2,055 research outputs found
Characterization of electrochemical systems using potential step voltammetry. Part II: Modeling of reversible systems
[EN] This study was carried out to compare the results obtained using potential step voltammetry and linear sweep voltammetry with a rotating gold disc electrode (RDE), when models based on equivalent circuits (EC) were used. The results lead to an equivalent circuit model that allows us to interpret the electrochemical behavior of aqueous solutions containing Fe(CN)(6)(-4) and Fe(CN)(6)(-3). With this model, we determined the values of the electrical resistance of the medium (R-s) as well as its polarization resistance (R-p), and established correlations between these values and the kinetic parameters of the system. The proposal highlights the need to introduce a new component for modeling using EC, which we have called the electrochemical diode. (C) 2019 Elsevier Ltd. All rights reserved.The authors gratefully acknowledge the financial support of BIA2016-78460-C3-3-R, MAT2015-64139-C4-3-R and RTI2018-100910-B-C43 (MINECO/FEDER) projects. We would also like to extend our appreciation for the pre-doctoral FPU scholarships (University Teacher Training scholarship) granted to Ana Martinez Ibernon (FPU 16/00723) and Jose Enrique Ramon Zamora (FPU13/00911) by the Spanish Ministry of Science and Innovation.MartĂnez-IbernĂłn, A.; RamĂłn Zamora, JE.; GandĂa-Romero, JM.; Gasch, I.; Valcuende PayĂĄ, MO.; AlcaĂąiz Fillol, M.; Soto Camino, J. (2019). Characterization of electrochemical systems using potential step voltammetry. Part II: Modeling of reversible systems. Electrochimica Acta. 328:1-10. https://doi.org/10.1016/j.electacta.2019.135111S11032
Improving phylogeny reconstruction at the strain level using peptidome datasets
Typical bacterial strain differentiation methods are often challenged by high genetic similarity between strains. To address this problem, we introduce a novel in silico peptide fingerprinting method based on conventional wet-lab protocols that enables the identification of potential strain-specific peptides. These can be further investigated using in vitro approaches, laying a foundation for the development of biomarker detection and application-specific methods. This novel method aims at reducing large amounts of comparative peptide data to binary matrices while maintaining a high phylogenetic resolution. The underlying case study concerns the Bacillus cereus group, namely the differentiation of Bacillus thuringiensis, Bacillus anthracis and Bacillus cereus strains. Results show that trees based on cytoplasmic and extracellular peptidomes are only marginally in conflict with those based on whole proteomes, as inferred by the established Genome-BLAST Distance Phylogeny (GBDP) method. Hence, these results indicate that the two approaches can most likely be used complementarily even in other organismal groups. The obtained results confirm previous reports about the misclassification of many strains within the B. cereus group. Moreover, our method was able to separate the B. anthracis strains with high resolution, similarly to the GBDP results as benchmarked via Bayesian inference and both Maximum Likelihood and Maximum Parsimony. In addition to the presented phylogenomic applications, whole-peptide fingerprinting might also become a valuable complementary technique to digital DNA-DNA hybridization, notably for bacterial classification at the species and subspecies level in the future.This research was funded by Grant AGL2013-44039-R from the Spanish âPlan Estatal de I+D+Iâ, and by Grant EM2014/046 from the âPlan Galego de investigaciĂłn, innovaciĂłn e crecemento 2011-2015â. BS was recipient of a RamĂłn y Cajal postdoctoral contractfrom the Spanish Ministry of Economyand Competitiveness. This work was also partially funded by the [14VI05] Contract-Programme from the University of Vigo and the Agrupamento INBIOMED from DXPCTSUG-FEDER unha maneira de facer Europa (2012/273).The research leading to these results has also received funding from the European Unionâs Seventh Framework Programme FP7/REGPOT-2012-2013.1 under grant agreement nË 316265, BIOCAPS. This document reflects only the authorsâ views and the European Union is not liable for any use that may be made of the information contained herein. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Titrimetric determination of zirconium
A brief literature survey on the present gravimetric, colorimetric, spectrographic, and volumetric methods for the determination of zirconium has been presented
Recommended from our members
Results of the ontology alignment evaluation initiative 2017
Ontology matching consists of finding correspondences between semantically related entities of different ontologies. The Ontology Alignment Evaluation Initiative (OAEI) aims at comparing ontology matching systems on precisely defined test cases. These test cases can be based on ontologies of different levels of complexity (from simple thesauri to expressive OWL ontologies) and use different evaluation modalities (e.g., blind evaluation, open evaluation, or consensus). The OAEI 2017 campaign offered 9 tracks with 23 test cases, and was attended by 21 participants. This paper is an overall presentation of that campaign
Competing values in public management
