68 research outputs found
Pollinator preference in a hybrid zone between two generalist plant species
Dissertação de mestrado em Ecologia, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências da Universidade de Coimbra.The evolutionary mechanism behind flowers and its pollinators is generally understood to be a
gradual co-adaptive process where the plant specializes to its most efficient pollinator, which exerts
selective pressures on specific traits, driving floral evolution. Still, most flowering plants in nature are
visited by a wide array of pollinator species, i.e. are generalist plants. However, the role of pollinators as
significant drivers of floral evolution in generalist plants has been questioned due to the potential
conflicting selection regimes exerted by different pollinators. Taking this into account, using a
combination of observation and manipulative experiments, we assessed pollinator preference in a
natural contact zone where the generalist rayed species Anacyclus clavatus and the rayless A. valentinus
co-exist and hybridize, forming intermediate phenotypes. These contact areas show a remarkably high
phenotypic variation, with the intermediate phenotype bridging both phenotypes and forming an
exceptional micro-evolutive framework to explore how generalist pollinators could be driving the
evolution of floral phenotypes. We found that the production of rays influenced the probability of being
visited by specific insect groups, in particular by Dipteran groups; whereas bees showed no preference
for rayed phenotypes and their visitation patterns were mainly driven by the number of capitula
simultaneously blooming in the plant. In addition, we found support for the importance of the
neighbours’ phenotype when assessing pollinator preference on a focal individual. Rayed plants
benefited from having other conspicuous neighbours, whereas rayless and intermediate phenotypes
significantly competed for pollinators. In conclusion, all these differential behavioural patterns of floral
visitors might affect gene flow within the hybrid zone between A. clavatus and A. valentinus influencing
the degree of reproductive isolation and floral evolution between both species.Os mecanismos evolutivos que atuam nas flores e respetivos polinizadores são normalmente
descritos como processos de co-adaptação gradual onde a planta se especializa no seu polinizador mais
eficiente, que por sua vez, exerce pressões evolutivas em características específicas e dessa forma guia a
evolução da flor. Ainda assim, a maior parte das plantas com flor são polinizadas por um leque
diversificado de espécies de polinizadores, denominando-se assim plantas generalistas. No entanto, em
plantas generalistas o papel dos polinizadores na evolução floral tem sido questionado devido a
potenciais conflitos na selecção exercida pelas diferentes espécies de polinizadores que visitam a flor.
Tendo isto em conta, abordagens observacionais e manipulativas foram utilizadas para avaliar as
preferências dos polinizadores numa zona de contacto onde as espécies generalistas Anacyclus clavatus
(com lígulas) e a espécie A. valentinus (sem lígulas) coexistem e hibridizam, formando fenótipos
intermédios. Estas áreas possuem uma variação fenotípica notável, com o fenótipo intermédio a
representar o cruzamento entre as duas espécies, garantindo um cenário microevolutivo excecional para
estudar de que forma os polinizadores conduzem a evolução fenotípica em espécies generalistas. Os
resultados obtidos revelaram que a produção de lígulas influenciou a probabilidade das plantas serem
visitadas por grupos específicos de insetos, em particular por dípteros; por sua vez, as abelhas não
revelaram preferências por um fenótipo em particular, preferindo maioritariamente plantas com um
elevado número de capítulos em flor. Além disto, os nossos resultados evidenciaram também que a
composição fenotípica da vizinhança poderá desempenhar um papel importante na atração de uma
planta focal específica; em particular, plantas liguladas beneficiaram em ter outros vizinhos com lígulas,
enquanto que os fenótipos sem lígulas e intermédios competiram significativamente por polinizadores.
