2,076 research outputs found

    Organic Carbon Emissions from the Co-firing of Coal and Wood in a Fixed Bed Combustor

    Get PDF
    Co-firing of biomass and coal and biomass reduces the emission of pollutants and the overall effects have been extensively studied, but many aspects of the detailed mechanism remain uncertain. A number of studies have been previously made by us of emissions from the combustion in a fixed-bed furnace of bituminous coal and wood, both individually and together, and it was observed that biomass produced less soot and lower NOX emissions. These data are combined with recent measurements of emissions of black carbon (BC) and organic carbon (OC), which are an important source of climate forcing, from the combustion of a number of solid fuels. Conclusion are drawn about the nature of the OC and how the values are dependent on the measurement technique used. Complementary analytical-scale combustion and pyrolysis experiments were also carried out. The results of the analysis of emissions and reaction products, mainly by gas chromatography–mass spectrometry (GC–MS), were interpreted so as to construct a model for pollutant formation during co-firing

    Mitchell–Hoole–Kanatas (MHK) questionnaire: the first to measure patient-reported outcomes relating to problems with intimacy after diagnosis and treatment of head and neck cancer

    Get PDF
    Patient-reported outcomes are increasingly used by clinical teams as indicators of quality when assessing treatment after a diagnosis of head and neck cancer. About a third of patients report reduced sexual interest or enjoyment after such treatment but, despite that, there is no questionnaire about intimacy that has been developed specifically for them. The aim of this study was to develop such a questionnaire, to gain an indication of the relative incidence of individual items, and to compare characteristics such as age, stage, treatment, time since treatment for an established head and neck cancer, and a health-related quality of life (QoL) measure (European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-C30 with the Head and Neck 35 module). The development of the new instrument was based on an exploratory observational study that included quantitative and qualitative methods. The qualitative element was achieved by the generation of items - from published studies, the comments of patients and carers, and a cross-sectional survey of patients with head and neck cancer who were alive and free of disease. The quantitative element comprised analysis of exploratory and confirmatory factors, internal reliability assessment (Cronbach’s alpha), and a correlation analysis. Forty-two patients were included in the focus groups, and 101 patients participated in the cross-sectional survey (both male and female, in a relationship and single, age range 30–70 years for the focus group, and 62–117 in the cross-sectional survey). All treatments were included. We found that the ability to enjoy a sex life had been adversely affected in about half the sample and that this had significantly changed from before their cancer in a third. The qualitative part of the study resulted in 22 items that covered a range of domains from dry mouth and thick saliva to loss of sensation (lips, fingertips), restricted head/neck movement, fatigue, and pain. The exploratory analysis covered four domains (physical, sensation, movement, and communication) from 12 of 22 items. Cronbach’s alphas ranged from 0.62 to 0.84, and the correlation analysis indicated “good fit” statistics for these domains. In terms of the EORTC QoL Questionnnaire – Head and Neck 35, the four MHK domains showed good levels of association with anticipated domains. Head and neck cancer and its associated treatments significantly adversely affect intimacy and sexuality in half the population sampled. The MHK tool may be used to identify specific issues related to intimacy in patients with a history of diagnosis and treatment of head and neck cancer. Further work is essential to identify its precise role and to help develop specific interventions

    Simplified lipid II-binding antimicrobial peptides: Design, synthesis and antimicrobial activity of bioconjugates of nisin rings A and B with pore-forming peptides

    Get PDF
    New designs of antimicrobial peptides are urgently needed in order to combat the threat posed by the recent increase of resistance to antibiotics. In this paper, we present a new series of antimicrobial peptides, based on the key structural features of the lantibiotic nisin. We have simplified the structure of nisin by conjugating the lipid II-binding motif at the N-terminus of nisin to a series of cationic peptides and peptoids with known antibacterial action and pore-forming properties. Hybrid peptides, where a hydrophilic PEG4 linker was used, showed good antibacterial activity against Micrococcus luteus

    A dynamic network approach for the study of human phenotypes

    Get PDF
    The use of networks to integrate different genetic, proteomic, and metabolic datasets has been proposed as a viable path toward elucidating the origins of specific diseases. Here we introduce a new phenotypic database summarizing correlations obtained from the disease history of more than 30 million patients in a Phenotypic Disease Network (PDN). We present evidence that the structure of the PDN is relevant to the understanding of illness progression by showing that (1) patients develop diseases close in the network to those they already have; (2) the progression of disease along the links of the network is different for patients of different genders and ethnicities; (3) patients diagnosed with diseases which are more highly connected in the PDN tend to die sooner than those affected by less connected diseases; and (4) diseases that tend to be preceded by others in the PDN tend to be more connected than diseases that precede other illnesses, and are associated with higher degrees of mortality. Our findings show that disease progression can be represented and studied using network methods, offering the potential to enhance our understanding of the origin and evolution of human diseases. The dataset introduced here, released concurrently with this publication, represents the largest relational phenotypic resource publicly available to the research community.Comment: 28 pages (double space), 6 figure

