742 research outputs found

    Proposing a life cycle land use impact calculation methodology

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    The Life Cycle Assessment (LCA) community is yet to come to a consensus on a methodology to incorporate land use in LCA, still struggling with what exactly should be assessed and which indicators should be used. To solve this problem we start from concepts and models describing how ecosystems function and sustain, in order to understand how land use affects them. Earlier our research group presented a methodology based on the ecosystem exergy concept. This concept as based on the hypothesis that ecosystems develop towards more effective degradation of exergy fluxes passing through the system and is derived from two axioms: the principles of (i) maximum exergy storage and the (ii) maximum exergy dissipation. This concept aiming at the area of protection natural environment is different from conventional exergy analysis in LCA focusing on natural resources. To prevent confusion, the ecosystem exergy concept is further referred to as the MAximum Storage and Dissipation concept (MASD concept). In this paper we present how this concept identifies end-point impacts, mid-point impacts and mid-point indicators. The identified end-point impacts to assess are Ecosystem Structural Quality (ESQ) and Ecosystem Functional Quality (EFQ). In order to quantify these end-point impacts a dynamic multi-indicator set is proposed for quantifying the mid-point impacts on soil fertility, biodiversity and biomass production (quantifying the ESQ) and soil structure, vegetation structure and on-site water balance (quantifying the EFQ). Further we present an impact calculation method suitable for different environmental assessment tools and demonstrate the incorporation of the methodology in LCA

    Use of inadequate data and methodological errors lead to a dramatic overestimation of the water footprint of Jatropha curcas

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    In their recent article, Gerbens-Leenes et al. (1) calculated the water footprint (WF, the amount of water required to produce 1 GJ of energy) of several bioenergy crops. One of the most remarkable findings of this study was the very high water footprint of this species, which has serious management consequences. 

However, these results are in apparent contrast with recent findings on this species. We present evidence that several errors were made by the authors when calculating the water footprint of jatropha, which has lead to a dramatic overestimation. These errors include weaknesses concerning the data used for the calculation of the water footprint, as well as flaws in the calculation method, as we demonstrate in the letter. Based on peer-reviewed data, we furthermore provide a more correct, still rough, first estimate for the water footprint of this species, which would place it amongst the more water efficient bioenergy crops. 

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    Proposing a life cycle land use impact calculation methodology

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    The Life Cycle Assessment (LCA) community is yet to come to a consensus on a methodology to incorporate land use in LCA. Earlier our research group presented a methodology based on the ecosystem exergy concept. The ecosystem exergy concept suggests that ecosystems develop towards more effective degradation of energy fluxes passing through the system. The concept is argued to be derivable from two axioms: the principles of (i) maximum exergy storage and the (ii) maximum exergy dissipation. In this paper we present a methodology to assess impacts of human induced land use occupation, in which we make a difference between functional and structural land use impacts. The methodology follows a dynamic multi-indicator approach looking at mid-point impacts on soil fertility, soil structure, biomass production, vegetation structure, on-site water balance and biodiversity. The impact scores are calculated as a relative difference with a reference system. We propose to calculate the impact by calculating the land quality change between the former and the actual land use relative to the quality of the potential natural vegetation. Impact scores are then aggregated, as endpoint impacts, in (i) structural land use impact (exergy storage capacity) and (ii) functional land use impact (exergy dissipation capacity). For aggregation of the relative mid-point impact scores no characterization factor is used. In order to fit this impact calculation in the LCA framework the end-point impact scores are multiplied by a LCA component, a component that enables us to report the impact per functional unit

    Borealis sound an interactive wall for situational awareness: The impact of responsive architecture on users

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    This paper refers to the presence of visual communication elements in public spaces using interactive multimedia surfaces. The state of the art, the development of a proposal, and its evaluation are presented. The interactive surface applies to school of music “Escola de Música do Conservatório Nacional,” to which a design project was done in an academic context. The proposal aims to explore the incorporation of digital multimedia surfaces enhancing new dynamics while users walk in the interior of the building. Visual content will be displayed, and the interaction between users and the multimedia surfaces is done by the sounds produce by people and instruments. To assess the intuitive nature and relevance of the proposal, satisfaction and usability tests were conducted with the potential users. It was concluded that users appreciated the proposal and was able to perceive the effect people’s presence have in the interaction with the multimedia surface.info:eu-repo/semantics/acceptedVersio