Os diferentes padrões de comportamento diferentes por parte dos visitantes florais observados neste
estudo podem afetar o fluxo genético na zona híbrida entre A. clavatus e A. valentinus, influenciando o
grau de isolamento reprodutivo e evolução floral entre as duas espécies
La regulación penal de la eutanasia. Análisis del art. 143.4 y estudio de Derecho Comparado
En el presente trabajo se hace una breve exposición sobre el concepto de eutanasia, así como los diferentes tipos que se distinguen. A continuación se realiza un análisis del artículo 143.4 del CP 1995 resaltando aquellos aspectos que han creado mayor controversia dentro de la doctrina junto con las opiniones de distintos autores. Por último se exponen las regulaciones sobre la eutanasia en Holanda y Francia, dos países con regulaciones muy diferentes entre sí, una más permisiva y otra más restrictiva, estableciendo las diferencias entre ambas y la regulación española
Sondas de ácido péptido nucleico, estojo e método para detectar espécies do género Lactobacillus spp. e/ou Gardnerella spp. e respectivas aplicações
O presente invento refere-se à concepção de duas sondas de
ácido péptido nucleíco (PNA) para detectar as bactérias
Lactobacillus e/ou Gardnerella spp.. Estas sondas são
aplicadas a um processo baseado em técnicas de biologia
molecular, nomeadamente de hibridação fluorescente in situ
(FISH), aplicáveis no diagnóstico de vaginose bacteriana ou
a detecção e quantificação destes géneros bacterianos em
diversos tipos de amostras, incluindo sangue, alimentos,
biopsias, fezes, água e outras amostras clínicas,
ambientais ou provenientes da indústria agrícola ou
alimentar
Dequalinium chloride effectively disrupts bacterial vaginosis (BV) Gardnerella spp. biofilms
Bacterial vaginosis (BV) is the most frequent vaginal infection worldwide. It is caused by the overgrowth of anaerobic vaginal pathogens such as Gardnerella spp. BV has been associated with the occurrence of dense multispecies biofilms on the vaginal mucosa. Treatment of biofilm-associated infections such as BV is challenging. In this study, we have tested the role of a quaternary ammonium compound, dequalinium chloride (DQC), in the eradication of Gardnerella spp. biofilms. The effects of the test substance on the biomass and the metabolic activity of the biofilm of Gardnerella spp. were assessed in vitro using a microtiter plate assay. In addition, the effect of DQC on the Gardnerella spp. biofilm was further assessed by using scanning electron microscopy and confocal laser scanning microscopy. The results showed that DQC was particularly effective in the destruction of BV-associated Gardnerella spp. biotypes, impacting both their biomass and metabolic activity. In addition, the disruption of biofilm architecture was evident and was probably caused by multiple mechanisms of action. We conclude that DQC is an antibiofilm agent and is able to efficiently destroy Gardnerella spp. BV-associated biofilms. Therefore, it is a valid option for BV therapy and has the potential to prevent BV recurrences.This work was supported by national funds from Fundação para a Ciência e Tecnologia (FCT), Portugal (Project UIDB/00709/2020), and by the European Regional Development Fund (ERDF), under the Portugal 2020 Program, through the Regional Operational Program of the Center (Centro2020), through the Project with the reference UIDB/00709/2020. C. Gaspar was supported by fellowship SFRH/BDE/112920/2015 from FCT; J. Rolo was supported by fellowship SFRH/BPD/115145/2016 from FCT. The human resources, consumables, and reagents, as well as publication charges, were partially funded by Medinova, Switzerland. All the results achieved are reported in this document (including negative results), and no member of Medinova interfered in
the experimental design or discussion of results.info:eu-repo/semantics/publishedVersio
Presence of Gardnerella vaginalis in healthy portuguese women: a pilot study
Bacterial vaginosis (BV) has an important position worldwide, as the leading vaginal disorder in women, and affects 30-50% of African women and 10-20% of White women of reproductive age. This condition although not mortal causes great discomfort and may lead to other complications such as pre-term labour or increase susceptibility for HIV infection.
During BV occur a decrease of Lactobacillus spp. present in the vaginal epithelium and an increase in the number of anaerobic microorganisms like Gardnerella vaginalis, Pretovella spp., Mobilincus spp.; Mycoplasma hominis and Atopobium vaginae. Gardnerella vaginalis is also responsible for the formation of a biofilm in the vaginal epithelium in sick women’s. However, the direct correlation between the pathology and the causing agent (or agents) has not been clearly established.
