Micro-focussed XAFS spectroscopy to study Ni-bearing precipitates in the metal of corroded Zircaloy-2

The present work concerns an investigation of the local atomic environment of Ni-containing secondary phase precipitates (SPP) present in the metal-part of Zircaloy-2 cladding tubes. An unirradiated Zircaloy-2 and two specimens irradiated in a commercial nuclear power plant are characterized using μ-focussed synchrotron radiation, and by x-ray absorption fine structure (XAFS) spectroscopy. The patterns of Ni K-edge XANES and EXAFS of SPP in unirradiated and irradiated cladding are found different. Considering the fact that Ni-bearing SPP in the unirradiated samples are mainly Zintl phase Zr2(Fe, Ni) type, a detailed EXAFS analysis of near-neighbor Ni atoms has been made. The result of a curve fit for the first two shells shows that about 2 Ni(Fe) and 8Zr atoms are coordinated at2.68 and 2.77Å, respectively, around a central Ni atom in the SPP. XANES data analysis provides total electronic density of states at the Fermi level of unirradiated Zr2(Fe, Ni). At the Ni K-edge EXAFS spectra of irradiated SPP, however, only a single scattering peak is observed demonstrating the structural disorder introduced by the neutron irradiation. The coordination number of the Ni neighboring shells is reduced markedly due to the formation of point and extended defects in the damaged SPP lattice. Dissolution of Ni from the SPP is also evident from the data. The results of this study provide a further basis for the description of both crystallographic and electronic structures of intermetallic second-phase precipitates found in Zr-based alloy

Self-assembled ge nanostructures on polymer-coated silicon: growth and characterization

Self-assembled Ge nanoparticles have been grown on polymer-coated Si substrates by thermal evaporation under high vacuum utilizing the nonwetting condition given by the surface free-energy relation σ Ge»σpolymer. The nanostructures have been characterized by Raman spectroscopy, atomic-force microscopy (AFM), and optical microscopy. Raman spectrum shows a prominent Ge-Ge vibration peak at 302cm-1. AFM and optical microscopy show the formation of isolated Ge islands (>~100nm base, <~25nm height), nanowires (160 nm base, 25 nm height), and islands in linear chains. The possibility of embedding such nanostructures in waveguide structures are discussed

Desiring Dual Language Bilingual Education: One Community’s Perspectives on Past and Future Directions for Bilingual Learners

Perceptions and beliefs about past, present, and future bilingual educational programs were gathered from key members of a bilingual community, including teachers, parents, and educational administrators. Participants’ responses were analyzed and three overarching themes emerged. Current perceptions of bilingual education programs are strongly influenced by: (a) sociohistorical and political factors, (b) the effectiveness of instructional techniques; and (c) beliefs about bilingualism in general. Implications of these results are described with a focus on how they can inform policies and practices for bilingual learners

Fermentation and antimicrobial characteristics of Lactobacillus plantarum and Candida tropicalis from Nigerian fermented maize (akamu)

This study investigated the ability of Lactobacillus plantarum strains (NGL5 and NGL7) and Candida tropicalis (NGY1) previously identified from akamu-a Nigerian fermented maize food with probiotic L. plantarum LpTx and Saccharomyces boulardii SB20 to ferment ground maize slurries based on pH, acidity, microbial biomass, levels of sugars and organic acids, and their antimicrobial activity against Salmonella enterica serovar Enteritidis NCTC 5188, Escherichia coli NCTC 11560, Bacillus cereus NCIMB 11925, Staphylococcus aureus NCTC 3750 and Listeria monocytogenes NCTC 7973 using an agar spot assay. L. plantarum strains either as single or mixed starter cultures with the yeasts had growth rates ≥0.15 h-1,with pH significantly (p≤0.05) decreased to ≤3.93 after 12 h and then to ≤3.52 after 72 h and lactic acid >84 mmol L-1. The yeasts had growth rates ≥0.18 h-1 but pH was ≥4.57 with lactic acid levels ≤20.23 mmol L-1 after 72 h in the single culture fermentation. There was no inhibition in modified MRS agar: 0.2% glucose and 0.2% glucose without Tween 80. Inhibition halos in MRS agar varied from 10.6 to 23.9 mm. S. bourladii was more inhibitory towards L. monocytogenes (8.6 mm) and B. cereus (5.4 mm ) than was C. tropicalis (1.1 and 3.3 mm for L. monocytogenes NCTC 7973 and B. cereus NCIMB 11925 respectively) (0.9 mm) in malt extract agar. This study showed that C. tropicalis was less inhibitory to the pathogens while antimicrobial activities of the L. plantarum strains were mainly due to acidity and the L. plantarum strains either as single or mixed cultures with the yeasts demonstrated strong fermentation ability, with significant decrease in pH which is vital in the choice of starter for product safety

Changes in the biochemical and nutrient composition of seafood due to ocean acidification and warming

