32 research outputs found

    Phytoplankton dynamics in relation to seasonal variability and upwelling and relaxation patterns at the mouth of Ria de Aveiro (West Iberian Margin) over a four-year period

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    From June 2004 to December 2007, samples were weekly collected at a fixed station located at the mouth of Ria de Aveiro (West Iberian Margin). We examined the seasonal and inter-annual fluctuations in composition and community structure of the phytoplankton in relation to the main environmental drivers and assessed the influence of the oceano-graphic regime, namely changes in frequency and intensity of upwelling events, over the dynamics of the phytoplankton assemblage. The samples were consistently handled and a final subset of 136 OTUs (taxa with relative abundance > 0.01%) was subsequently submitted to various multivariate analyses. The phytoplankton assemblage showed significant changes at all temporal scales but with an overriding importance of seasonality over longer-(inter-annual) or shorter-term fluctuations (upwelling-related). Sea-surface temperature, salinity and maximum upwelling index were retrieved as the main driver of seasonal change. Seasonal signal was most evident in the fluctuations of chlorophyll a concentration and in the high turnover from the winter to spring phytoplankton assemblage. The seasonal cycle of production and succession was disturbed by upwelling events known to disrupt thermal stratification and induce changes in the phytoplankton assemblage. Our results indicate that both the frequency and intensity of physical forcing were important drivers of such variability, but the outcome in terms of species composition was highly dependent on the available local pool of species and the timing of those events in relation to the seasonal cycle. We conclude that duration, frequency and intensity of upwelling events, which vary seasonally and inter-annually, are paramount for maintaining long-term phytoplankton diversity likely by allowing unstable coexistence and incorporating species turnover at different scales. Our results contribute to the understanding of the complex mechanisms of coastal phytoplankton dynamics in relation to changing physical forcing which is fundamental to improve predictability of future prospects under climate change.Portuguese Foundation for Science and Technology (FCT, Portugal) [SFRH/BPD/ 94562/2013]; FEDER funds; national funds; CESAM [UID/AMB/50017]; FCT/MEC through national funds; FEDERinfo:eu-repo/semantics/publishedVersio

    Aromatherapy and nursing: historical and theoretical conception

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    Abstract Aromatherapy is a Practical or Complementary Health Therapy that uses volatile concentrates extracted from plants called essential oils, in order to improve physical, mental and emotional well-being. Aromatherapy has been practiced historically and worldwide by nurses and, as in Brazil is supported by the Federal Nursing Council, it is relevant to discuss this practice in the context of Nursing through Theories of Nursing. This study of theoretical reflection, exploratory and descriptive, aims to discuss the pharmacognosy of essential oils, the historical trajectory of Aromatherapy in Nursing and the conceptions to support Aromatherapy in light of eight Nursing Theorists (Florence Nightingale, Myra Levine, Hildegard Peplau, Martha Rogers, Callista Roy, Wanda Horta, Jean Watson and Katharine Kolcaba), contributing to its inclusion as a nursing care practice

    The third international stroke trial (IST-3) of thrombolysis for acute ischaemic stroke

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    <p>Abstract</p> <p>Background</p> <p>Intravenous recombinant tissue plasminogen activator (rt-PA) is approved for use in selected patients with ischaemic stroke within 3 hours of symptom onset. IST-3 seeks to determine whether a wider range of patients may benefit.</p> <p>Design</p> <p>International, multi-centre, prospective, randomized, open, blinded endpoint (PROBE) trial of intravenous rt-PA in acute ischaemic stroke. Suitable patients must be assessed and able to start treatment within 6 hours of developing symptoms, and brain imaging must have excluded intracerebral haemorrhage. With 1000 patients, the trial can detect a 7% absolute difference in the primary outcome. With3500 patients, it can detect a 4.0% absolute benefit & with 6000, (mostly treated between 3 & 6 hours), it can detect a 3% benefit.</p> <p>Trial procedures</p> <p>Patients are entered into the trial by telephoning a fast, secure computerised central randomisation system or via a secure web interface. Repeat brain imaging must be performed at 24–48 hours. The scans are reviewed 'blind' by expert readers. The primary measure of outcome is the proportion of patients alive and independent (Modified Rankin 0–2) at six months (assessed via a postal questionnaire mailed directly to the patient). Secondary outcomes include: events within 7 days (death, recurrent stroke, symptomatic intracranial haemorrhage), outcome at six months (death, functional status, EuroQol).</p> <p>Trial registration</p> <p>ISRCTN25765518</p

    Investigation of hospital discharge cases and SARS-CoV-2 introduction into Lothian care homes