Currently there is only one article in PubMed (Guerreiro et. al, 1998) referring to the prevalence of bacterial vaginosis in Portugal and we aim to extend the research in this field specifically to the portuguese population. As part of this effort one of our aims it to characterise the bacterial population of portuguese women both healthy and diagnosed with BV. As such we collected swab samples of vaginal fluids from protuguese women with the help of health professionals and using self collection. The swabs were collected and treated within 24 hours at the University of Minho for the characterization of the bacterial population present, by using conventional microbiological growth techniques, PNA-FISH microscopy and 16S PCR.
It was found that about 20% of the samples tested possessed G. vaginalis and all possessed Lactobacillus spp. using all 3 identification techniques described. This result is consistent with previous reports of G. vaginalis prevalence althought slightly lower, and shows that traditional microbiological techniques, microscopy and molecular methods were consistent in terms of results
Biofilm formation of multidrug-resistant MRSA strains isolated from different types of human infections
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main pathogens causing chronic infections, mainly due to its capacity to form biofilms. However, the mechanisms underlying the biofilm formation of MRSA strains from different types of human infections are not fully understood. MRSA strains isolated from distinct human infections were characterized aiming to determine their biofilm-forming capacity, the biofilm resistance to conventional antibiotics and the prevalence of biofilm-related genes, including, icaA, icaB, icaC, icaD, fnbA, fnbB, clfA, clfB, cna, eno, ebpS, fib and bbp. Eighty-three clinical MRSA strains recovered from bacteremia episodes, osteomyelitis and diabetic foot ulcers were used. The biofilm-forming capacity was evaluated by the microtiter biofilm assay and the biofilm structure was analyzed via confocal scanning laser microscopy. The antimicrobial susceptibility of 24-h-old biofilms was assessed against three antibiotics and the biomass reduction was measured. The metabolic activity of biofilms was evaluated by the XTT assay. The presence of biofilm-related genes was investigated by whole-genome sequencing and by PCR. Despite different intensities, all strains showed the capacity to form biofilms. Most strains had also a large number of biofilm-related genes. However, strains isolated from osteomyelitis showed a lower capacity to form biofilms and also a lower prevalence of biofilm-associated genes. There was a significant reduction in the biofilm biomass of some strains tested against antibiotics. Our results provide important information on the biofilm-forming capacity of clinical MRSA strains, which may be essential to understand the influence of different types of infections on biofilm production and chronic infections.This work was funded by the R&D Project CAREBIO2: Comparative assessment of
antimicrobial resistance in environmental biofilms through proteomics—towards innovative thera-nostic biomarkers, with reference NORTE-01-0145-FEDER-030101 and PTDC/SAU-INF/30101/2017,
financed by the European Regional Development Fund (ERDF) through the Northern Regional
Operational Program (NORTE 2020) and the Foundation for Science and Technology (FCT). This
work was supported by the Associate Laboratory for Green Chemistry—LAQV which is financed
by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020). Vanessa Silva is
grateful to FCT (Fundação para a Ciência e a Tecnologia) for financial support through the PhD grant
SFRH/BD/137947/2018.info:eu-repo/semantics/publishedVersio
Gestión de las Tecnologías de la Información y Comunicación para mejorar el posicionamiento del SNIT en los rankings SIR y Webometrics
Para medir la producción científica y académica de las universidades se utilizan clasificaciones internacionales (rankings), que muestran el posicionamiento universitario a nivel internacional y regional, siendo un referente importante en la valoración del desempeño de las instituciones de educación superior.El Sistema Nacional de Institutos Tecnológicos (SNIT) cuenta con 262 instituciones de educación superior, de las cuales solo algunas tienen presencia individual en los rankings universitarios. El SNIT ha definido una estrategia-proyecto denominado “Presencia del Sistema Nacional de Institutos Tecnológicos en la Academia Mundial” cuyo propósito es mejorar el posicionamiento a través de la sumatoria de toda la producción científica y académica nacional.Las Tecnologías de la Información y Comunicación (TIC) son un pilar fundamental en todos los objetivos que se han planteado en este proyecto, TIC es un aliado estratégico en la visión de coadyuvar a que el SNIT sea una referencia mundial en educación superior.Palabra(s) Clave(s): Ranking, SNIT, TIC, SIR, Webometics
