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Associations between unmet needs for daytime activities and company and scores on the Neuropsychiatric Inventory-Questionnaire in people with dementia: a longitudinal study
Get PDFObjectives To examine prospectively the association between unmet needs for daytime activities and company and behavioural and psychological symptoms of dementia. Methods We included 451 people with mild or moderate dementia, from eight European countries, who were assessed three times over 12 months. Unmet needs were measured with the Camberwell Assessment of Need for the Elderly. Three sub-syndromes of the Neuropsychiatric Inventory-Questionnaire were regressed, one-by-one, against unmet needs for daytime activities and company, adjusting for demographic and clinical-functional covariates. Results Unmet needs for daytime activities were associated with more affective symptoms at baseline, six and twelve months, mean 0.74 (p < 0.001), 0.76 (p < 0.001) and 0.78 (p = 0.001) points higher score respectively, and with more psychotic symptoms at baseline (mean 0.39 points, p = 0.007) and at six months follow-up (mean 0.31 points, p = 0.006). Unmet needs for company were associated with more affective symptoms at baseline, six and twelve months, mean 0.44 (p = 0.033), 0.67 (p < 0.001) and 0.91 (p < 0.001) points higher score respectively, and with more psychotic symptoms at baseline (mean 0.40 points, p = 0.005) and at six months (mean 0.35 points, p = 0.002) follow-up. Conclusion Interventions to reduce unmet needs for daytime activities and company could reduce affective and psychotic symptoms in people with dementia
A comprehensive framework for assessing the accuracy and uncertainty of global above-ground biomass maps
Get PDFOver the past decade, several global maps of above-ground biomass (AGB) have been produced, but they exhibit significant differences that reduce their value for climate and carbon cycle modelling, and also for national estimates of forest carbon stocks and their changes. The number of such mapsis anticipated to increase because of new satellite missions dedicated to measuring AGB. Objective and consistent methods to estimate the accuracy and uncertainty of AGB maps are therefore urgently needed. This paper develops and demonstrates a framework aimed at achieving this. The framework provides a means to compare AGB maps with AGB estimates from a global collectionof National Forest Inventories and research plots that accounts for the uncertainty of plot AGB errors.This uncertainty depends strongly on plot size, and is dominated by the combined errors from tree measurements and allometric models (inter-quartile range of their standard deviation (SD) = 30-151 Mg ha-1). Estimates of sampling errors are also important, especially in the most commoncase where plots are smaller than map pixels (SD = 16-44 Mg ha-1). Plot uncertainty estimates are used to calculate the minimum-variance linear unbiased estimates of the mean forest AGB when averaged to 0.1◦. These are used to assess four AGB maps: Baccini (2000), GEOCARBON (2008),GlobBiomass (2010) and CCI Biomass (2017). Map bias, estimated using the differences between the plot and 0.1◦ map averages, is modelled using Random Forest regression driven by variables shown to affect the map estimates. The bias model is particularly sensitive to the map estimate of AGB and tree cover, and exhibits strong regional biases. Variograms indicate that AGB map errorshave map-specific spatial correlation up to a range of 50-104 km, which increases the variance of spatially aggregated AGB map estimates compared to when pixel errors are independent. After bias adjustment, total pantropical AGB and its associated SD are derived for the four map epochs.This total becomes closer to the value estimated by the Forest Resources Assessment every after epoch and shows a similar decrease. The framework is applicable to both local and global-scale analysis, and is available at https://github.com/arnanaraza/PlotToMap. Our study therefore constitutesa major step towards improved AGB map validation and improvement
Current costs of dialysis modalities:A comprehensive analysis within the United Kingdom