Ocean acidification and warming may threaten future seafood production, safety and quality by negatively impacting the fitness of marine species. Identifying changes in nutritional quality, as well as species most at risk, is crucial if societies are to secure food production. Here, changes in the biochemical composition and nutritional properties of the commercially valuable oysters, Magallana gigas and Ostrea edulis, were evaluated following a 12-week exposure to six ocean acidification and warming scenarios that were designed to reflect the temperature (+3 °C above ambient) and atmospheric pCO 2 conditions (increase of 350–600 ppm) predicted for the mid-to end-of-century. Results suggest that O. edulis, and especially M. gigas, are likely to become less nutritious (i.e. containing lower levels of protein, lipid, and carbohydrate), and have reduced caloric content under ocean acidification and warming. Important changes to essential mineral composition under ocean acidification and warming were evident in both species; enhanced accumulation of copper in M. gigas may be of concern regarding consumption safety. In light of these findings, the aquaculture industry may wish to consider a shift in focus toward species that are most robust to climate change and less prone to deterioration in quality, in order to secure future food provision and socio-economic benefits of aquaculture

Hospital Mortality and Trainee Experiences: How General Medical Council Survey Findings Correlate With Summary Hospital-Level Mortality Indicator.

OBJECTIVES: This study aimed to investigate whether components of junior doctor satisfaction are associated with patient mortality within the United Kingdom. METHODS: We conducted a cross-sectional study of publicly available data (the General Medical Council [GMC] National Survey and the Summary Hospital-level Mortality Indicator [SHMI]) pertaining to subjective physician trainee satisfaction and patient mortality within 80 United Kingdom-based healthcare institutions. The direction and strength of correlation between components of the GMC National Survey and relative patient mortality as described by the SHMI were calculated. Additional outcomes included mean GMC survey scores for reported domains and mean SHMI by healthcare institution. RESULTS: SHMI for included healthcare institutions ranged from 0.69 to 1.21 (mean [SD], 1.01 [0.1]). Mean GMC domain scores ranged between 44.61 and 88.62 (mean [SD], 71.16 [10.84]). Statistically significant correlations were observed for clinical supervision, clinical supervision out of hours, rota design, overall satisfaction, and teamwork. After application of Bonferroni correction, statistically significant correlations remained for both clinical supervision and clinical supervision out of hours. CONCLUSIONS: There is a significant association between components of subjective trainee satisfaction and patient mortality within the United Kingdom. Further investigation to examine these relationships, perhaps to target intervention, may prevent avoidable patient harm

Delays in Multiple Sclerosis diagnosis (DIMES): protocol for a multicentre, observational study of multiple sclerosis diagnostic pathways in the United Kingdom and Republic of Ireland.

BACKGROUND: Multiple sclerosis (MS) is a leading cause of non-traumatic disability in young adults. Accumulating evidence indicates early diagnosis and early treatment improves long-term outcomes. However, the MS diagnostic pathway is increasingly complex, and delays may occur at several stages. Factors causing delays remain understudied. We aim to quantify the time taken for MS to be diagnosed, and characterise the diagnostic pathway and initial care provided, in the United Kingdom (UK) and Republic of Ireland (ROI). METHODS: Delays In MultiplE Sclerosis diagnosis (DIMES) in the UK and ROI is a multicentre, observational, retrospective study that will be conducted via the Neurology and Neurosurgery Interest Group (NANSIG) collaborative network. Any hospital in the UK and ROI providing an MS diagnostic service is eligible to participate. Data on consecutive individuals newly diagnosed with MS between 1st July 2022 and 31st December 2022 will be collected. The primary outcomes are 1) time from symptoms/signs prompting referral to neurology, to MS diagnosis; and 2) time from referral to neurology for suspected MS, to MS diagnosis. Secondary outcomes include: MS symptoms, referring specialties, investigations performed, neurology appointments, functional status, use of disease modifying treatments, and support at diagnosis including physical activity, and follow up. Demographic characteristics of people newly diagnosed with MS will be summarised, adherence to quality standards summarised as percentages, and time-to-event variables presented with survival curves. Multivariable models will be used to investigate the association of demographic and clinical factors with time to MS diagnosis, as defined in our primary outcomes. DISCUSSION: DIMES aims to be the largest multicentre study of the MS diagnostic pathway in the UK and ROI. The proposed data collection provides insights that cannot be provided from contemporary registries, and the findings will inform approaches to MS services nationally in the future

Supervision, scheduling, satisfaction and shared working: how experiences of junior doctors relate to excess mortality within the NHS.

BACKGROUND: We sought to explore associations between trainee doctor perception and excess patient mortality. METHODS: Data from two publicly available databases reflecting mortality and components of trainee satisfaction within 81 NHS healthcare institutions between the years 2012 and 2019 were analysed. Pearson's correlation coefficients were calculated. RESULTS: All domains of trainee perception were correlated with excess mortality. Clinical supervision out of hours (R=-0.44; p<0.0001), teamwork (R=-0.36; p<0.0001) and clinical supervision at any time (R=-0.35; p<0.0001) were most strongly correlated. Most associations remained consistent year on year. CONCLUSION: Trainee doctor perceptions of clinical supervision, rota design and teamwork within the NHS are consistently correlated with excess patient mortality. Further exploration of these associations could identify opportunities for interventions to reduce excess patient mortality. Given the clinical significance of our findings, organisations should consider rapid implementation of evidence-based interventions where they exist