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This study examines the effect of changing the floor from a 2-mm homogenous vinyl floor to a 4-mm heterogeneous vinyl floor (1.5-mm wear layer and 2.5-mm foam layer) on musculoskeletal symptoms in the lower extremities and low back among nursing assistants in a geriatric care centre. A pre-post design with a reference group consisting of nursing assistants from a similar geriatric care centre was used. Follow-up measurements were carried out 12 and 24 months after the intervention by means of questionnaires. At the 1-year follow-up, the pain intensity score in the feet of the intervention group had decreased compared with the baseline value and remained statistically significant at the 2-year follow-up. The decrease in pain intensity score of the feet in the intervention group was statistically significantly different from the reference group, both after 1 and 2 years. PRACTITIONER SUMMARY: The results show the importance of flooring in the workplace with regard to reducing musculoskeletal symptoms. Appropriate flooring is especially important in the female-dominated health care sector, where workers must stand or walk for long periods.  相似文献   
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Current magnetic resonance imaging (MRI) technology allows the determination of patient-individual coronary tree structure, detection of infarctions, and assessment of myocardial perfusion. Joint inspection of these three aspects yields valuable information for therapy planning, e.g., through classification of myocardium into healthy tissue, regions showing a reversible hypoperfusion, and infarction with additional information on the corresponding supplying artery. Standard imaging protocols normally provide image data with different orientations, resolutions and coverages for each of the three aspects, which makes a direct comparison of analysis results difficult. The purpose of this work is to develop methods for the alignment and combined analysis of these images. The proposed approach is applied to 21 datasets of healthy and diseased patients from the clinical routine. The evaluation shows that, despite limitations due to typical MRI artifacts, combined inspection is feasible and can yield clinically useful information.  相似文献   
4.
In electrical impedance tomography (EIT) electric currents are injected into a body with unknown electromagnetic properties through a set of contact electrodes at the boundary of the body. The resulting voltages are measured on the same electrodes and the objective is to reconstruct the unknown conductivity function inside the body based on these data. All the traditional approaches to the reconstruction problem assume that the boundary of the body and the electrode-skin contact impedances are known a priori. However, in clinical experiments one usually lacks the exact knowledge of the boundary and contact impedances, and therefore, approximate model domain and contact impedances have to be used in the image reconstruction. However, it has been noticed that even small errors in the shape of the computation domain or contact impedances can cause large systematic artefacts in the reconstructed images, leading to loss of diagnostically relevant information. In a recent paper (Kolehmainen , 2006), we showed how in the 2-D case the errors induced by the inaccurately known boundary can be eliminated as part of the image reconstruction and introduced a novel method for finding a deformed image of the original isotropic conductivity using the theory of TeichmÜller mappings. In this paper, the theory and reconstruction method are extended to include the estimation of unknown contact impedances. The method is implemented numerically and tested with experimental EIT data. The results show that the systematic errors caused by inaccurately known boundary and contact impedances can efficiently be eliminated by the reconstruction method.   相似文献   
5.
