in complex and variable precipitation of authigenic minerals
Non-thermal plasma catalytic ammonia synthesis over Ni catalyst supported on MgO/SBA-15
No full textNon-thermal plasma (NTP) enabled ammonia synthesis is recently considered a sustainable technique as compared to the Haber–Bosch (HB) process. Herein we demonstrate the NTP catalytic ammonia synthesis in an dielectric barrier discharge (DBD) plasma reactor using mesoporous silica (SBA-15) supported Ni catalysts under ambient condition. Specifically, two types of MgO modified SBA-15 were developed (as the catalyst support) by the in situ doping and incipient wetness impregnation (IWI) methods, respectively. Experimental results demonstrated that the addition of Mg in SBA-15 via the IWI method favored the ammonia synthesis rate under NTP conditions. The developed Ni-Mg0.02/SBA-15-IWI catalyst exhibited the highest ammonia synthesis rate and energy efficiency value of 4.4 mmol h−1 gcat−1 and 1.05 gNH3 kWh−1, outperformed the Ni/SBA-15 and Ni-Mg0.02/SBA-15-In situ catalyst (i.e. the doping of Mg via in situ method). HRTEM and EDS mapping analysis showed that the addition of Mg (on SBA-15) via the IWI method favored the dispersion of Ni on the catalyst surface and the Ni-support interaction, i.e., uniform distribution of Ni nanoparticles of 5.1 ± 1.1 nm in the Ni-Mg0.02/SBA-15-IWI catalyst, which enhanced the ammonia synthesis performance. Finally, the developed Ni-Mg0.02/SBA-15-IWI catalyst displayed a slight decrease of ammonia synthesis rate from ~4.42 to ~3.89 mmol h−1 gcat−1 over a 40 h on stream, which could be attriburated to the aggregation of Ni particles based on the post-reaction HRTEM analysis.<br/
IDENTIFYING THE BEST METHODS TO REPORT ON THE POST-VACCINATION SURVEILLANCE OF PHYSICAL SIDE-EFFECTS OF THE COVID-19 VACCINES: A SYSTEMATIC REVIEW
No full textIntroduction: On the 11th of March 2020, the World Health Organisation declared COVID-19 to be a global pandemic. This had led to the development of many novel vaccines for which effective post-vaccination surveillance is essential. This study aims to synthesise post-vaccination surveillance of physical side-effects to learn the best method that can be applied to the surveillance of novel COVID-19 vaccines. Methods: A full systematic search was performed on four databases following the PRISMA guidelines. Following the inclusion and exclusion criteria, and hand-searching the eligible papers, a total of seven studies were included in this review. The risk of bias within studies and their quality was assessed using the Critical Appraisal for Public Health Checklist.Results: The seven studies included were from six countries representing both active and passive surveillance systems. The results showed reliability and reproducibility between data across countries. They also provided a good framework for how post-vaccination surveillance can be performed in low-income countries. Conclusions: The reporting of post-vaccine side-effects is essential. Active and passive systems were essential to encourage reporting of AEFIs and should be encouraged globally. A combination of active and passive surveillance should be used to monitor adverse events relating to the novel COVID-19 vaccines
Prognostic impact of bronchoalveolar lavage galactomannan and Aspergillus culture results on survival in COVID-19 ICU patients: a post-hoc analysis from the European Confederation of Medical Mycology (ECMM) COVID-19-associated pulmonary aspergillosis (CAPA) Study
No full textCritically ill patients with coronavirus disease 2019 (COVID-19) may develop COVID-19-associated pulmonary aspergillosis (CAPA), that impact their chances of survival. Whether positive bronchoalveolar lavage fluid (BALF) mycological tests can be used as a survival proxy remains unknown. We conducted a post-hoc analysis of a previous multicenter, multinational observational study with the aim of assessing the differential prognostic impact of BALF mycological tests, namely positive (≥ 1.0 optical density index) BALF galactomannan (GM) and positive BALF Aspergillus culture alone or in combination in critically ill patients with COVID-19. Of the 592 patients critically ill patients with COVID-19 enrolled in the main study, 218 were included in this post-hoc analysis as they had both test results available. CAPA was diagnosed in 56/218 patients (26%). Most cases were probable CAPA (51/56, 91%) and fewer were proven CAPA (5/56, 9%). In the final multivariable model adjusted for between-center heterogeneity, an independent association with 90-day mortality was observed for the combination of positive BALF GM and positive BALF Aspergillus culture in comparison with both tests negative (hazard ratio 2.53, 95% CI 1.28-5.02, p = 0.008). The other independent predictors of 90-day mortality were increasing age and active malignant disease. In conclusion, the combination of positive BALF GM and positive BALF Aspergillus culture was associated with increased 90-day mortality in critically ill patients with COVID-19. Additional study is needed to explore the possible prognostic value of other BALF markers.Key words: CAPA; GM; biomarker; galactomannan; Aspergillus; COVID-19; BALF.<br/
