72,952 research outputs found

    Relationship between antihypertensive medications and cognitive impairment: Part I. review of human studies and clinical trials

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    Purpose of review: There is an established association between hypertension and increased risk of poor cognitive performance and dementia including Alzheimer’s disease; however, associations between antihypertensive medications (AHMs) and dementia risk are less consistent. An increased interest in AHM has resulted in expanding publications; however, none of the recent reviews are comprehensive. Our extensive review includes 15 observational and randomized controlled trials (RCTs) published over the last 5 years, assessing the relationship between AHM and cognitive impairment. Recent findings: All classes of AHM showed similar result patterns in human studies with the majority of study results reporting point estimates below one and only a small number of studies (N = 15) reporting statistically significant results in favor of a specific class. Summary: Only a small number of studies reported statistically significant results in favor of a specific class of AHM. Methodological limitations of the studies prevent definitive conclusions. Further work is now needed to evaluate the class of AHM and cognitive outcomes in future RCTs, with a particular focus on the drugs with the promising results in both animals and human observational studies

    Metabolic flexibility as a major predictor of spatial distribution in microbial communities

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    A better understand the ecology of microbes and their role in the global ecosystem could be achieved if traditional ecological theories can be applied to microbes. In ecology organisms are defined as specialists or generalists according to the breadth of their niche. Spatial distribution is often used as a proxy measure of niche breadth; generalists have broad niches and a wide spatial distribution and specialists a narrow niche and spatial distribution. Previous studies suggest that microbial distribution patterns are contrary to this idea; a microbial generalist genus (Desulfobulbus) has a limited spatial distribution while a specialist genus (Methanosaeta) has a cosmopolitan distribution. Therefore, we hypothesise that this counter-intuitive distribution within generalist and specialist microbial genera is a common microbial characteristic. Using molecular fingerprinting the distribution of four microbial genera, two generalists, Desulfobulbus and the methanogenic archaea Methanosarcina, and two specialists, Methanosaeta and the sulfate-reducing bacteria Desulfobacter were analysed in sediment samples from along a UK estuary. Detected genotypes of both generalist genera showed a distinct spatial distribution, significantly correlated with geographic distance between sites. Genotypes of both specialist genera showed no significant differential spatial distribution. These data support the hypothesis that the spatial distribution of specialist and generalist microbes does not match that seen with specialist and generalist large organisms. It may be that generalist microbes, while having a wider potential niche, are constrained, possibly by intrageneric competition, to exploit only a small part of that potential niche while specialists, with far fewer constraints to their niche, are more capable of filling their potential niche more effectively, perhaps by avoiding intrageneric competition. We suggest that these counter-intuitive distribution patterns may be a common feature of microbes in general and represent a distinct microbial principle in ecology, which is a real challenge if we are to develop a truly inclusive ecology

    Specifying ODP computational objects in Z

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    The computational viewpoint contained within the Reference Model of Open Distributed Processing (RM-ODP) shows how collections of objects can be configured within a distributed system to enable interworking. It prescribes certain capabilities that such objects are expected to possess and structuring rules that apply to how these objects can be configured with one another. This paper highlights how the specification language Z can be used to formalise these capabilities and the associated structuring rules, thereby enabling specifications of ODP systems from the computational viewpoint to be achieved

    Building Data-Driven Pathways From Routinely Collected Hospital Data:A Case Study on Prostate Cancer

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    Background: Routinely collected data in hospitals is complex, typically heterogeneous, and scattered across multiple Hospital Information Systems (HIS). This big data, created as a byproduct of health care activities, has the potential to provide a better understanding of diseases, unearth hidden patterns, and improve services and cost. The extent and uses of such data rely on its quality, which is not consistently checked, nor fully understood. Nevertheless, using routine data for the construction of data-driven clinical pathways, describing processes and trends, is a key topic receiving increasing attention in the literature. Traditional algorithms do not cope well with unstructured processes or data, and do not produce clinically meaningful visualizations. Supporting systems that provide additional information, context, and quality assurance inspection are needed. Objective: The objective of the study is to explore how routine hospital data can be used to develop data-driven pathways that describe the journeys that patients take through care, and their potential uses in biomedical research; it proposes a framework for the construction, quality assessment, and visualization of patient pathways for clinical studies and decision support using a case study on prostate cancer. Methods: Data pertaining to prostate cancer patients were extracted from a large UK hospital from eight different HIS, validated, and complemented with information from the local cancer registry. Data-driven pathways were built for each of the 1904 patients and an expert knowledge base, containing rules on the prostate cancer biomarker, was used to assess the completeness and utility of the pathways for a specific clinical study. Software components were built to provide meaningful visualizations for the constructed pathways. Results: The proposed framework and pathway formalism enable the summarization, visualization, and querying of complex patient-centric clinical information, as well as the computation of quality indicators and dimensions. A novel graphical representation of the pathways allows the synthesis of such information. Conclusions: Clinical pathways built from routinely collected hospital data can unearth information about patients and diseases that may otherwise be unavailable or overlooked in hospitals. Data-driven clinical pathways allow for heterogeneous data (ie, semistructured and unstructured data) to be collated over a unified data model and for data quality dimensions to be assessed. This work has enabled further research on prostate cancer and its biomarkers, and on the development and application of methods to mine, compare, analyze, and visualize pathways constructed from routine data. This is an important development for the reuse of big data in hospitals

