257 research outputs found

    Assessment of the Impact of Window Size, Position and Orientation on Building Energy Load Using BIM

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    AbstractIn improving energy efficiency of buildings, windows play a significant role as they largely influence the energy load. Although there are many studies about the energy efficient window design, a rigorous study is missing which analyzes the mutual impact of windows’ size, position and orientation on the energy load. This study aims to address this gap through a case study on a single family house. For this aim, 65 different design scenarios are created which vary by window size, position and orientation. Building information models (BIMs) are created for each scenario via Autodesk Revit®, and are used for the calculation of the total energy load conducted by Autodesk Green Building Studio®. In the first analysis stage, window-to-wall ratio (WWR) and the windows’ position are studied to assess their effect on the energy load. The preliminary results at this stage indicate that the total energy load increases when the WWR grows, and the windows’ position has the biggest impact on the load when the WWR is 20. Using these results, in the next stage, the position of windows in different orientation is studied to assess how the energy load changes by windows’ position in each orientation. The results show that the building requires the lowest load when the windows are located in the middle height in all orientations, and the east windows’ positioning affects the total energy load the most

    A pilot study of transrectal endoscopic ultrasound elastography in inflammatory bowel disease

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    BACKGROUND: Using standard diagnostic algorithms it is not always possible to establish the correct phenotype of inflammatory bowel disease which is essential for therapeutical decisions. Endoscopic ultrasound elastography is a new endoscopic procedure which can differentiate the stiffness of normal and pathological tissue by ultrasound. Therefore, we aimed to investigate the role of transrectal ultrasound elastography in distiction between Crohn's disease and ulcerative colitis. ----- METHODS: A total 30 Crohn's disease, 25 ulcerative colitis, and 28 non-inflammatory bowel disease controls were included. Transrectal ultrasound elastography was performed in all patients and controls. In all ulcerative coltis patients and 80% of Crohn's disease patients endoscopy was performed to assess disease activity in the rectum. ----- RESULTS: Significant difference in rectal wall thickness and strain ratio was detected between patients with Crohn's disease and controls (p = 0.0001). CD patients with active disease had higher strain ratio than patients in remission (p = 0.02). In ulcerative colitis group a significant difference in rectal wall thickness was found between controls and patients with active disease (p = 0.03). A significant difference in rectal wall thickness (p = 0.02) and strain ratio (p = 0.0001) was detected between Crohn's disease and ulcerative colitis patient group. Crohn's disease patients with active disease had a significantly higher strain ratio compared to ulcerative colitis patients with active disease (p = 0.0001). ----- CONCLUSION: Transrectal ultrasound elastography seems to be a promising new diagnostic tool in the field of inflammatory bowel disease. Further study on a larger cohort of patients is needed to definitely assess the role of transrectal ultrasound elastography in inflammatory bowel disease

    Chemical diversity in a metal-organic framework revealed by fluorescence lifetime imaging

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    The presence and variation of chemical functionality and defects in crystalline materials, such as metal–organic frameworks (MOFs), have tremendous impact on their properties. Finding a means of identifying and characterizing this chemical diversity is an important ongoing challenge. This task is complicated by the characteristic problem of bulk measurements only giving a statistical average over an entire sample, leaving uncharacterized any diversity that might exist between crystallites or even within individual crystals. Here we show that by using fluorescence imaging and lifetime analysis, both the spatial arrangement of functionalities and the level of defects within a multivariable MOF crystal can be determined for the bulk as well as for the individual constituent crystals. We apply these methods to UiO-67, to study the incorporation of functional groups and their consequences on the structural features. We believe that the potential of the techniques presented here in uncovering chemical diversity in what is generally assumed to be homogeneous systems can provide a new level of understanding of materials properties

    Highly Water-Stable Zirconium Metal-Organic Framework UiO-66 Membranes Supported on Alumina Hollow Fibers for Desalination

