8,353 research outputs found
Current status of las tablas de daimiel national park wetland and actions required for conservation
Wetlands are complex ecosystems that play multiple roles. ‘Las Tablas de Daimiel National Park’ (TDNP) undoubtedly plays a role in several ecosystem services and provides a connection between nature, farmers, scientists, residents, and other stakeholders. The state of degradation and/or vulnerability of this ecosystem (with a series of socio-economic implications) have led the publication of numerous articles. The work reported here provides a description of the growing importance of this wetland within the rural landscapes of La Mancha and emphasizes its state of degradation, mainly since pedological point of view. In this way, particular attention is required to assure the conservation of the Tablas of Daimiel Wetland; thus, several measures are proposed to improve the conservation of this area as to control and prohibit any dumping of any type of waste in the park or in its vicinityThis Research was funded by Organismo Autonomo Parques Nacionales (Autonomous Organism National Parks) of Spain (OAPN
Genomic characterisation of an endometrial pathogenic <i>Escherichia coli</i> strain reveals the acquisition of genetic elements associated with extra-intestinal pathogenicity
<b>Background</b><p></p>
Strains of <i>Escherichia coli</i> cause a wide variety of intestinal and extra-intestinal diseases in both humans and animals, and are also often found in healthy individuals or the environment. Broadly, a strong phylogenetic relationship exists that distinguishes most <i>E. Coli</i> causing intestinal disease from those that cause extra-intestinal disease, however, isolates within a recently described subclass of Extra-Intestinal Pathogenic <i>E. Coli</i> (ExPEC), termed endometrial pathogenic <i>E. Coli</i>, tend to be phylogenetically distant from the vast majority of characterised ExPECs, and more closely related to human intestinal pathogens. In this work, we investigate the genetic basis for ExPEC infection in the prototypic endometrial pathogenic <i>E. Coli</i> strain MS499.<p></p>
<b>Results</b><p></p>
By investigating the genome of MS499 in comparison with a range of other E. coli sequences, we have discovered that this bacterium has acquired substantial lengths of DNA which encode factors more usually associated with ExPECs and less frequently found in the phylogroup relatives of MS499. Many of these acquired factors, including several iron acquisition systems and a virulence plasmid similar to that found in several ExPECs such as APEC O1 and the neonatal meningitis <i>E. Coli</i> S88, play characterised roles in a variety of typical ExPEC infections and appear to have been acquired recently by the evolutionary lineage leading to MS499.<p></p>
<b>Conclusions</b><p></p>
Taking advantage of the phylogenetic relationship we describe between MS499 and several other closely related <i>E. Coli</i> isolates from across the globe, we propose a step-wise evolution of a novel clade of sequence type 453 ExPECs within phylogroup B1, involving the recruitment of ExPEC virulence factors into the genome of an ancestrally non-extraintestinal <i>E. Coli</i>, which has repurposed this lineage with the capacity to cause extraintestinal disease. These data reveal the genetic components which may be involved in this phenotype switching, and argue that horizontal gene exchange may be a key factor in the emergence of novel lineages of ExPECs.<p></p>
The ribosomal protein RACK1 is required for microRNA function in both C. elegans and humans
Despite the importance of microRNAs (miRNAs) in gene regulation, it is unclear how the miRNA-Argonaute complex-or miRNA-induced silencing complex (miRISC)-can regulate the translation of their targets in such diverse ways. We demonstrate here a direct interaction between the miRISC and the ribosome by showing that a constituent of the eukaryotic 40S subunit, receptor for activated C-kinase (RACK1), is important for miRNA-mediated gene regulation in animals. In vivo studies demonstrate that RACK1 interacts with components of the miRISC in nematodes and mammals. In both systems, the alteration of RACK1 expression alters miRNA function and impairs the association of the miRNA complex with the translating ribosomes. Our data indicate that RACK1 can contribute to the recruitment of miRISC to the site of translation, and support a post-initiation mode of miRNA-mediated gene repression. © 2011 European Molecular Biology Organization
Creation of functional viruses from non-functional cDNA clones obtained from an RNA virus population by the use of ancestral reconstruction
RNA viruses have the highest known mutation rates. Consequently it is likely that a high proportion of individual RNA virus genomes, isolated from an infected host, will contain lethal mutations and be non-functional. This is problematic if the aim is to clone and investigate high-fitness, functional cDNAs and may also pose problems for sequence-based analysis of viral evolution. To address these challenges we have performed a study of the evolution of classical swine fever virus (CSFV) using deep sequencing and analysis of 84 full-length cDNA clones, each representing individual genomes from a moderately virulent isolate. In addition to here being used as a model for RNA viruses generally, CSFV has high socioeconomic importance and remains a threat to animal welfare and pig production. We find that the majority of the investigated genomes are non-functional and only 12% produced infectious RNA transcripts. Full length sequencing of cDNA clones and deep sequencing of the parental population identified substitutions important for the observed phenotypes. The investigated cDNA clones were furthermore used as the basis for inferring the sequence of functional viruses. Since each unique clone must necessarily be the descendant of a functional ancestor, we hypothesized that it should be possible to produce functional clones by reconstructing ancestral sequences. To test this we used phylogenetic methods to infer two ancestral sequences, which were then reconstructed as cDNA clones. Viruses rescued from the reconstructed cDNAs were tested in cell culture and pigs. Both reconstructed ancestral genomes proved functional, and displayed distinct phenotypes in vitro and in vivo. We suggest that reconstruction of ancestral viruses is a useful tool for experimental and computational investigations of virulence and viral evolution. Importantly, ancestral reconstruction can be done even on the basis of a set of sequences that all correspond to non-functional variants
Effectiveness and cost-effectiveness of a novel, group self-management course for adults with chronic musculoskeletal pain: study protocol for a multicentre, randomised controlled trial (COPERS)
Introduction: Chronic musculoskeletal pain is a
common condition that often responds poorly to
treatment. Self-management courses have been
advocated as a non-drug pain management
technique, although evidence for their effectiveness
is equivocal. We designed and piloted a
self-management course based on evidence for
effectiveness for specific course components and
characteristics.