    Multi-Timescale Perceptual History Resolves Visual Ambiguity

    Get PDF
    When visual input is inconclusive, does previous experience aid the visual system in attaining an accurate perceptual interpretation? Prolonged viewing of a visually ambiguous stimulus causes perception to alternate between conflicting interpretations. When viewed intermittently, however, ambiguous stimuli tend to evoke the same percept on many consecutive presentations. This perceptual stabilization has been suggested to reflect persistence of the most recent percept throughout the blank that separates two presentations. Here we show that the memory trace that causes stabilization reflects not just the latest percept, but perception during a much longer period. That is, the choice between competing percepts at stimulus reappearance is determined by an elaborate history of prior perception. Specifically, we demonstrate a seconds-long influence of the latest percept, as well as a more persistent influence based on the relative proportion of dominance during a preceding period of at least one minute. In case short-term perceptual history and long-term perceptual history are opposed (because perception has recently switched after prolonged stabilization), the long-term influence recovers after the effect of the latest percept has worn off, indicating independence between time scales. We accommodate these results by adding two positive adaptation terms, one with a short time constant and one with a long time constant, to a standard model of perceptual switching

    Vertical zonation of testate amoebae in the Elatia Mires, northern Greece : palaeoecological evidence for a wetland response to recent climate change or autogenic processes?

    Get PDF
    The Elatia Mires of northern Greece are unique ecosystems of high conservation value. The mires are climatically marginal and may be sensitive to changing hydroclimate, while northern Greece has experienced a significant increase in aridity since the late twentieth century. To investigate the impact of recent climatic change on the hydrology of the mires, the palaeoecological record was investigated from three near-surface monoliths extracted from two sites. Testate amoebae were analysed as sensitive indicators of hydrology. Results were interpreted using transfer function models to provide quantitative reconstructions of changing water table depth and pH. AMS radiocarbon dates and 210Pb suggest the peats were deposited within the last c. 50 years, but do not allow a secure chronology to be established. Results from all three profiles show a distinct shift towards a more xerophilic community particularly noted by increases in Euglypha species. Transfer function results infer a distinct lowering of water tables in this period. A hydrological response to recent climate change is a tenable hypothesis to explain this change; however other possible explanations include selective test decay, vertical zonation of living amoebae, ombrotrophication and local hydrological change. It is suggested that a peatland response to climatic change is the most probable hypothesis, showing the sensitivity of marginal peatlands to recent climatic change

    Attitudes About COVID-19 and Health (ATTACH): Online Survey and Mixed Methods Study

    Get PDF
    Background: Behavioral mitigation strategies to slow the spread of COVID-19 have resulted in sweeping lifestyle changes, with short- and long-term psychological, well-being, and quality of life implications. The Attitudes About COVID-19 and Health (ATTACH) study focuses on understanding attitudes and beliefs while considering the impact on mental and physical health and the influence of broader demographic and geographic factors on attitudes, beliefs, and mental health burden. / Objective: In this assessment of our first wave of data collection, we provide baseline cohort description of the ATTACH study participants in the United Kingdom, the United States, and Mexico. Additionally, we assess responses to daily poll questions related to COVID-19 and conduct a cross-sectional analysis of baseline assessments collected in the UK between June 26 and October 31, 2020. / Methods: The ATTACH study uses smartphone app technology and online survey data collection. Participants completed poll questions related to COVID-19 2 times daily and a monthly survey assessing mental health, social isolation, physical health, and quality of life. Poll question responses were graphed using 95% Clopper–Pearson (exact) tests with 95% CIs. Pearson correlations, hierarchical linear regression analyses, and generalized linear models assessed relationships, predictors of self-reported outcomes, and group differences, respectively. / Results: By October 31, 2020, 1405, 80, and 90 participants had consented to participate in the UK, United States, and Mexico, respectively. Descriptive data for the UK daily poll questions indicated that participants generally followed social distancing measures, but worry and negative impacts on families increased as the pandemic progressed. Although participants generally reported feeling that the reasons for current measures had been made clear, there was low trust that the government was doing everything in its power to meet public needs. In the UK, 1282 participants also completed a monthly survey (94.99% [1326/1396] White, 72.22% [1014/1404] female, and 20.12% [277/1377] key or essential workers); 18.88% (242/1282) of UK participants reported a preexisting mental health disorder, 31.36% (402/1282) reported a preexisting chronic medical illness, and 35.11% (493/1404) were aged over 65; 57.72% (740/1282) of participants reported being more sedentary since the pandemic began, and 41.89% (537/1282) reported reduced access to medical care. Those with poorer mental health outcomes lived in more deprived neighborhoods, in larger households (Ps<.05), had more preexisting mental health disorders and medical conditions, and were younger than 65 years (all Ps<.001). / Conclusions: Communities who have been exposed to additional harm during the COVID-19 pandemic were experiencing worse mental outcomes. Factors including having a medical condition, or living in a deprived neighborhood or larger household were associated with heightened risk. Future longitudinal studies should investigate the link between COVID-19 exposure, mental health, and sociodemographic and residential characteristics
    corecore