Purpose Systematic reviews of patient-reported outcome measures (PROMs) differ from reviews of interventions and diagnostic test accuracy studies and are complex. In fact, conducting a review of one ...or more PROMs comprises of multiple reviews (i.e., one review for each measurement property of each PROM). In the absence of guidance specifically designed for reviews on measurement properties, our aim was to develop a guideline for conducting systematic reviews of PROMs. Methods Based on literature reviews and expert opinions, and in concordance with existing guidelines, the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) steering committee developed a guideline for systematic reviews of PROMs. Results A consecutive ten-step procedure for conducting a systematic review of PROMs is proposed. Steps 1-4 concern preparing and performing the literature search, and selecting relevant studies. Steps 5-8 concern the evaluation of the quality of the eligible studies, the measurement properties, and the interpretability and feasibility aspects. Steps 9 and 10 concern formulating recommendations and reporting the systematic review. Conclusions The COSMIN guideline for systematic reviews of PROMs includes methodology to combine the methodological quality of studies on measurement properties with the quality of the PROM itself (i.e., its measurement properties). This enables reviewers to draw transparent conclusions and making evidence-based recommendations on the quality of PROMs, and supports the evidence-based selection of PROMs for use in research and in clinical practice.
This work describes the first example of using chiral catalysts to control site-selectivity for the glycosylations of complex polyols such as 6-deoxyerythronolide B and oleandomycin-derived ...macrolactones. The regiodivergent introduction of sugars at the C3, C5, and C11 positions of macrolactones was achieved by selecting appropriate chiral acids as catalysts or through introduction of stoichiometric boronic acid-based additives. BINOL-based chiral phosphoric acids (CPAs) were used to catalyze highly selective glycosylations at the C5 positions of macrolactones (up to 99:1 rr), whereas the use of SPINOL-based CPAs resulted in selectivity switch and glycosylation of the C3 alcohol (up to 91:9 rr). Additionally, the C11 position of macrolactones was selectively functionalized through traceless protection of the C3/C5 diol with boronic acids prior to glycosylation. Investigation of the reaction mechanism for the CPA-controlled glycosylations revealed the involvement of covalently linked anomeric phosphates rather than oxocarbenium ion pairs as the reactive intermediates.
In this letter, a magnetically controlled single-stage ac-dc converter is proposed for low-power application which has the following features. First, single-stage operation is achieved by sharing ...switches between LLC resonant converter and totem-pole bridgeless power factor corrector (PFC) converter. Second, the power factor correction function is inherently achieved by designing the PFC converter to operate in discontinuous conduction mode. Third, the dc-link voltage is almost constant. Fourth, fixed switching frequency and duty cycle can be implemented for the switches, which simplifies the magnetic component and driver circuit design. Fifth, the LLC resonant converter is designed to operate at series resonant frequency, the highest efficiency operating point, so the converter can always achieve the maximum efficiency operation. Meanwhile, at this operating point, the converter output voltage is independent of the load so that it is functioning as a dc transformer; and finally, soft switching for all semiconductors is achieved. A 75-W experimental prototype is built to validate the proposed magnetically controlled single-stage ac-dc converter
Much of the deterioration of water resources is anthropogenically caused as a consequence of the incessant production of chemical compounds to obtain the quality of life that society demands today. ...This constant presence and harmful accumulation of these pollutants in different ecosystems have seen them emerge as a major concern both for human health and for environmental safety. Scientific advances have succeeded in legislating against, reducing and even eliminating priority pollutants, while new technologies are being constantly developed to identify and treat newly emerging pollutants. The objective of this work is the evaluation of the seawater reverse osmosis membrane as a method for the removal of an antibiotic present in seawater. The novelty of the study is that the tests were undertaken using water of high ionic strength. A critical selection of the antibiotic to be used in the study was carried out. The experiments were performed under constant pressure conditions, employing synthetic seawater in a pilot-scale unit with a commercial spiral-wound reverse osmosis membrane. Results are shown in terms of selectivity of the reverse osmosis process for antibiotic removal. The RO membrane element successfully reject most of the ciprofloxacin (removal rate >90%), with maximum rejection value of 99.96%.
•Evaluation of the membrane technology behavior for the emerging pollutants removal.•A laboratory-scale methodological sequence has been generated.•Reverse osmosis is able to eliminate ciprofloxacin by 99.96%.
