76 research outputs found

    Analysing actor based reactions to real estate features in fast-growing urban areas

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    This paper provides new insights for analyzing relations between actors and factors within urban development areas. Additionally, it contributes to basic characteristics and importance of classified actors in an urban development process. A study was defined, as part of a PhD research project to identify actors based reactions for decision making concerning real estate features in an urban development area. It is based on the analysis and comparison of possible methodologies and techniques to investigate such actor’s involvement in urban development processes. As a result a technique selection choice is presented for analyzing such actors based reactions. Better understanding of their characteristics concerning actions and links between actors will clarify their goals and interests. This paper provides a) an initial input for modeling urban development process such as: multi-actor environment, factors influencing decisions of actors and b) bring better insights in a development process which engages previous components. Further on, used and promising methodologies will be discussed considering modeling a specific actor behavior with relevant factors

    Comparability of six different immunoassays measuring SARS-CoV-2 antibodies with neutralizing antibody levels in convalescent plasma: From utility to prediction

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    Background: Convalescent plasma (CP) therapy for coronavirus disease (COVID-19) provides virus-neutralizing antibodies that may ameliorate the outcome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The effectiveness of CP likely depends on its antiviral neutralizing potency and is determined using in vitro neutralizing antibody assays. Study design and methods: We evaluated abilities of three immunoassays for anti-spike antibodies (EUROimmun, Ortho, Roche), a pseudotype-based neutralization assay, and two assays that quantify ACE2 binding of spike protein (GenScript and hemagglutination test [HAT]-based assay) to predict neutralizing antibody titers in 113 CP donations. Assay outputs were analyzed through linear regression and calculation of sensitivities and specificities by receiver operator characteristic (ROC) analysis. Results: Median values of plasma samples containing neutralizing antibodies produced conversion factors for assay unitage of ×6.5 (pseudotype), ×19 (GenScript), ×3.4 (HAT assay), ×0.08 (EUROimmun), ×1.64 (Roche), and ×0.10 (Ortho). All selected assays were sufficient in identifying the high titer donations based on ROC analysis; area over curve ranged from 91.7% for HAT and GenScript assay to 95.6% for pseudotype assay. However, their ability to predict the actual neutralizing antibody levels varied substantially as shown by linear regression correlation values (from 0.27 for Ortho to 0.61 for pseudotype assay). Discussion: Overall, the study data demonstrate that all selected assays were effective in identifying donations with high neutralizing antibody levels and are potentially suitable as surrogate assays for donation selection for CP therapy

    Microbiological contamination of cubicle curtains in an out-patient podiatry clinic

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    <p>Abstract</p> <p>Background</p> <p>Exposure to potential pathogens on contaminated healthcare garments and curtains can occur through direct or indirect contact. This study aimed to identify the microorganisms present on podiatry clinic curtains and measure the contamination pre and post a standard hospital laundry process.</p> <p>Method</p> <p>Baseline swabs were taken to determine colony counts present on cubical curtains before laundering. Curtains were swabbed again immediately after, one and three weeks post laundering. Total colony counts were calculated and compared to baseline, with identification of micro-organisms.</p> <p>Results</p> <p>Total colony counts increased very slightly by 3% immediately after laundry, which was not statistically significant, and declined significantly (p = 0.0002) by 56% one-week post laundry. Three weeks post laundry colony counts had increased by 16%; although clinically relevant, this was not statistically significant. The two most frequent microorganisms present throughout were <it>Coagulase Negative Staphylococcus </it>and <it>Micrococcus </it>species. Laundering was not completely effective, as both species demonstrated no significant change following laundry.</p> <p>Conclusion</p> <p>This work suggests current laundry procedures may not be 100% effective in killing all microorganisms found on curtains, although a delayed decrease in total colony counts was evident. Cubicle curtains may act as a reservoir for microorganisms creating potential for cross contamination. This highlights the need for additional cleaning methods to decrease the risk of cross infection and the importance of maintaining good hand hygiene.</p

    Heterologous infection and vaccination shapes immunity against SARS-CoV-2 variants

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    [Figure: see text].The impact of initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infecting strain on downstream immunity to heterologous variants of concern (VOC) is unknown. Studying a longitudinal healthcare worker cohort, we found that after three antigen exposures (infection+two vaccine doses), S1 antibody, memory B cells and heterologous neutralization of B.1.351, P.1 and B.1.617.2 plateaued, while B.1.1.7 neutralization and spike T cell responses increased. Serology using Wuhan Hu-1 spike receptor binding domain poorly predicted neutralizing immunity against VOCs. Neutralization potency against VOCs changed with heterologous virus encounter and number of antigen exposures. Neutralization potency fell differentially depending on targeted VOCs over 5-months from the second vaccine dose. Heterologous combinations of spike encountered during infection and vaccination shape subsequent cross-protection against VOC, with implications for future-proof next-generation vaccines

    COVID-19 vaccine effectiveness against hospitalisation and death of people in clinical risk groups during the Delta variant period: English primary care network cohort study.