    The effect of surgical approach on the histology of the femoral head following resurfacing of the hip : analysis of retrieval specimens

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    Objectives: We aimed to determine the effect of surgical approach on the histology of the femoral head following resurfacing of the hip. Methods: We performed a histological assessment of the bone under the femoral component taken from retrieval specimens of patients having revision surgery following resurfacing of the hip. We compared the number of empty lacunae in specimens from patients who had originally had a posterior surgical approach with the number in patients having alternative surgical approaches. Results: We found a statistically significant increase in the percentage of empty lacunae in retrieval specimens from patients who had the posterior approach compared with other surgical approaches (p < 0.001). Conclusions: This indicates that the vascular compromise that occurs during the posterior surgical approach does have long-term effects on the bone of the femoral head, even if it does not cause overt avascular necrosis

    P23 Associate Principal Investigators in Trauma Trials

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    Kombination der Analyse von Black Carbon, PAK und organischen Geosorbenten in urbanen Böden als Indikator für die Bioverfügbarkeit von PAK

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    In den letzten Jahren hat die Bedeutung von aromatischen Kohlenwasserstoffmolekülen in umweltrelevanten Fragestellungen zugenommen: Toxizität und Bioverfügbarkeit von polyzyklischen aromatischen Kohlenwasserstoffen (PAK), die Bindung dieser Substanzen an Geosorbenten und die damit verbundene reduzierte Freisetzungsrate, sowie die Differenzierung des organischen Kohlenstoffs (TOC) in Böden in reaktive und gering reaktive Kohlenstoffpools (Black Carbon) im Hinblick auf Kohlenstoffspeicherung, die Verwertbarkeit von Böden mit erhöhten TOC- und PAK-Gehalten und Biochar. Die Herkunft dieser aromatischen Moleküle aus biogenen, petrogenen oder pyrogenen Quellen ist hierbei von besonderer Bedeutung, da sich die Bildungsmechanismen unterscheiden und ggf. charakteristische Moleküle oder Molekül-Muster gebildet werden. PAK und Black Carbon sind eng miteinander verbunden, letztlich bestehen die größeren Black Carbon-Strukturen wesentlich aus den zahlreichen PAK bzw. können aus diesen durch Koagulation gebildet werden. Andererseits können PAK als „mobile Phase“ zwischen den größeren 3-dimensionalen Kohlenwasserstoffstrukturen des Kerogen z. B. in Kohlen enthalten sein. Die Vielfalt der durch überwiegend anthropogene Prozesse schließlich in Böden vorliegenden Arten von TOC-haltigen technogenen Substraten sowie Gemischen ist groß und kann mittels organisch-petrographischer Methoden identifiziert und quantifiziert werden. In dieser Studie werden systematische Zusammenhänge zwischen petrogenen und pyrogenen PAK, Black Carbon anhand der Aromatizität und des Grades der aromatischen Kondensation (Benzenpolycarbonsäuren(BPCA)-Methode mittels Flüssigchromatographie-Massenspektrometrie) sowie der petrographischen mikroskopischen Analyse gezeigt. Als Probenset dienten Ruße (z. B. Diesel, Holz), Aschen, Schlacken, Lignit, Braun- und Steinkohlen sowie Anthrazit, Bergematerial, Kohleschlamm, Holzkohlen, Kokse unterschiedlicher Herkunft, Stäube, Rohöle, Teeröle sowie Böden mit Mischungen von technogenen Substraten aus dem Ruhrgebiet. Hinzugefügte Literaturdaten bestätigen die Messergebnisse im Kohlenstoffkontinuum. Untersuchungen der Freisetzung von PAK in die wässrige Phase sowie ihrer Resorptionsverfügbarkeit weisen auf ein allgemein geringes Potential im thermisch beeinflussten Teil des Kohlenstoffkontinuums hin