Get PDFBACKGROUND: Previous evidence suggests home-based dialysis to be more cost-effective than unit-based or hospital-based dialysis. However, previous analyses to quantify the costs of different dialysis modalities have used varied perspectives, different methods, and required assumptions due to lack of available data. The National Institute for Health and Care Excellence reports uncertainty about the differences in costs between home-based and unit-based dialysis. This uncertainty limits the ability of policy makers to make recommendations based on cost effectiveness, which also impacts on the ability of budget holders to model the impact of any service redesign and to understand which therapies deliver better value. The aim of our study was to use a combination of top-down and bottom-up costing methods to determine the direct medical costs of different dialysis modalities in one UK nation (Wales) from the perspective of the National Health Service (NHS).METHODS: Detailed hybrid top-down and bottom-up micro-costing methods were applied to estimate the direct medical costs of dialysis modalities across Wales. Micro-costing data was obtained from commissioners of the service and from interviews with renal consultants, nurses, accountants, managers and allied health professionals. Top-down costing information was obtained from the Welsh Renal Clinical Network (who commission renal services across Wales) and the Welsh Ambulance Service Trust.RESULTS: The annual direct cost per patient for home-based modalities was £16,395 for continuous ambulatory peritoneal dialysis (CAPD), £20,295 for automated peritoneal dialysis (APD) and £23,403 for home-based haemodialysis (HHD). The annual cost per patient for unit-based modalities depended on whether or not patients required ambulance transport. Excluding transport, the cost of dialysis was £19,990 for satellite units run in partnership with independent sector providers and £23,737 for hospital units managed and staffed by the NHS. When ambulance transport was included, the respective costs were £28,931 and £32,678, respectively.CONCLUSION: Our study is the most comprehensive analysis of the costs of dialysis undertaken thus far in the United Kingdom and clearly demonstrate that CAPD is less costly than other dialysis modalities. When ambulance transport costs are included, other home therapies (APD and HHD) are also less costly than unit-based dialysis. This detailed analysis of the components that contribute to dialysis costs will help inform future cost-effectiveness studies, inform healthcare policy and drive service redesign.</p
Subsequent full publication of qualitative studies presented at United Kingdom Royal College of Nursing Research Conference 2015 and 2016:A follow-up study
Get PDFA considerable proportion of quantitative research remains unpublished once completed. Little research has documented non-dissemination and dissemination bias in qualitative research. This study aimed to generate evidence on the extent of non-dissemination in qualitative research. We followed a cohort of qualitative studies presented as conference abstracts to ascertain their subsequent publication status. We searched for subsequent full publication in MEDLINE, in the Cumulative Index to Nursing & Allied Health Literature and in Google Scholar. We matched abstracts to subsequent publications according to authors, method of data collection and phenomenon of interest. Fisher's exact test was calculated to examine associations between study characteristics and publication. Factors potentially associated with time to publication were evaluated with Cox regression analysis. For 91 of 270 included abstracts (33.70%; 95% CI 28.09%-39.68%), no full publication was identified. Factors that were found to be associated with subsequent full publication were oral presentation (OR 4.62; 95% CI 2.43-8.94) and university affiliation (OR 1.96; 95% CI 1.05-3.66). Compared to oral presentations, studies presented as posters took longer time to reach full publication (hazard ratio 0.35, 95% CI 0.21-0.58). This study shows that it was not possible to retrieve a full publication for over one-third of abstracts. Our findings suggest that where this non-dissemination is systematic, it may lead to distortions of the qualitative evidence-base for decision-making through dissemination bias. Our findings are congruent with those of other studies. Further research might investigate non-dissemination of qualitative studies in other disciplines to consolidate our findings.</p
Pilot scale extraction of protein from cold and hot-pressed rapeseed cake: Preliminary studies on the effect of upstream mechanical processing
Get PDFIt is important from a techno-economic perspective to understand the challenges associated with developing scalable processes to extract functional proteins from rapeseed cake for applications as functional food ingredients. One of these challenges is to develop a better understanding of the link between upstream mechanical processing of the rapeseed cake and the yield of extracted protein. An initial trial with cold pressed rapeseed cake (CPR) indicated that wet milling had no impact on protein yield. Measurement of protein yields with the Bradford assay indicated that 14% would be recovered. The total protein recovered (5.4% by Kjeldahl analysis) contained a glucosinolate and phytate content that was similar to the rapeseed cake at the start of the process. The fate of the protein extraction was followed during a pilot scale trial with hot-pressed rapeseed cake (HPR), using