    International Group Work for Sustainable Chemistry

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    As part of a transnational degree programme, students in the UK and China were linked together to carry out group work. This was enabled by having two versions of our FHEQ Level 4 Sustainable Chemistry module; in person for UK students, and by distance learning for Chinese students. Groups were instructed to discuss issues relating to the UN Sustainable Development Goals in their respective countries and report back individually. Students who found the assignment interesting were more likely to indicate they would keep in touch, while those students who had fewer interactions or found the assessment guidelines unclear found the assignment less interesting and were less likely to wish to remain in touch. This kind of assignment is an example of what can be done with links to other institutions around the world

    Caracterisation Sensorielle, Physico-Chimique Et Microbiologique Du Beurre De Karite, Vitellaria paradoxa Des Marches De Cote D\'Ivoire

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    Les beurres de karité des marchés de Côte d\'Ivoire présentent des couleurs, odeurs et textures diverses, mais les beurres jaunes (67,9 %), rancis (33,99 %) et compacts (93,83 %) sont les plus dominants. Les caractéristiques physico-chimiques varient d\'une couleur à une autre. Les beurres de karité beige et jaune enregistrent des valeurs de taux d\'humidité (3,36 et 8,3 %), d\'indices d\'acide (12,80 et 14,97 mgKOH/g) et de peroxyde (17,92 et 14,70 mEgO2/kg) différentes et plus faibles que celles du beurre de karité gris (14,50 %, 17,32 mgKOH/g, 30,88 mEgO2/kg, respectivement). Ces beurres du marchés renferment des métaux lourds comme le plomb et le nickel à des proportions variables de 91,60 à 4,84 mg/kg (plomb) et, 3,07 à 1,27 mg/kg (nickel), mais aussi de fortes charges de Coliformes totaux (2.10+2/g), les levures et moisissures (1.10+4/g) et quelque fois des Salmonella.Shea butters from Côte d'Ivoire's markets present a wide diversity depending on colour, odour and texture, nevertheless yellow (67.9 %) rancid (33.99 %) and hard (93.83 %) shea buttets are dominant. Physicochemical characteristics are different according to colour. Beige and yellow shea butters had lower moisture content (3.36 and 8.3 %), acidity (12.80 and 14.97 mgKOH/g) and peroxide (17.92 and 14.70 mEgO2/kg) respectively, than the grey (14.50 %, 17.32 mgKOH/g, 30.88 mEgO2/kg, respectively). These butters contain heavy metals such as lead (91.60 to 4.84 mg/kg) and nickel (3.07 to 1.27 mg/kg). They also have high loads of Coliforms (2.10+2/g ), yeast and moulds (1.10+4/g), and sometimes Salmonella Keywords: Beurre de karité, Vitellaria paradoxa, propriétés, Côte d'Ivoire.Agronomie Africaine Vol. 20 (2) 2008: pp. 221-23

    Constraints for the nuclear parton distributions from Z and W production at the LHC

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    The LHC is foreseen to finally bring also the nuclear collisions to the TeV scale thereby providing new possibilities for physics studies, in particular related to the electro-weak sector of the Standard Model. We study here the Z and W production in proton-lead and lead-lead collisions at the LHC, concentrating on the prospects of testing the factorization and constraining the nuclear modifications of the parton distribution functions (PDFs). Especially, we find that the rapidity asymmetries in proton-nucleus collisions, arising from the differences in the PDFs between the colliding objects, provide a decisive advantage in comparison to the rapidity-symmetric nucleus-nucleus case. We comment on how such studies will help to improve our knowledge of the nuclear PDFs.Comment: The version accepted for publication in JHEP. New figures has been added, and we also discuss the single charged lepton productio