    Factors Associated with Prolonged Antibiotic Therapy in Neonates with Suspected Early-Onset Sepsis

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    Early-onset sepsis (EOS) is a rare but profoundly serious bacterial infection. Neonates at risk of EOS are often treated with antibiotics. The start of empiric antibiotic therapy can successfully be reduced by the implementation of the EOS calculator. However, once started, antibiotic therapy is often continued despite a negative blood culture. To decrease the burden of antibiotic therapy, it is necessary to know whether the clinician’s reasons are based on objective factors. Therefore, we performed a retrospective single-centre cohort study to identify the factors associated with prolongation of antibiotic therapy in neonates with suspected EOS but a negative blood culture. Maternal, clinical, and laboratory data of neonates with a gestational age of ≥32 weeks, admitted between January 2019 and June 2021, were collected. Among neonates with a negative blood culture, we compared neonates with prolonged (≥3 days) to neonates with discontinued (&lt;3 days) antibiotic therapy. The clinician’s reported reasons for prolonging therapy were explored. Blood cultures were positive in 4/146 (2.7%), negative in 131/146 (89.7%), and not obtained in 11/146 (7.5%) of the neonates. The incidence of EOS was 0.7 per 1000 neonates. Of the 131 neonates with a negative blood culture, 47 neonates (35.9%) received prolonged antibiotic therapy. In the prolonged group, the mean gestational age was higher (38.9 versus 36.8 weeks), and spontaneous preterm birth was less prevalent (21.3% versus 53.6%). Prolonged treatment was associated with late onset of respiratory distress, respiratory rate, hypoxia, apnoea and bradycardia, pale appearance, behavioural change, and elevated CRP levels. The most reported reasons were clinical appearance (38.3%), elevated CRP levels (36.2%), and skin colour (10.6%). Prolonging empiric antibiotic therapy despite a negative blood culture is common in suspected EOS. Clinical signs associated with prolongation are uncommon and the reported reasons for prolongation contain subjective assessments and arbitrary interpretations that are not supported by the guideline recommendations as arguments for prolonged therapy.</p

    Factors Associated with Prolonged Antibiotic Therapy in Neonates with Suspected Early-Onset Sepsis

    Get PDF
    Early-onset sepsis (EOS) is a rare but profoundly serious bacterial infection. Neonates at risk of EOS are often treated with antibiotics. The start of empiric antibiotic therapy can successfully be reduced by the implementation of the EOS calculator. However, once started, antibiotic therapy is often continued despite a negative blood culture. To decrease the burden of antibiotic therapy, it is necessary to know whether the clinician’s reasons are based on objective factors. Therefore, we performed a retrospective single-centre cohort study to identify the factors associated with prolongation of antibiotic therapy in neonates with suspected EOS but a negative blood culture. Maternal, clinical, and laboratory data of neonates with a gestational age of ≥32 weeks, admitted between January 2019 and June 2021, were collected. Among neonates with a negative blood culture, we compared neonates with prolonged (≥3 days) to neonates with discontinued (&lt;3 days) antibiotic therapy. The clinician’s reported reasons for prolonging therapy were explored. Blood cultures were positive in 4/146 (2.7%), negative in 131/146 (89.7%), and not obtained in 11/146 (7.5%) of the neonates. The incidence of EOS was 0.7 per 1000 neonates. Of the 131 neonates with a negative blood culture, 47 neonates (35.9%) received prolonged antibiotic therapy. In the prolonged group, the mean gestational age was higher (38.9 versus 36.8 weeks), and spontaneous preterm birth was less prevalent (21.3% versus 53.6%). Prolonged treatment was associated with late onset of respiratory distress, respiratory rate, hypoxia, apnoea and bradycardia, pale appearance, behavioural change, and elevated CRP levels. The most reported reasons were clinical appearance (38.3%), elevated CRP levels (36.2%), and skin colour (10.6%). Prolonging empiric antibiotic therapy despite a negative blood culture is common in suspected EOS. Clinical signs associated with prolongation are uncommon and the reported reasons for prolongation contain subjective assessments and arbitrary interpretations that are not supported by the guideline recommendations as arguments for prolonged therapy.</p
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