THE ROLE OF AGE IN DELAYS TO RHEUMATOLOGICAL CARE IN JUVENILE IDIOPATHIC ARTHRITIS
No full textObjective: To investigate the relationship between age and symptom duration at initial presentation to paediatric rheumatology for JIA. Methods: In children and young people (CYP) enrolled in the Childhood Arthritis Prospective Study pre-March 2018, an association between age at presentation (<5, 5-11 and >11 years) and symptom duration was tested via multivariable linear regression.Results: In 1577 CYP, 5-11 year olds took 3.2 months longer and >11 year olds 6.9 months longer to reach paediatric rheumatology than <5 year olds. Conclusion: Adolescents take longer to reach paediatric rheumatology, potentially impacting their longer-term outcomes given the window of opportunity for JIA. <br/
ADBSat: Verification and validation of a novel panel method for quick aerodynamic analysis of satellites
No full textWe present the validation of ADBSat, a novel implementation of the panel method including a fast pseudo-shading algorithm, that can quickly and accurately determine the forces and torques on satellites in free-molecular flow. Our main method of validation is comparing test cases between ADBSat, the current de facto standard of direct simulation Monte Carlo (DSMC), and published literature. ADBSat exhibits a significantly shorter runtime than DSMC and performs well, except where deep concavities are present in the satellite models. The shading algorithm also experiences problems when a large proportion of the satellite surface area is oriented parallel to the flow, but this can be mitigated by examining the body at small angles to this configuration (± 0.1◦). We recommend that an error interval on ADBSat outputs of up to 3% is adopted. Therefore, ADBSat is a suitable tool for quickly determining the aerodynamic characteristics of a wide range of satellite geometries in different environmental conditions in VLEO. It can also be used in a complementary manner to identify cases that warrant further investigation using other numerical-based methods.<br/
Self-assembled 1T-MoS2/Functionalized Graphene Composite Electrodes for Supercapacitor Devices
No full textTwo-dimensional (2D) materials such as graphene and molybdenum disulfide (MoS2) have been investigated widely for applications in energy storage, including supercapacitors, due to their high specific surface area, potential redox activity and mechanical flexibility. However, electrodes comprised of either pure graphene and MoS2 have failed to reach their potential due to restacking of the layered structure and poor electrical conductivity. It has been shown previously that composite electrodes made from a mixture of graphene and MoS2 partially counteract these issues, however performance is still limited by poor mixing at the nanoscale. Herein, we form a true composite electrode by chemically functionalizing the graphene so that the negatively charged surface can self-assemble with the positively charged 1T-MoS2 to give an alternating layer structure. These alternately restacked 2D materials were then used to produce supercapacitor electrodes, and their energy storage properties characterized. This stacked structure has increased the interlayer spacing of 1T-MoS2 which was indicated by the increase of the intensity of the (001) peak in the XRD spectra. Furthermore, the typically metastable 1T-MoS2 was stabilized by the interaction with the functionalized graphene, preventing it reverting back to the 2H phase, which was observed when pristine graphene was used. The graphene was functionalized using either 4-bromobenzenediazonium (BBD) or 4-nitrobenzenediazonium (NBD), with the later giving optimal capacitance when mixed with the MoS2. The alternative layer graphene-MoS2 structure was confirmed by Raman spectroscopy and electron microscopy and lead to high specific capacitance (290 F cm-3 at 0.5 A g-1) and 90 % retention of capacitance after 10,000 cycles
Childcare Support under Social Security in the UK: Is it Working?