    Task relevance modulates the behavioural and neural effects of sensory predictions

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    The brain is thought to generate internal predictions to optimize behaviour. However, it is unclear whether predictions signalling is an automatic brain function or depends on task demands. Here, we manipulated the spatial/temporal predictability of visual targets, and the relevance of spatial/temporal information provided by auditory cues. We used magnetoencephalography (MEG) to measure participants' brain activity during task performance. Task relevance modulated the influence of predictions on behaviour: spatial/temporal predictability improved spatial/temporal discrimination accuracy, but not vice versa. To explain these effects, we used behavioural responses to estimate subjective predictions under an ideal-observer model. Model-based time-series of predictions and prediction errors (PEs) were associated with dissociable neural responses: predictions correlated with cue-induced beta-band activity in auditory regions and alpha-band activity in visual regions, while stimulus-bound PEs correlated with gamma-band activity in posterior regions. Crucially, task relevance modulated these spectral correlates, suggesting that current goals influence PE and prediction signalling

    Fluoride levels in UK infant milks.

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    Aim To provide a comprehensive report of fluoride concentration in UK infant milks and estimate their contribution to daily fluoride intake. Methods A total of 60 formula milk products available commercially or within a hospital environment were analysed, along with eight pasteurised cow’s milk samples. Formula milk products requiring preparation were reconstituted with fresh Leeds tap water (0.02 ppmF). Fluoride concentration was measured for all products directly using an ion selective electrode after addition of low-level total ionic strength adjustment buffer. Results The overall median fluoride concentration for the 68 infant milks was 0.025 ppmF, with a wide range of 0.002–0.282 ppmF. Analysis revealed variation between composition and manufacturer, in addition to differences between measured and labeled fluoride concentration. Although all products contained low fluoride concentration, the fluoride concentrations for formula milks used within the hospital setting (0.029 ppmF) were statistically higher in comparison to the commercial formula milk (0.016 ppmF) and cow’s milk (0.017 ppmF) products. The daily fluoride contribution from infant milks was low; 0.0034 mgF/kg body weight per day was estimated between birth and 6 months of age, further decreasing as intake of infant milk decreased with age. Conclusions Fluoride concentration of the analysed infant milks is low, providing minimal contribution towards total daily F intake and alone are unlikely to pose a threat for the development of dental fluorosis

    Aggregation of Votes with Multiple Positions on Each Issue

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    We consider the problem of aggregating votes cast by a society on a fixed set of issues, where each member of the society may vote for one of several positions on each issue, but the combination of votes on the various issues is restricted to a set of feasible voting patterns. We require the aggregation to be supportive, i.e. for every issue jj the corresponding component fjf_j of every aggregator on every issue should satisfy fj(x1,,,xn){x1,,,xn}f_j(x_1, ,\ldots, x_n) \in \{x_1, ,\ldots, x_n\}. We prove that, in such a set-up, non-dictatorial aggregation of votes in a society of some size is possible if and only if either non-dictatorial aggregation is possible in a society of only two members or a ternary aggregator exists that either on every issue jj is a majority operation, i.e. the corresponding component satisfies fj(x,x,y)=fj(x,y,x)=fj(y,x,x)=x,x,yf_j(x,x,y) = f_j(x,y,x) = f_j(y,x,x) =x, \forall x,y, or on every issue is a minority operation, i.e. the corresponding component satisfies fj(x,x,y)=fj(x,y,x)=fj(y,x,x)=y,x,y.f_j(x,x,y) = f_j(x,y,x) = f_j(y,x,x) =y, \forall x,y. We then introduce a notion of uniformly non-dictatorial aggregator, which is defined to be an aggregator that on every issue, and when restricted to an arbitrary two-element subset of the votes for that issue, differs from all projection functions. We first give a characterization of sets of feasible voting patterns that admit a uniformly non-dictatorial aggregator. Then making use of Bulatov's dichotomy theorem for conservative constraint satisfaction problems, we connect social choice theory with combinatorial complexity by proving that if a set of feasible voting patterns XX has a uniformly non-dictatorial aggregator of some arity then the multi-sorted conservative constraint satisfaction problem on XX, in the sense introduced by Bulatov and Jeavons, with each issue representing a sort, is tractable; otherwise it is NP-complete
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