A
bstract
The origin of the matter-antimatter asymmetry in the Universe is a fundamental question of physics. Electroweak baryogenesis is a compelling scenario for explaining it but it requires ...beyond the Standard Model sources of the CP symmetry violation. The simplest possibility is CP violation in the third generation fermion Higgs couplings, widely investigated theoretically and searched for experimentally. It has been found that the experimental bounds on the CP violation in the quark Yukawa couplings exclude their significant role in the electroweak baryogenesis, but it can be still played by the
τ
lepton Yukawa coupling. It is shown in this paper that, within the context of the Standard Model Effective Field Theory and assuming an underlying flavour symmetry of the Wilson coefficients, the electron dipole moment bound on the
τ
lepton Yukawa coupling is two orders of magnitude stronger than previously reported. This sheds strong doubts on its role in the electroweak baryogenesis, further stimulates the interest in its experimental verification and makes electroweak baryogenesis even more difficult to explain.
There is an increased interest on the identification, production, purification, evaluation and commercialization of new prebiotics with improved properties. Partial hydrolysis of pectin by chemical ...and/or enzymatic methods leads to the production of pectin-derived oligosaccharides (POS), which have been proposed as a new class of prebiotics. This work reviews the scientific information available on the production, chemical characterization, purification and properties of POS, with special focus on their in vitro and in vivo effects.
► Pectic oligosaccharides (POS) have been proposed as a new class of prebiotics. ► There are sound scientific evidences of the biological activity of POS. ► Additional studies are needed on the structure-function interrelationship. ► Fermentation studies in artificial colon and in vivo assays should be carried out. ► This work provides an updated overview on POS production and their properties.
Lipid-based nanocarriers for oral peptide delivery Niu, Zhigao; Conejos-Sánchez, Inmaculada; Griffin, Brendan T. ...
Advanced drug delivery reviews,
11/2016, Letnik:
106, Številka:
Pt B
Journal Article
Recenzirano
This article is aimed to overview the lipid-based nanostructures designed so far for the oral administration of peptides and proteins, and to analyze the influence of their composition and ...physicochemical (particle size, zeta potential) and pharmaceutical (drug loading and release) properties, on their interaction with the gastro-intestinal environment, and the subsequent PK/PD profile of the associated drugs. The ultimate goal has been to highlight and comparatively analyze the key factors that may be determinant of the success of these nanocarriers for oral peptide delivery. The article ends with some prospects on the challenges to be addressed for the intended commercial success of these delivery vehicles.
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Simulation studies suggest that pooled on-demand services (also referred to as Demand Responsive Transport, ridesharing, shared ride-hailing or shared ridesourcing services) have the potential to ...bring large benefits to urban areas while inducing limited time losses for their users. However, in reality, the large majority of users request individual rides (and not pooled rides) in existing on-demand services, leading to increases in motorised vehicle miles travelled. In this study, we investigate to what extent fare discounts, additional travel time, and the (un)willingness to share the ride with (different numbers of) other passengers play a role in the decision of individuals to share rides. To this end, we design a stated preference study targeting Dutch urban individuals. In our research, we (1) disentangle the sharing aspect from related time–cost trade-offs (e.g. detours), (2) investigate preference heterogeneity regarding the studied attributes and identify distinct market segments, and (3) simulate scenarios to understand the impact of the obtained parameters in the breakdown between individual and pooled services. We find that less than one third of respondents have strong preferences against sharing their rides. Also, we find that different market segments vary not only in their values of the willingness to share, but also in how they perceive this willingness to share (per-ride or proportional to the in-vehicle time). Further, the scenario analysis demonstrates that the share of individuals who are willing to share rides depends primarily on the time–cost trade-offs, rather than on the disutility stemming from pooling rides per se.
Rotation Forest: A New Classifier Ensemble Method Rodriguez, J.J.; Kuncheva, L.I.; Alonso, C.J.
IEEE transactions on pattern analysis and machine intelligence,
10/2006, Letnik:
28, Številka:
10
Journal Article
Recenzirano
We propose a method for generating classifier ensembles based on feature extraction. To create the training data for a base classifier, the feature set is randomly split into K subsets (K is a ...parameter of the algorithm) and principal component analysis (PCA) is applied to each subset. All principal components are retained in order to preserve the variability information in the data. Thus, K axis rotations take place to form the new features for a base classifier. The idea of the rotation approach is to encourage simultaneously individual accuracy and diversity within the ensemble. Diversity is promoted through the feature extraction for each base classifier. Decision trees were chosen here because they are sensitive to rotation of the feature axes, hence the name "forest". Accuracy is sought by keeping all principal components and also using the whole data set to train each base classifier. Using WEKA, we examined the rotation forest ensemble on a random selection of 33 benchmark data sets from the UCI repository and compared it with bagging, AdaBoost, and random forest. The results were favorable to rotation forest and prompted an investigation into diversity-accuracy landscape of the ensemble models. Diversity-error diagrams revealed that rotation forest ensembles construct individual classifiers which are more accurate than these in AdaBoost and random forest, and more diverse than these in bagging, sometimes more accurate as well
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