Genetic fine mapping can be performed by exploiting the notion that haplotypes that are structurally similar in the neighbourhood of a disease predisposing locus are more likely to harbour the same susceptibility allele. Within the framework of Generalized Linear Mixed Models this can be formalized using spatial smoothing models, i.e. inducing a covariance structure for the haplotype risk parameters, such that risks associated with structurally similar haplotypes are dependent. In a Bayesian procedure a local similarity measure is calculated for each update of the presumed disease locus. Thus, the disease locus is searched as the place where the similarity structure produces risk parameters that can best discriminate between cases and controls.From a population genetic perspective the use of an identity-by-descent based similarity metric is theoretically motivated. This approach is then compared to other more intuitively motivated models and other similarity measures based on identity-by-state, suggested in the literature.  相似文献   
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Nipah virus is one of the most harmful emerging viruses with deadly effects on both humans and animals. Because of the severe outbreaks, in 2018, the World Health Organization focused on the urgent need for the development of effective solutions against the virus. However, up to date, there is no effective vaccine against the Nipah virus in the market. In the current study, the complete proteome of the Nipah virus (nine proteins) was analyzed for the antigenicity score and the virulence role of each protein, where we came up with fusion glycoprotein (F), glycoprotein (G), protein (V), and protein (W) as the candidates for epitope prediction. Following that, the multitope vaccine was designed based on top-ranking CTL, HTL, and BCL epitopes from the selected proteins. We used suitable linkers, adjuvant, and PADRE peptides to finalize the constructed vaccine, which was analyzed for its physicochemical features, antigenicity, toxicity, allergenicity, and solubility. The designed vaccine passed these assessments through computational analysis and, as a final step, we ran a docking analysis between the designed vaccine and TLR-3 and validated the docked complex through molecular dynamics simulation, which estimated a strong binding and supported the nomination of the designed vaccine as a putative solution for Nipah virus. Here, we describe the computational approach for design and analysis of this vaccine.  相似文献   
7.
Kraft black liquor lignin is a biofuel that is separated from the cellulose during kraft pulping. Improved technology and energy integration in paper mills have led to an energy surplus at many mills. It is therefore of great interest to extract the lignin from the pulp mill and sell it as fuel to replace fossil fuel in other furnaces. The fractionation of kraft black liquor with a total dry matter content of about 15 wt% has been studied using ultrafiltration. The flux for three polymeric membranes with different cut-offs was investigated as well as their retention of lignin and other process specific substances. The retention of lignin for the three membranes with cut-offs of 4,8 and 20 kDa was 80%, 67% and 45%, respectively. The retention of sulphur and sodium was zero for all three membranes. The purity of the final lignin fuel is of importances as the ash content preferably should be as low as possible. The flux and retention during concentration and diafiltration of the black liquor were therefore studied. The dialfiltration operation was conducted in batch and semicontinuous mode. The lignin purity was 36% in the original kraft black liquor and 78% after semi-continuous dialfiltration.  相似文献   
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Gaullier JM  Berven G  Blankson H  Gudmundsen O 《Lipids》2002,37(11):1019-1025
CLA mixtures are now commercially available. They differ from each other with respect to their content of CLA isomers and their degree of purification. As a group of natural FA, CLA have been widely assumed to be safe. However, the suspected presence of both impurities and particular isomers might induce undesirable side effects. Despite this potential health risk, only a few CLA preparations have been tested under rigorous conditions for clinical efficacy and safety. Based on the limited results available, it is possible to suggest that preparations enriched in c9,t11 and t10,c12 isomers are preferable for human consumption compared to preparations containing four isomers, in terms both of safety and efficacy.  相似文献   
10.
Microbial fuel cells (MFCs) produce electricity as a result of the microbial metabolism of organic substrates, hence they represent a sustainable approach for energy production and waste treatment. If the technology is to be implemented in industry, low cost and sustainable bioelectrodes must be developed to increase power output, increase waste treatment capacity, and improve service intervals. Although the current application of abiotic electrode catalysts, such as platinum and electrode binders such as Nafion leads to greater MFC performance, their use is cost prohibitive. Novel bioelectrodes which use cost effective and sustainable materials are being developed. These electrodes are developed with the intention to reduce start-up time, reduce costs, extend life-span and improve core MFC performance metrics (i.e. power density, current density, chemical oxygen demand (COD) reduction and Coulombic efficiency (CE)). Comparison of different MFC systems is not an easy task. This is due to variations in MFC design, construction, operation, and different inocula (in the case of mixed-culture MFCs). This high intra-system variability should be considered when assessing MFC data, operation and performance. This review article examines the major issues surrounding bioanode and biocathode improvement in different MFC systems, with the ultimate goal of streamlining and standardising improvement processes. © 2018 Society of Chemical Industry  相似文献   
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