The main objective of the article is to review relevant literature on (competing) public values in public management and to present a number of perspectives on how to deal with value conflicts in different administrative settings and contexts. We start this symposium with the assumption that value conflicts are prevalent, the public context can be characterized by value pluralism, and instrumental rationality does not seem to be the most useful to understand or improve value conflicts in public governance. This begs the question: what is the best way to study and manage value conflicts? The contributions to this symposium issue approach value conflicts in public governance from different perspectives, within different countries and different administrative and management systems, hoping to contribute to the debate on how to deal with important yet conflicting public values in public management, without pretending to offer a conclusive strategy or approach. This introductory article also presents and reviews the contributions to this symposium issue. Š 2011 Taylor & Francis
How is the New Public Management applied in the occupational health care system? - decision-makers' and OH personnel's views in Finland
<p>Abstract</p> <p>Background</p> <p>In many countries occupational health care system is in change. Occupational health studies are mainly focused on occupational health substance and content. This study offers new perspectives on municipal OHS and its operations from management perspective.</p> <p>Aim</p> <p>The aim of this study is to analyse how New Public Management (NPM) doctrines are applied in the Finnish occupational health care system (OHS). The main focus is to describe and compare the views of decision-makers' and OH workers within the framework of NPM.</p> <p>Methods</p> <p>The data were collected by semi-structured interviews from 17 municipal decision-makers' and 26 municipal OH workers. Data was analyzed by examining coded data in a theory-driven way according to Hood's doctrine of NPM.</p> <p>Results</p> <p>The doctrines were not as compatible with the OH personnel view as with the decision-makers' view. Decision-makers and OH personnel highlighted the strict criteria required for operation evaluation. Moreover, decision-makers strongly accentuated professional management in the public sector and the reorganization of public sector units. These were not equally relevant in OH personnel views. In OH personnel views, other doctrines (more attention to performance and accomplishments, emphasizing and augmentation of the competition and better control of public expense and means test) were not similarly in evidence, only weak evidence was observed when their importance viewed as medium by decision-makers. Neither of the respondents group kept the doctrine of management models of the private sector relevant.</p> <p>Conclusions</p> <p>The NPM and Hoods doctrine fitted well with OH research. The doctrine brought out view differences and similarities between decision-makers and OH personnel. For example, policymakers highlighted more strongly the structural change by emphasizing professional management compared to OH personnel. The need for reorganization of municipal OH, regardless of different operational preconditions, was obvious for both decision-makers and OH personnel. The adaptation of more clarify management to a municipal context is not trouble-free. The municipality systemic structure, complex operational environment, and reconciliation of political and officer authority set challenges to management of municipalities.</p
The concept of "compartment allergy": prilocaine injected into different skin layers
We herein present a patient with delayed-type allergic hypersensitivity against prilocaine leading to spreading eczematous dermatitis after subcutaneous injections for local anesthesia with prilocaine. Prilocaine allergy was proven by positive skin testing and subcutaneous provocation, whereas the evaluation of other local anesthetics - among them lidocaine, articaine and mepivacaine - did not exhibit any evidence for cross-reactivity
Codivergence of Mycoviruses with Their Hosts
BACKGROUND: The associations between pathogens and their hosts are complex and can result from any combination of evolutionary events such as codivergence, switching, and duplication of the pathogen. Mycoviruses are RNA viruses which infect fungi and for which natural vectors are so far unknown. Thus, lateral transfer might be improbable and codivergence their dominant mode of evolution. Accordingly, mycoviruses are a suitable target for statistical tests of virus-host codivergence, but inference of mycovirus phylogenies might be difficult because of low sequence similarity even within families. METHODOLOGY: We analyzed here the evolutionary dynamics of all mycovirus families by comparing virus and host phylogenies. Additionally, we assessed the sensitivity of the co-phylogenetic tests to the settings for inferring virus trees from their genome sequences and approximate, taxonomy-based host trees. CONCLUSIONS: While sequence alignment filtering modes affected branch support, the overall results of the co-phylogenetic tests were significantly influenced only by the number of viruses sampled per family. The trees of the two largest families, Partitiviridae and Totiviridae, were significantly more similar to those of their hosts than expected by chance, and most individual host-virus links had a significant positive impact on the global fit, indicating that codivergence is the dominant mode of virus diversification. However, in this regard mycoviruses did not differ from closely related viruses sampled from non-fungus hosts. The remaining virus families were either dominated by other evolutionary modes or lacked an apparent overall pattern. As this negative result might be caused by insufficient taxon sampling, the most parsimonious hypothesis still is that host-parasite evolution is basically the same in all mycovirus families. This is the first study of mycovirus-host codivergence, and the results shed light not only on how mycovirus biology affects their co-phylogenetic relationships, but also on their presumable host range itself
- âŚ