Methods/analysis: COPERS (coping with persistent
pain, effectiveness research into self-management) is
a pragmatic randomised controlled trial testing the
effectiveness and cost-effectiveness of an intensive,
group, cognitive behavioural-based, theoretically
informed and manualised self-management course
for chronic pain patients against a control of best
usual care: a pain education booklet and a relaxation
CD. The course lasts for 15 h, spread over 3 days,
with a –2 h follow-up session 2 weeks later. We aim
to recruit 685 participants with chronic
musculoskeletal pain from primary, intermediate and
secondary care services in two UK regions. The
study is powered to show a standardised mean
difference of 0.3 in the primary outcome, pain-related
disability. Secondary outcomes include generic
health-related quality of life, healthcare utilisation,
pain self-efficacy, coping, depression, anxiety and
social engagement. Outcomes are measured at 6 and
12 months postrandomisation. Pain self-efficacy is
measured at 3 months to assess whether change
mediates clinical effect.
Ethics/dissemination: Ethics approval was given
by Cambridgeshire Ethics 11/EE/046. This trial will
provide robust data on the effectiveness and
cost-effectiveness of an evidence-based, group
self-management programme for chronic
musculoskeletal pain. The published outcomes will
help to inform future policy and practice around such
self-management courses, both nationally and
internationally.
Trial registration: ISRCTN24426731
Are the responses generated during a psychophysical task independent of previously presented stimuli or do they depend on earlier stimulus presentations?
Quinn and Watt (2006 Perception 35 267 - 280) showed that the optimal tempi for pieces of music (ie the appropriate speed for a melody) vary from melody to melody. The current study tested if such tempi responses depend on previous stimulus presentations. To do this, we ran a many-participants single-presentation version of the Quinn and Watt experiment. 616 visitors to the Glasgow Science Centre participated. We found that the results substantially matched those obtained earlier, and demonstrate that participants' responses are essentially independent of previously presented stimuli
Planar polymer waveguides with a graded-index profile resulting from intermixing of methacrylates in closed microchannels
Graded-index waveguides are known to exhibit lower losses and considerably larger bandwidths compared to step-index waveguides. The present work reports on a new concept for realizing such waveguides on a planar substrate by capillary filling microchannels (cladding) with monomer solution (core). A graded-index profile is obtained by intermi xing between the core and cladding material at the microchannel interface. To this end, various ratios of methyl methacrylate (MMA) and octafluoropentyl methacrylate (OFPMA) were evaluated as starting monomers and the results showed that the polymers P50:50 (50:50 MMA:OFPMA) and P0:100 (100% OFPMA) were suitable to be applied as waveguide core and cladding material respectively. Light guiding in the resulting P50:50/P0:100 waveguides was demonstrated and the refractive-index profile was quantified and compared with that of conventional step-index waveguides. The results for both cases were clearly different and a gradual refractive index transition between the core and cladding was found for the newly developed waveguides. Although the concept has been demonstrated in a research environment, it also has potential for upscaling by employing drop-on-demand dispensing of polymer waveguide material in pre-patterned microchannels, for example in a roll-to-roll environment
Prevalence and impact of chronic widespread pain in the Bangladeshi and White populations of Tower Hamlets, East London
The prevalence and impact of chronic pain differ between ethnic groups. We report a study of the comparative prevalence and impact of chronic pain in Bangladeshi, British Bangladeshi and White British/Irish people. We posted a short questionnaire to a random sample of 4,480 patients registered with 16 general practices in the London Borough of Tower Hamlets and conducted a longer questionnaire with patients in the waiting areas at those practices. We distinguished between Bangladeshi participants who were born in the UK or had arrived in the UK at the age of 14 or under (British Bangladeshi) and those who arrived in UK at the age of over 14 (Bangladeshi). We obtained 1,223/4,480 (27 %) responses to the short survey and 600/637 (94 %) to the long survey. From the former, the prevalence of chronic pain in the White, British Bangladeshi and Bangladeshi groups was 55, 54 and 72 %, respectively. The corresponding figures from the long survey were 49, 45 and 70 %. Chronic widespread pain was commoner in the Bangladeshi (16 %) than in the White (10 %) or British Bangladeshi (9 %) groups. People with chronic pain experienced poorer quality of life (odds ratio for scoring best possible health vs. good health (or good vs. poor health) 5.6 (95 % confidence interval 3.4 to 9.8)), but we found no evidence of differences between ethnic groups in the impact of chronic pain on the quality of life. Chronic pain is commoner and, of greater severity, in Bangladeshis than in Whites. On most measures in this study, British Bangladeshis resembled the Whites more than the Bangladeshis
Argamassas térmicas à base de cal
Actualmente, as preocupações com o consumo energético dos edifÃcios são cada
vez maiores. Surgindo desta forma, a necessidade de incorporação de materiais em produtos
de construção que visem a melhoria da eficiência energética dos edifÃcios. Portanto, a
utilização de materiais de mudança de fase surge como uma possÃvel solução para tentar
solucionar, ou pelo menos minimizar, os enormes consumos energéticos associados aos
edifÃcios. Este estudo visa o conhecimento da influência da incorporação de microcápsulas
de materiais de mudança de fase (PCM) em argamassas à base de cal, devendo estas possuir
um compromisso entre a trabalhabilidade, resistência mecânica e aparência estética
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