only stirring followed by sieving, revealing an increase in protein yields, as determined by the Bradford assay, from 8.0% at the start to 22.6% at the end of processing. In addition, only 16% of HPR was solubilized. A similar pilot scale trial with HPR using wet milling and stirring followed by decanting also showed an increase in protein concentration from 15.3% at the start to 23.7% at the end of processing. In addition, 38% of HPR was solubilized. This study provides an insight into what the effect of upstream mechanical processing (wet milling) has in releasing protein from rapeseed cake in order to improve process efficiency. This could have important consequences for upscaling and commercial extraction of rapeseed cake protein
A framework to understand the role of biological time in responses to fluctuating climate drivers
Get PDFUnderstanding biological responses to environmental fluctuations (e.g. heatwaves) is a critical goal in ecology. Biological responses (e.g. survival) are usually measured with respect to different time reference frames, i.e. at specific chronological times (e.g. at specific dates) or biological times (e.g. at reproduction). Measuring responses on the biological frame is central to understand how environmental fluctuation modifies fitness and population persistence. We use a framework, based on partial differential equations (PDEs) to explore how responses to the time scale and magnitude of fluctuations in environmental variables (= drivers) depend on the choice of reference frame. The PDEs and simulations enabled us to identify different components, responsible for the phenological and eco-physiological effects of each driver on the response. The PDEs also highlight the conditions when the choice of reference frame affects the sensitivity of the response to a driver and the type of join effect of two drivers (additive or interactive) on the response. Experiments highlighted the importance of studying how environmental fluctuations affect biological time keeping mechanisms, to develop mechanistic models. Our main result, that the effect of the environmental fluctuations on the response depends on the scale used to measure time, applies to both field and laboratory conditions. In addition, our approach, applied to experimental conditions, can helps us quantify how biological time mediates the response of organisms to environmental fluctuations.</p
Metagenomic Mining for Esterases in the Microbial Community of Los Rueldos Acid Mine Drainage Formation
Get PDFAcid mine drainage (AMD) systems are extremely acidic and are metal-rich formations inhabited by relatively low-complexity communities of acidophiles whose enzymes remain mostly uncharacterized. Indeed, enzymes from only a few AMD sites have been studied. The low number of available cultured representatives and genome sequences of acidophiles inhabiting AMDs makes it difficult to assess the potential of these environments for enzyme bioprospecting. In this study, using naïve and in silico metagenomic approaches, we retrieved 16 esterases from the α/β-hydrolase fold superfamily with the closest match from uncultured acidophilic Acidobacteria, Actinobacteria (Acidithrix, Acidimicrobium, and Ferrimicrobium), Acidiphilium, and other Proteobacteria inhabiting the Los Rueldos site, which is a unique AMD formation in northwestern Spain with a pH of ∼2. Within this set, only two polypeptides showed high homology (99.4%), while for the rest, the pairwise identities ranged between 4 and 44.9%, suggesting that the diversity of active polypeptides was dominated not by a particular type of protein or highly similar clusters of proteins, but by diverse non-redundant sequences. The enzymes exhibited amino acid sequence identities ranging from 39 to 99% relative to homologous proteins in public databases, including those from other AMDs, thus indicating the potential novelty of proteins associated with a specialized acidophilic community. Ten of the 16 hydrolases were successfully expressed in Escherichia coli. The pH for optimal activity ranged from 7.0 to 9.0, with the enzymes retaining 33–68% of their activities at pH 5.5, which was consistent with the relative frequencies of acid residues (from 54 to 67%). The enzymes were the most active at 30–65°C, retaining 20–61% of their activity under the thermal conditions characterizing Los Rueldos (13.8 ± 0.6°C). The analysis of the substrate specificity revealed the capacity of six hydrolases to efficiently degrade (up to 1,652 ± 75 U/g at pH 8.0 and 30°C) acrylic- and terephthalic-like [including bis(2-hydroxyethyl)-terephthalate, BHET] esters, and these enzymes could potentially be of use for developing plastic degradation strategies yet to be explored. Our assessment uncovers the novelty and potential biotechnological interest of enzymes present in the microbial populations that inhibit the Los Rueldos AMD system