272 research outputs found
Dietitians' practice in giving carbohydrate advice in the management of type 2 diabetes: a mixed methods study
Background: Carbohydrate is accepted as the principal nutrient affecting blood glucose in diabetes; however, current guidelines are unable to specify the optimal quantity of carbohydrate for glycaemic control. No studies exist that describe current practice amongst healthcare professionals giving carbohydrate advice in type 2 diabetes. The present study aims to improve understanding of the degree of variation in the current practice of UK registered dietitians (RDs) by describing how RDs advise patients.
Methods: UK RDs were contacted through national networks and asked to complete an online survey, which was analysed using stata, version 12 (StataCorp, College Station, TX, USA). Three consultations between dietitians and patients with type 2 diabetes were observed, followed by semi-structured interviews with the dietitians.
Results: In total, 320 complete survey responses were received. Dietitians' advice varied according to expertise, training and confidence, and the complexity of the patient's blood glucose treatment. Some 48% (n = 154) of respondents advised patients to restrict carbohydrate intake either occasionally or frequently, with 35.6% (n = 114) considering 30â39% of total energy from carbohydrate to be a realistic expectation. The overall theme from the interviews was âConflicting Prioritiesâ, with three sub-themes: (i) how treatment decisions are made; (ii) the difference between empowerment and advice; and (iii) contradictory advice. A disparity existed between what was observed and interview data on how dietitians rationalise the type of carbohydrate advice provided.
Conclusions: Dietitians' advice varies for a number of reasons. Consensus exists in some areas (e.g. carbohydrate awareness advice); however, clear definitions of such terms are lacking. Clarification of interventions may improve the consistency of approach and improve patient outcomes
Discours III.
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are increasingly used to
reconstruct past terrestrial temperature and soil pH. Here we compare all available
modern soil brGDGT data (n=350) to a wide range of environmental parameters to
obtain new global temperature calibrations.
We show that soil moisture index (MI), a modeled parameter that also takes
potential evapotranspiration into account, is correlated to the 6-methyl brGDGT
distribution but does not significantly control the distribution of 5-methyl brGDGTs.
Instead, temperature remains the primary control on 5-methyl brGDGTs. We propose the following global calibrations: MAAT soil = 40.01 x MBTâ5me â 15.25 (n=350, R2 22 = 23 0.60, RMSE = 5.3 °C) and growing degree days above freezing (GDD0 soil) = 14344.3 x MBTâ5me - 4997.5 (n=350, R2 24 = 0.63, RMSE = 1779 °C).
Recent studies have suggested that factors other than temperature can impact
arid and/or alkaline soils dominated by 6-methyl brGDGTs. As such, we develop new
global temperature calibrations using samples dominated by 5-methyl brGDGTs only
(IR6me<0.5). These new calibrations have significantly improved correlation
coefficients and lower root mean square errors (RMSE) compared to the global
calibrations: MAATsoilâ = 39.09 x !"#!!"
! â 14.50 (n=177, R2 30 = 0.76, RMSE =
4.1 °C) and GDD0 soilâ = 13498.8 x !"#!!"