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    BACKGROUND: COVID-19 vaccines have been shown to be highly effective against hospitalisation and death following COVID-19 infection. COVID-19 vaccine effectiveness estimates against severe endpoints among individuals with clinical conditions that place them at increased risk of critical disease are limited. METHODS: We used English primary care medical record data from the Oxford-Royal College of General Practitioners Research and Surveillance Centre sentinel network (N > 18 million). Data were linked to the National Immunisation Management Service database, Second Generation Surveillance System for virology test data, Hospital Episode Statistics, and death registry data. We estimated adjusted vaccine effectiveness (aVE) against COVID-19 infection followed by hospitalisation and death among individuals in specific clinical risk groups using a cohort design during the delta-dominant period. We also report mortality statistics and results from our antibody surveillance in this population. FINDINGS: aVE against severe endpoints was high, 14-69d following a third dose aVE was 96.4% (95.1%-97.4%) and 97.9% (97.2%-98.4%) for clinically vulnerable people given a Vaxzevria and Comirnaty primary course respectively. Lower aVE was observed in the immunosuppressed group: 88.6% (79.1%-93.8%) and 91.9% (85.9%-95.4%) for Vaxzevria and Comirnaty respectively. Antibody levels were significantly lower among the immunosuppressed group than those not in this risk group across all vaccination types and doses. The standardised case fatality rate within 28 days of a positive test was 3.9/1000 in people not in risk groups, compared to 12.8/1000 in clinical risk groups. Waning aVE with time since 2nd dose was also demonstrated, for example, Comirnaty aVE against hospitalisation reduced from 96.0% (95.1-96.7%) 14-69days post-dose 2-82.9% (81.4-84.2%) 182days+ post-dose 2. INTERPRETATION: In all clinical risk groups high levels of vaccine effectiveness against severe endpoints were seen. Reduced vaccine effectiveness was noted among the immunosuppressed group

    Prior infection with SARS-CoV-2 boosts and broadens Ad26.COV2.S immunogenicity in a variant-dependent manner

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    The Johnson and Johnson Ad26.COV2.S single-dose vaccine represents an attractive option for coronavirus disease 2019 (COVID-19) vaccination in countries with limited resources. We examined the effect of prior infection with different SARS-CoV-2 variants on Ad26.COV2.S immunogenicity. We compared participants who were SARS-CoV-2 naive with those either infected with the ancestral D614G virus or infected in the second wave when Beta predominated. Prior infection significantly boosts spike-binding antibodies, antibody-dependent cellular cytotoxicity, and neutralizing antibodies against D614G, Beta, and Delta; however, neutralization cross-reactivity varied by wave. Robust CD4 and CD8 T cell responses are induced after vaccination, regardless of prior infection. T cell recognition of variants is largely preserved, apart from some reduction in CD8 recognition of Delta. Thus, Ad26.COV2.S vaccination after infection could result in enhanced protection against COVID-19. The impact of the infecting variant on neutralization breadth after vaccination has implications for the design of second-generation vaccines based on variants of concern

    Cellulase recycling in biorefineriesis : is it possible?

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    On a near future, bio-based economy will assume a key role in our lives. Lignocellulosic materials (e.g., agroforestry residues, industrial/solid wastes) represent a cheaper and environmentally friendly option to fossil fuels. Indeed, following suitable processing, they can be metabolized by different microorganisms to produce a wide range of compounds currently obtained by chemical synthesis. However, due to the recalcitrant nature of these materials, they cannot be directly used by microorganisms, the conversion of polysaccharides into simpler sugars being thus required. This conversion, which is usually undertaken enzymatically, represents a significant part on the final cost of the process. This fact has driven intense efforts on the reduction of the enzyme cost following different strategies. Here, we describe the fundamentals of the enzyme recycling technology, more specifically, cellulase recycling. We focus on the main strategies available for the recovery of both the liquid- and solid-bound enzyme fractions and discuss the relevant operational parameters (e.g., composition, temperature, additives, and pH). Although the efforts from the industry and enzyme suppliers are primarily oriented toward the development of enzyme cocktails able to quickly and effectively process biomass, it seems clear by now that enzyme recycling is technically possible.Financial support from FEDER and Fundação para a Ciência e a Tecnologia (FCT): GlycoCBMs Project PTDC/AGR-FOR/3090/2012–FCOMP-01-0124- FEDER-027948 and Strategic Project PEst-OE/EQB/LA0023/2013, Project BBioInd-Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028 Cofunded by the Programa Operacional Regional do Norte (ON.2–O Novo Norte), QREN, FEDER and the PhD grant to DG (SFRH/BD/88623/ 2012) and ACR (SFRH/BD/89547/2012)
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