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1.
JMIR Med Educ ; 10: e48393, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38437007

RESUMO

BACKGROUND: Access to reliable and accurate digital health web-based resources is crucial. However, the lack of dedicated search engines for non-English languages, such as French, is a significant obstacle in this field. Thus, we developed and implemented a multilingual, multiterminology semantic search engine called Catalog and Index of Digital Health Teaching Resources (CIDHR). CIDHR is freely accessible to everyone, with a focus on French-speaking resources. CIDHR has been initiated to provide validated, high-quality content tailored to the specific needs of each user profile, be it students or professionals. OBJECTIVE: This study's primary aim in developing and implementing the CIDHR is to improve knowledge sharing and spreading in digital health and health informatics and expand the health-related educational community, primarily French speaking but also in other languages. We intend to support the continuous development of initial (ie, bachelor level), advanced (ie, master and doctoral levels), and continuing training (ie, professionals and postgraduate levels) in digital health for health and social work fields. The main objective is to describe the development and implementation of CIDHR. The hypothesis guiding this research is that controlled vocabularies dedicated to medical informatics and digital health, such as the Medical Informatics Multilingual Ontology (MIMO) and the concepts structuring the French National Referential on Digital Health (FNRDH), to index digital health teaching and learning resources, are effectively increasing the availability and accessibility of these resources to medical students and other health care professionals. METHODS: First, resource identification is processed by medical librarians from websites and scientific sources preselected and validated by domain experts and surveyed every week. Then, based on MIMO and FNRDH, the educational resources are indexed for each related knowledge domain. The same resources are also tagged with relevant academic and professional experience levels. Afterward, the indexed resources are shared with the digital health teaching and learning community. The last step consists of assessing CIDHR by obtaining informal feedback from users. RESULTS: Resource identification and evaluation processes were executed by a dedicated team of medical librarians, aiming to collect and curate an extensive collection of digital health teaching and learning resources. The resources that successfully passed the evaluation process were promptly included in CIDHR. These resources were diligently indexed (with MIMO and FNRDH) and tagged for the study field and degree level. By October 2023, a total of 371 indexed resources were available on a dedicated portal. CONCLUSIONS: CIDHR is a multilingual digital health education semantic search engine and platform that aims to increase the accessibility of educational resources to the broader health care-related community. It focuses on making resources "findable," "accessible," "interoperable," and "reusable" by using a one-stop shop portal approach. CIDHR has and will have an essential role in increasing digital health literacy.


Assuntos
Saúde Digital , Semântica , Humanos , Ferramenta de Busca , Idioma , Aprendizagem
2.
J Mol Evol ; 68(5): 461-74, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19357802

RESUMO

We studied the population genetics of two antimicrobial peptide (AMP) loci, called Mytilin B and Mytilus galloprovincialis defensin 2 (MGD2), in the secondary contact mosaic hybrid zone between Mytilus edulis and M. galloprovincialis. The isolation period between the two species was estimated to be approximately 1 million years (range, 0.5 million to 2 million years) long. During this period, coevolution between microbes and the immune system has likely occurred. The secondary contact, which would date back to approximately 25,000 (0-200,000) years, recently allowed these coadaptations to be rearranged through hybridization. Distinctive polymorphisms were uncovered in coding sequences of the two AMP loci such as insertion/deletion of codons or bisubstituted codons. Very low levels of differentiation were observed between populations of the two species at both loci, while other nuclear loci often showed marked structure among the same samples. The absence of population differentiation proved to be the consequence of secondary introgression of highly divergent alleles. While only a few recombinants were observed at the Mytilin B locus, the MGD2 locus showed a high intragenic recombination rate, which increased in the exon coding for the mature peptide. In addition, standard neutrality tests revealed significant deviations from the mutation-drift equilibrium at both loci. These results suggest that either balancing or directional selection is likely to play a role in the evolution of the two AMPs and introgression would be adaptive. However, evidence accumulated at the Mytilin B locus allows neither for identification of the direction of selection nor for any conclusions on whether selection acted directly on the antimicrobial peptide itself. At the MGD2 locus, a spatial variation of polymorphism patterns along the sequence suggests that selection was direct, although the precise nature of the selection (directional vs. balancing) remains unclear. This study concurs with previous reports of an effect of slight selection on AMP genes evolution in other invertebrates, although selection does not necessarily act on the mature peptides.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Fluxo Gênico , Mytilus edulis/genética , Mytilus/genética , Alelos , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Clonagem Molecular , Geografia , Desequilíbrio de Ligação/genética , Modelos Genéticos , Dados de Sequência Molecular , Nucleotídeos/genética , Filogenia , Polimorfismo Genético , Dinâmica Populacional , Sequências Repetitivas de Ácido Nucleico , Alinhamento de Sequência
3.
BMC Evol Biol ; 8: 164, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18513403