! â 4444.5 (n=177, R2 31 = 0.78, RMSE =
1326). We suggest that these new calibrations should be used to reconstruct terrestrial
climate in the geological past; however, care should be taken when employing these
calibrations outside the modern calibration rangThis research was funded through the advanced ERC grant `The greenhouse earth
412 system' (T-GRES, project reference 340923). R.D.P. acknowledges the Royal Society
413 Wolfson Research Merit Award
The Implementation Of Problem Based Learnin g Model Toward Conceptual Understanding At Senior High School
Installing the "magic methyl" - C-H methylation in synthesis
The selective and efficient C-H methylation of sp2 and sp3 carbon centres has become a powerful transformation in the synthetic toolbox. Due to the potential for profound changes to physicochemical properties attributed to the installation of a "Magic Methyl" group at a strategic site in a lead compound, such techniques have become highly desirable in modern drug discovery and synthesis programmes. This review will cover the diverse techniques that have been employed to enable the selective installation of the C-Me bond in a wide range of chemical structures, from simple building blocks to complex drug-like architectures
Distributions of geohopanoids in peat: Implications for the use of hopanoid-based proxies in natural archives
This is the final version of the article. Available from Elsevier via the DOI in this record.Hopanoids are pentacyclic triterpenoids produced by a wide range of bacteria. Within modern settings, hopanoids mostly occur in the biological 17β,21β(H) configuration. However, in some modern peatlands, the C31 hopane is present as the âthermally-matureâ 17Îą,21β(H) stereoisomer. This has traditionally been ascribed to isomerisation at the C-17 position catalysed by the acidic environment. However, recent work has argued that temperature and/or hydrology also exert a control upon hopane isomerisation. Such findings complicate the application of geohopanoids as palaeoenvironmental proxies. However, due to the small number of peats that have been studied, as well as the lack of peatland diversity sampled, the environmental controls regulating geohopanoid isomerisation remain poorly constrained. Here, we undertake a global approach to investigate the occurrence, distribution and diagenesis of geohopanoids within peat, combining previously published and newly generated data (nâŻ=âŻ395) from peatlands with a wide temperature (â1 to 27âŻÂ°C) and pH (3â8) range. Our results indicate that peats are characterised by a wide range of geohopanoids. However, the C31 hopane and C32 hopanoic acid (and occasionally the C32 hopanol) typically dominate. C32 hopanoic acids occur as ιβ- and ββ-stereoisomers, with the ββ-isomer typically dominating. In contrast, C31 hopanes occur predominantly as the ιβ-stereoisomer. These two observations collectively suggest that isomerisation is not inherited from an original biological precursor (i.e. biohopanoids). Using geohopanoid ββ/(ιβâŻ+âŻÎ˛Î˛) indices, we demonstrate that the abundance of ιβ-hopanoids is strongly influenced by the acidic environment, and we observe a significant positive correlation between C31 hopane isomerisation and pH (nâŻ=âŻ94, r2âŻ=âŻ0.64, pâŻ1 pH unit) and longer-term (>1âŻkyr) variation. Overall, our findings demonstrate the potential of geohopanoids to provide unique new insights into understanding depositional environments and interpreting terrestrial organic matter sources in the geological record.This research was funded through the advanced ERC grant âThe Greenhouse Earth Systemâ (T-GRES. Project reference: 340923). RDP acknowledges the Royal Society Wolfson Research Merit Award. YZ thanks the National Natural Science Foundation of China (Project reference: 41372033). ELM acknowledges the Philip Leverhulme Prize. We also thank the NERC Life Sciences Mass Spectrometry Facility (Bristol) for analytical support and D. Atkinson for help with the sample preparation. GNI thanks Janet Dehmer and Philippe Schaeffer for helpful discussions. Members of the T-GRES Peat Database collaborators are M.J. Amesbury, H. Biester, R. Bindler, J. Blewett, M.A. Burrows, D. del Castillo Torres, F.M. Chambers, A.D. Cohen, S.J. Feakins, M. GaĹka, A. Gallego-Sala, L. Gandois, D.M. Gray, P.G. Hatcher, E.N. Honorio Coronado, P.D.M. Hughes, A. Huguet, M. KĂśnĂśnen, F. Laggoun-DĂŠfarge O. Lähteenoja, M. Lamentowicz, R. Marchant, X. Pontevedra-Pombal, C. Ponton, A. Pourmand, A.M. Rizzuti, L. Rochefort, J. Schellekens, F. De Vleeschouwer. Finally, we thank Darci Rush, Phil Meyers and an anonymous reviewer for their comments and thoughtful suggestions which greatly improved this manuscript
The political economy of high skills:Higher Education in knowledge-based labour markets