The Tetragnatha kauaiensis genome sheds light on the origins of genomic novelty in spider
Spiders (Araneae) have a diverse spectrum of morphologies, behaviors, and physiologies. Attempts to understand the genomic-basis of this diversity are often hindered by their large, heterozygous, and AT-rich genomes with high repeat content resulting in highly fragmented, poor-quality assemblies. As a result, the key attributes of spider genomes, including gene family evolution, repeat content, and gene function, remain poorly understood. Here, we used Illumina and Dovetail Chicago technologies to sequence the genome of the long-jawed spider Tetragnatha kauaiensis, producing an assembly distributed along 3,925 scaffolds with an N50 of ∼2 Mb. Using comparative genomics tools, we explore genome evolution across available spider assemblies. Our findings suggest that the previously reported and vast genome size variation in spiders is linked to the different representation and number of transposable elements. Using statistical tools to uncover gene-family level evolution, we find expansions associated with the sensory perception of taste, immunity, and metabolism. In addition, we report strikingly different histories of chemosensory, venom, and silk gene families, with the first two evolving much earlier, affected by the ancestral whole genome duplication in Arachnopulmonata (∼450 Ma) and exhibiting higher numbers. Together, our findings reveal that spider genomes are highly variable and that genomic novelty may have been driven by the burst of an ancient whole genome duplication, followed by gene family and transposable element expansion
PERSISTENCIA DE DATOS CON ActiveJDBC ORM
ResumenSe presenta un estudio realizado a ActiveJDBC un framework de persistencia de datos utilizado para el mapeo objeto-relacional (ORM) y aplicado en el lenguaje de programación Java. Se comienza con los fundamentos teóricos acerca de los ORM`s, se mencionan los principales ORM`s utilizados en Java, después se centra en el análisis y evaluación de ActiveJDBC a través de una aplicación de escritorio desarrollada para tal propósito. Esta aplicación se enlaza con una base de datos previamente creada y con miles de registros existentes para realizar pruebas de rendimiento del framework. Finalmente se muestran los resultados obtenidos como consecuencia de la aplicación de las pruebas y se comparan contra resultados obtenidos aplicando los métodos tradicionales de persistencia de datos como es JDBC.Palabras Clave: ActiveJDBC, hibernar, JDBC, ORM, persistencia. AbstractAn ActiveJDBC study is presented, it`s a data persistence framework for object-relational mapping (ORM) and implemented in the Java programming language. It begins with the theoretical foundations about ORM`s, the main ORM`s used in Java are mentioned, then it focuses on the analysis and evaluation of ActiveJDBC through a desktop application developed for this purpose. This application is linked to a database previously created with thousands of existing records for performance testing. Finally the results obtained as a result of the application of the tests are shown and compared against results obtained by applying traditional methods of data persistence as JDBC.Keywords: ActiveJDBC, hibernate, JDBC, ORM, persistence
Autenticación centralizada de los servicios digitales del ITC
En el artículo “Autenticación centralizada para los sistemas de información de los Institutos Tecnológicos y Dgest” publicado en el número 106 de esta revista, se planteó el problema de la autenticación de usuarios a nivel global dentro del sistema de Institutos Tecnológicos, y de cómo solucionar dicho problema en los sistemas de información ubicados en las Instituciones a nivel nacional. En este artículo se plantea una nueva solución que se puede implementar de manera local en las Instituciones, específicamente hablamos de los servicios digitales que ofrece hoy en día el Instituto Tecnológico de Celaya. Estos servicios incluye: Sistema Integral de Información, Red Inalámbrica Institucional, Sistemas de dosificación y Educación a distancia, así como cualquier otro sistema de información que se incorpore en un futuro a estos servicios.Palabra(s) Clave(s): Autenticación de usuarios, servicios digitales, radius, freeradius
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