No full textBy facilitating engagement in the labour force and thus potentially contributing to the amelioration of individual poverty, the availability of affordable childcare is an issue of both economic and social significance and is recognised as such across Europe. Since a large majority of the parents who assume caring responsibilities for young children, particularly lone parents, are women, childcare support is also seen as an equality issue in relation to employment. Children’s interest in the parents’ childcare support is also recognised under the UN Convention on the Rights of the Child. Support towards the cost of childcare has been an important feature of the UK social security system since the 1980s and is currently located within Universal Credit (UC) and Working Tax Credit (WTC) legislation. UC and WTC support sits alongside other childcare support schemes, including Tax-free Childcare. For the most disadvantaged, it is however the social security system’s role in this field that has the greatest importance, not least because the imposition of work conditionality and particularly its extension to lone parents with young children is premised on the claimant’s ability to access childcare arrangements. This article evaluates the framework for supporting childcare costs within the social security system in the light of the evidence to date on its operation, including the inherent discrimination that prompted the recent judicial review challenge in Salvato. It highlights flaws in the system and among other things calls for increased monitoring and public scrutiny of its operation
EULAR points to consider when analysing and reporting comparative effectiveness research using observational data in rheumatology
No full textBackgroundComparing treatment effectiveness over time in observational settings is hampered by several major threats, among them confounding and attrition bias. ObjectivesTo develop European Alliance of Associations for Rheumatology (EULAR) points to consider (PtC) when analysing and reporting comparative effectiveness research using observational data in rheumatology. MethodsThe PtC were developed using a three-step process according to the EULAR Standard Operating Procedures. Based on a systematic review of methods currently used in comparative effectiveness studies, the PtC were formulated through two in-person meetings of a multidisciplinary task force and a two-round online Delphi, using expert opinion and a simulation study. Finally, feedback from a larger audience was used to refine the PtC. Mean levels of agreement amongst the task force were calculated. ResultsThree overarching principles and 10 PtC were formulated, addressing, in particular, potential biases relating to attrition or confounding by indication. Building on STROBE guidelines, these PtC insist on the definition of the baseline for analysis and treatment effectiveness. They also focus on the reasons for stopping treatment as an important consideration when assessing effectiveness. Finally, the PtC recommend providing key information on missingness patterns. ConclusionTo improve the reliability of an increasing number of real-world comparative effectiveness studies in rheumatology, special attention is required to reduce potential biases. Adherence to clear recommendations for the analysis and reporting of observational comparative effectiveness studies will improve the trustworthiness of their results.<br/
Pathway-specific Polygenic Risk Scores (PRS) identify OSA-related pathways differentially moderating genetic susceptibility to CAD
No full textBackground—Obstructive sleep apnea (OSA) and its features, such as chronic intermittent hypoxia (IH), may differentially affect specific molecular pathways and processes in the pathogenesis of coronary artery disease (CAD) and influence the subsequent risk and severity of CAD events. In particular, competing adverse (e.g. inflammatory) and protective (e.g. increased coronary collateral blood flow) mechanisms may operate, but remain poorly understood. We hypothesize that common genetic variation in selected molecular pathways influences the likelihood of CAD events differently in individuals with and without OSA, in a pathway-dependent manner. Methods—We selected a cross-sectional sample of 471,877 participants from the UK Biobank, among whom we ascertained 4,974 to have OSA, 25,988 to have CAD, and 711 to have both. We calculated pathway-specific polygenic risk scores (PS-PRS) for CAD, based on 6.6 million common variants evaluated in the CARDIoGRAMplusC4D genome-wide association study (GWAS), annotated tospecific genes and pathways using functional genomics databases. Based on evidence of involvement with IH and CAD, we tested PS-PRS for the HIF-1, VEGF, NFkB and TNF signaling pathways. Results—In a multivariable-adjusted logistic generalized additive model, elevated PS-PRSs for the KEGG VEGF pathway (39 genes) associated with protection for CAD in OSA (interaction odds ratio 0.86, p = 6E-04). By contrast, the genome-wide CAD PRS did not show evidence of statistical interaction with OSA.Conclusions—We find evidence that pathway-specific genetic risk of CAD differs between individuals with and without OSA in a qualitatively pathway-dependent manner, consistent with the previously studied phenomena whereby features of OSA may have both positive and negative effects on CAD. These results provide evidence that gene-by-environment interaction influences CAD riskin certain pathways among people with OSA, an effect that is not well-captured by the genome-wise wide PRS. These results can be followed up to study how OSA interacts with genetic risk at the molecular level, and potentially to personalize OSA treatment and reduce CAD risk according to individual pathway-specific genetic risk profiles