<p>A successful transition into the knowledge economy depends upon higher level skills, creating unprecedented pressure on university systems to provide labour markets with the skills needed. But what are the political economy dynamics underlying national patterns of high skill formation? The article proposes a framework to theorize the relationship between higher education systems and knowledge-based labour markets based on two dimensions: the type of knowledge economy predominant in a given country and the extent of inter-university competition. It is argued that the former explains what type of higher level skills will be sought by employers and cultivated by governments, while the latter helps us understanding why some higher education systems are more open to satisfying labour market demands compared to others. A set of diverse country case studies (Britain, Germany, South Korea and the Netherlands) is employed to illustrate the theory.</p
Concerns about losing face moderate the effect of visual perspective on health-related intentions and behaviors
Visualizing oneself engaging in future actions has been shown to increase the likelihood of actually engaging in the visualized action. In three studies, we examined the effect of perspective taken to visualize a future action (first-person vs. third-person) as a function of the degree to which individuals worry about othersâ evaluation of themselves (face) and whether the visualized behavior is public or private. Across all studies, the effect of visual perspective was present only for participants with high level of face. In this group, the third-person visualization induced stronger intentions to engage in the behavior when the imagined behavior was public (Study 1), whereas the first-person visualization induced stronger intentions and greater likelihood to engage in that behavior when it was private (Study 2). The influence of the first-person perspective on flossing behavior was eliminated when people with high levels of face were encouraged to consider inter-personal consequences of the action (Study 3). Results are discussed in the light of recent theorizing on the cognitive consequences of taking a third-person versus a first-person perspective in visual imagery
Recommended from our members
A randomised controlled trial of treatments of childhood anxiety disorder in the context of maternal anxiety disorder: clinical and cost-effectiveness outcomes
Background: This study evaluated whether clinical and economic outcomes from CBT for child anxiety disorders in the context of maternal anxiety disorders are improved by adding treatment focused on (i) maternal anxiety disorders, or (ii) mother-child interactions. Methods: 211 children (7 â 12 years, 85% White British, 52% female) with a primary anxiety disorder, whose mothers also had a current anxiety disorder, were randomised to receive (i) child-focused CBT with non-specific control interventions (CCBT+Con), (ii) CCBT with CBT for the maternal anxiety disorder (CCBT+MCBT), or (iii) CCBT with an intervention targeting the mother-child interaction (CCBT+MCI). A cost-utility analysis from a societal perspective was conducted using mother/child combined Quality Adjusted Life Years (QALYs). [Trial registration: https://doi.org/10.1186/ISRCTN19762288]. Results: MCBT was associated with immediate reductions in maternal anxiety compared to the non-specific control; however, after children had also received CCBT, maternal outcomes in the CCBT+MCI and CCBT+Con arms improved and CCBT+MCBT was no longer superior. Neither CCBT+MCBT nor CCBT+MCI conferred a benefit over CCBT+Con in terms of child anxiety disorder diagnoses post-treatment [primary outcome] (adj RR: 1.22 (95% CI 0.88, 1.67), p = .23; adj RR: 1.21 (95% CI 0.88, 1.65), p = .24 respectively) or global improvement ratings (adj RR 1.25 (95% CI 0.99, 1.57), p = .06; adj RR 1.18 (95% CI 0.93, 1.50), p = .17) or six and 12 months later. No significant differences between the groups were found on the main economic outcome measures (child/mother combined QALY mean difference: CCBT+MCBT vs CCBT+Con: -0.04 (95% CI -0.12, 0.04), p = 0.29; CCBT+MCI vs CCBT+Con: 0.02 (95% CI -0.05, -0.09), p = 0.54). CCBT+MCI was associated with non-significantly higher costs than CCBT (mean difference: ÂŁ154 (95% CI -ÂŁ1239, ÂŁ1547), p = 0.83) but, when taking into account sampling uncertainty, it may be cost-effective compared with CCBT alone. Conclusions: Good outcomes were achieved for children and their mothers across treatment arms. There was no evidence of significant clinical benefit from supplementing CCBT with either CBT for the maternal anxiety disorder or treatment focussed on mother-child interactions, but the addition of MCI (and not MCBT) may be cost-effective. Keywords: Child; anxiety; mother; parent-child interaction; CBT