RESUMO

BACKGROUND: Few models of genetic hitchhiking in subdivided populations have been developed and the rarity of empirical examples is even more striking. We here provide evidences of genetic hitchhiking in a subdivided population of the marine mussel Mytilus edulis. In the Bay of Biscay (France), a patch of M. edulis populations happens to be separated from its North Sea conspecifics by a wide region occupied only by the sister species M. galloprovincialis. Although genetic differentiation between the two M. edulis regions is largely non-significant at ten marker loci (average FST~0.007), a strong genetic differentiation is observed at a single locus (FST = 0.25). We validated the outlier status of this locus, and analysed DNA sequence polymorphism in order to identify the nature of the selection responsible for the unusual differentiation. RESULTS: We first showed that introgression of M. galloprovincialis alleles was very weak in both populations and did not significantly affect their differentiation. Secondly, we observed the genetic signature of a selective sweep within both M. edulis populations in the form of a star-shaped clade of alleles. This clade was nearly fixed in the North Sea and was segregating at a moderate frequency in the Bay of Biscay, explaining their genetic differentiation. Incomplete fixation reveals that selection was not direct on the locus but that the studied sequence recombined with a positively selected allele at a linked locus while it was on its way to fixation. Finally, using a deterministic model we showed that the wave of advance of a favourable allele at a linked locus, when crossing a strong enough barrier to gene flow, generates a step in neutral allele frequencies comparable to the step observed between the two M. edulis populations at the outlier locus. In our case, the position of the barrier is now materialised by a large patch of heterospecific M. galloprovincialis populations. CONCLUSION: High FST outlier loci are usually interpreted as being the consequence of ongoing divergent local adaptation. Combining models and data we show that among-population differentiation can also dramatically increase following a selective sweep in a structured population. Our study illustrates how a striking geographical pattern of neutral diversity can emerge from past indirect hitchhiking selection in a structured population. NOTE: Nucleotide sequences reported in this paper are available in the GenBanktrade mark database under the accession numbers EU684165 - EU684228.


Assuntos
Modelos Genéticos , Mytilus edulis/genética , Animais , Oceano Atlântico , Fluxo Gênico , Frequência do Gene , Variação Genética , Genética Populacional , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , Seleção Genética
4.
Oecologia ; 145(3): 345-53, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16001221

RESUMO

The concept of niche overlap appears in studies of the mechanisms of the maintenance of species diversity, in searches for assembly rules, and in estimation of within-community species redundancy. For plant traits measured on a continuous scale, existing indices are inadequate because they split the scale into a number of categories thus losing information. An index is easy to construct if we assume a normal distribution for each trait within a species, but this assumption is rarely true. We extend and apply an index, NO(K), which is based on kernel density functions, and can therefore work with distributions of any shape without prior assumptions. For cases where the ecologist wishes to downweight traits that are inter-correlated, we offer a variant that does this: NO(Kw). From either of these indices, an index of the mean niche overlap in a community can be calculated: NO(K,community) and NO(Kw,community). For all these indices, the variance can be calculated and formulae for this are given. To give examples of the new indices in use, we apply them to a coastal fish dataset and a sand-dune plant dataset. The former exhibits considerable non-normality, emphasising the need for kernel-based indices. Accordingly, there was a considerable difference in index values, with those for an index based on a normal distribution being significantly higher than those from an index which, being based on kernel fitting, is not biased by an assumption for the distribution. The NO(K) values were ecologically consistent for the fish species concerned, varying from 0.02 to 0.53. The sand-dune plant data also showed a wide range of overlap values. Interestingly, the least overlap was between two graminoids, which would have been placed in the same functional group in the coarse classification often used in functional-type/ecosystem-function work.


Assuntos
Ecologia/métodos , Ecossistema , Meio Ambiente , Modelos Teóricos , Animais , Peixes/anatomia & histologia , Peixes/fisiologia , Fenômenos Fisiológicos Vegetais , Plantas/anatomia & histologia , Especificidade da Espécie
6.
Angew Chem Int Ed Engl ; 38(4): 518-522, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29711764

RESUMO

A 97% yield of [Ru3 (CO)12 ] (2) in 20 minutes is obtained simply by treating [Ru(CO)3 Cl2 (thf)] with KOH under CO (1 atm). The reduction to Ru0 can be explained in terms of the facile reductive elimination of HCl from the transient hydrido complex 1. Though elusive, the latter can be intercepted by olefins or alkynes to produce trappable alkyl or alkenyl complexes such as 3 and 4.█ denotes a vacant coordination site.

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