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    Background The first epidemic wave of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Scotland resulted in high case numbers and mortality in care homes. In Lothian, over one-third of care homes reported an outbreak, while there was limited testing of hospital patients discharged to care homes. Aim To investigate patients discharged from hospitals as a source of SARS-CoV-2 introduction into care homes during the first epidemic wave. Methods A clinical review was performed for all patients discharges from hospitals to care homes from 1st March 2020 to 31st May 2020. Episodes were ruled out based on coronavirus disease 2019 (COVID-19) test history, clinical assessment at discharge, whole-genome sequencing (WGS) data and an infectious period of 14 days. Clinical samples were processed for WGS, and consensus genomes generated were used for analysis using Cluster Investigation and Virus Epidemiological Tool software. Patient timelines were obtained using electronic hospital records. Findings In total, 787 patients discharged from hospitals to care homes were identified. Of these, 776 (99%) were ruled out for subsequent introduction of SARS-CoV-2 into care homes. However, for 10 episodes, the results were inconclusive as there was low genomic diversity in consensus genomes or no sequencing data were available. Only one discharge episode had a genomic, time and location link to positive cases during hospital admission, leading to 10 positive cases in their care home. Conclusion The majority of patients discharged from hospitals were ruled out for introduction of SARS-CoV-2 into care homes, highlighting the importance of screening all new admissions when faced with a novel emerging virus and no available vaccine

    SARS-CoV-2 Omicron is an immune escape variant with an altered cell entry pathway

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    Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone of the public health response to COVID-19. The emergence of hypermutated, increasingly transmissible variants of concern (VOCs) threaten this strategy. Omicron (B.1.1.529), the fifth VOC to be described, harbours multiple amino acid mutations in spike, half of which lie within the receptor-binding domain. Here we demonstrate substantial evasion of neutralization by Omicron BA.1 and BA.2 variants in vitro using sera from individuals vaccinated with ChAdOx1, BNT162b2 and mRNA-1273. These data were mirrored by a substantial reduction in real-world vaccine effectiveness that was partially restored by booster vaccination. The Omicron variants BA.1 and BA.2 did not induce cell syncytia in vitro and favoured a TMPRSS2-independent endosomal entry pathway, these phenotypes mapping to distinct regions of the spike protein. Impaired cell fusion was determined by the receptor-binding domain, while endosomal entry mapped to the S2 domain. Such marked changes in antigenicity and replicative biology may underlie the rapid global spread and altered pathogenicity of the Omicron variant

    The influence of a sensitive period for auditory-visual integration in children with cochlear implants

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    PURPOSE: Children who experience long periods of auditory deprivation are susceptible to large-scale reorganization of auditory cortical areas responsible for the perception of speech and language. One consequence of this reorganization is that integration of combined auditory and visual information may be altered after hearing is restored with a cochlear implant. Our goal was to investigate the effects of reorganization in a task that examines performance during multisensory integration. METHODS: Reaction times to the detection of basic auditory (A), visual (V), and combined auditory-visual (AV) stimuli were examined in a group of normally hearing children, and in two groups of cochlear implanted children: (1) early implanted children in whom cortical auditory evoked potentials (CAEPs) fell within normal developmental limits, and (2) late implanted children in whom CAEPs were outside of normal developmental limits. Miller\u27s test of the race model inequality was performed for each group in order to examine the effects of auditory deprivation on multisensory integration abilities after implantation. RESULTS: Results revealed a significant violation of the race model inequality in the normally hearing and early implanted children, but not in the group of late implanted children. CONCLUSION: These results suggest that coactivation to multi-modal sensory input cannot explain the decreased reaction times to multi-modal input in late implanted children. These results are discussed in regards to current models for coactivation to redundant sensory information

    Ondansetron reduces nausea and vomiting after paediatric adenotonsillectomy

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    The efficacy, safety and resource implications of a single intravenous dose of ondansetron (0.1 mg.kg-1, maximum 4 mg) were assessed in a multinational, multicentre, randomized, double-blind, placebo-controlled trial of 427 children aged 1-12 years, undergoing tonsillectomy with/without adenoidectomy. Emesis (retching and/or vomiting) and nausea were analysed separately. Significantly more ondansetron-treated children had no episodes of emesis (127/212 (60%) vs 100/215 (47%); P = 0.004) and experienced no postoperative nausea (135/211 (64%) vs 108/213 (51%); P = 0.004) in the first 24 h. Ondansetron also reduced the number of emetic episodes (P<0.001), the time to the first emetic episode (P<0.001) and overall nausea severity (P = 0.003). Significantly fewer ondansetron-treated children were rescued or withdrawn from the study (5% vs 10%; P = 0.042). Fewer ondansetron-treated patients required nursing intervention (34% vs 45%; P = 0.007) and the average intervention time was significantly shorter (4.6 vs 8.1 minutes; P = 0.001). Resources used to manage PONV were significantly reduced by ondansetron (43% vs 57%; P = 0.014).SCOPUS: ar.jinfo:eu-repo/semantics/publishe
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