Effects of temperature and pH on archaeal membrane lipid distributions in freshwater wetlands
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record. âŻFreshwater wetlands harbour diverse archaeal communities and associated membrane lipid assemblages, but the effect of environmental factors (e.g. pH and temperature) on the distribution of these lipids is relatively poorly constrained. Here we explore the effects of temperature and pH on archaeal core-lipid and intact polar lipid (IPL) derived core lipid distributions in a range of wetlands. We focus not only on the commonly studied isoprenoidal glycerol dialkyl glycerol tetraethers (isoGDGTs), but also widen our analyses to include more recently identified but relatively widespread archaeal lipids such as isoGDGT isomers, methylated isoGDGTs (Me-GDGTs), and butanetriol and pentanetriol tetraethers (BDGTs and PDGTs). Based on multivariate analysis and a globally distributed set of wetlands, we find that the degree of isoGDGT cyclisation does increase along with temperature and pH in wetlands; however and unlike in some other settings, this relationship is obscured in simple scatterplots due to the incorporation of isoGDGTs from highly diverse archaeal sources with multiple ring-temperature or ring-pH relationships. We further show that the relative abundance of early eluting to later eluting isoGDGT isomers increases with pH, representing a previously unknown and seemingly widespread archaeal membrane homeostasis mechanism or taxonomic signal. The distribution and abundance of crenarchaeol, a marker for Thaumarchaeota, demonstrates that in wetlands these Archaea, likely involved in ammonia oxidation, are restricted primarily to the generally dryer, soil/sediment surface and typically are more abundant in circumneutral pH settings. We identify Me-GDGTs and Me-isoGMGTs (homologs of isoGDGTs and isoGMGTs, but with additional methylation on the biphytanyl chain) as being ubiquitous in wetlands, but variation in their abundance and distribution suggests changing source communities and/or membrane adaptation. The high relative abundance of BDGTs and PDGTs in the perennially anoxic part of the peat profile (catotelm) as well as their elevated abundance in a circumneutral pH wetland is consistent with an important input from their only known culture source, the methanogenic Methanomassiliicoccales. Our results underline the diversity of archaeal membrane lipids preserved in wetlands and provide a baseline for the use of archaeal lipid distributions in wetlands as tracers of recent or ancient climate and biogeochemistry.NERCRoyal SocietyER
The tropical peatland archaeal lipidome â influence of vegetation and redox on diversity
This is the final version. Available from the European Association of Geoscientists & Engineers via the DOI in this record.âŻThe nature, variability, and diversity of environmental microbiomes and lipidomes are vital to understanding soil health, biogeochemical processes and reconstructing past climates. Such research on peatlands â especially tropical peatlands â is limited, despite their importance to the global carbon cycle through the sequestration of organic matter (OM) and production of methane. Here, we explore the distribution of archaea and their isoprenoidal glycerol dialkyl glycerol tetraether lipids (isoGDGTs) across a range of wetlands, in order to ascertain the controls on their distribution. We focus specifically on vegetation and OM composition to explore the relationships between archaeal ecology and carbon cycling in tropical contexts.
Through international collaboration, we created a database of core archaeal and bacteria lipid distributions of hundreds of peats from globally widespread sites (the TGRES Peat Database, Naafs et al., 2017). This formed the basis for peat-specific temperature and pH proxies based on the distribution of bacterial branched GDGTs as initially pioneered for mineral soils. However, clear environmental controls and patterns in the distribution of archaeal lipids are ambiguous (Naafs et al., 2018). For example, isoGDGT-5 is restricted to high temperature and low pH settings, but other isoGDGT and overly methylated isoprenoidal GDGT (Me-GDGTs) ring indices are poorly correlated with temperature and pH (Blewett et al., 2020). This suggests that in comparison to previously established GDGT-based environmental proxies the archaeal GDGTs of peatlands derive from an ecologically diverse group of organisms that confound simple environmental comparisons. Given the increased recognition of archaeal metabolic diversity, including a range of heterotrophic, methanotrophic and methanogen ecologies, it seems likely that changes in vegetation, peat OM composition and water level depth will impose significant controls on the archaeal community â and that of the lipids they produce
- âŚ