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    In this study, continuous zirconium(IV)-based metal-organic framework (Zr-MOF) membranes were prepared. The pure-phase Zr-MOF (i.e., UiO-66) polycrystalline membranes were fabricated on alumina hollow fibers using an in situ solvothermal synthesis method. Single-gas permeation and ion rejection tests were carried out to confirm membrane integrity and functionality. The membrane exhibited excellent multivalent ion rejection (e.g., 86.3% for Ca2+, 98.0% for Mg2+, and 99.3% for Al3+) on the basis of size exclusion with moderate permeance (0.14 L m-2 h-1 bar-1) and good permeability (0.28 L m-2 h-1 bar-1 μm). Benefiting from the exceptional chemical stability of the UiO-66 material, no degradation of membrane performance was observed for various tests up to 170 h toward a wide range of saline solutions. The high separation performance combined with its outstanding water stability suggests the developed UiO-66 membrane as a promising candidate for water desalination

    Environmental factors in a population-based inception cohort of inflammatory bowel disease patients in Europe--an ECCO-EpiCom study.

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    To access publisher's full text version of this article click on the hyperlink at the bottom of the pageThe incidence of inflammatory bowel disease (IBD) is increasing in Eastern Europe possibly due to changes in environmental factors towards a more "westernised" standard of living. The aim of this study was to investigate differences in exposure to environmental factors prior to diagnosis in Eastern and Western European IBD patients.The EpiCom cohort is a population-based, prospective inception cohort of 1560 unselected IBD patients from 31 European countries covering a background population of 10.1 million. At the time of diagnosis patients were asked to complete an 87-item questionnaire concerning environmental factors.A total of 1182 patients (76%) answered the questionnaire, 444 (38%) had Crohn's disease (CD), 627 (53%) ulcerative colitis (UC), and 111 (9%) IBD unclassified. No geographic differences regarding smoking status, caffeine intake, use of oral contraceptives, or number of first-degree relatives with IBD were found. Sugar intake was higher in CD and UC patients from Eastern Europe than in Western Europe while fibre intake was lower (p<0.01). Daily consumption of fast food as well as appendectomy before the age of 20 was more frequent in Eastern European than in Western European UC patients (p<0.01). Eastern European CD and UC patients had received more vaccinations and experienced fewer childhood infections than Western European patients (p<0.01).In this European population-based inception cohort of unselected IBD patients, Eastern and Western European patients differed in environmental factors prior to diagnosis. Eastern European patients exhibited higher occurrences of suspected risk factors for IBD included in the Western lifestyle.Danish Colitis Crohn Patients Organisation (CCF) Vibeke Binder and Povl Riis Foundation Scientific Council at Herlev Hospital Sigrid Rignnor Moran Foundation, Aage and Johanne Louis-Hansens Foundation Munkholm Foundation C.C. Klestrup and Henriette Klestrup Foundation Knud and Dagny Gad Andresens Foundation Else and Mogens Wedell-Wedellsborgs Foundation Direktor Jacob Madsen and Olga Madsen's Foundation, Scan Ve

    Postsynthetic bromination of UiO-66 analogues:altering linker flexibility and mechanical compliance

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    A new member of the UiO-66 series of zirconium metal-organic frameworks (MOFs) is reported, and the postsynthetic bromination of its integral alkene moeities in a single-crystal to single-crystal manner is fully characterised. Nanoindentation is used to show bromination of unsaturated carbon-carbon bonds in it and an analogous Zr MOF leads to more compliant materials with lower elastic moduli

    Zirconium-containing metal organic frameworks as solid acid catalysts for the esterification of free fatty acids: Synthesis of biodiesel and other compounds of interest

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    Zr-containing metal organic frameworks (MOFs) formed by terephthalate (UiO-66) and 2-aminoterephthalate ligands (UiO-66-NH2) are active and stable catalysts for the acid catalyzed esterification of various saturated and unsaturated fatty acids with MeOH and EtOH, with activities comparable (in some cases superior) to other solid acid catalysts previously reported in literature. Besides the formation of the corresponding fatty acid alkyl esters as biodiesel compounds (FAMEs and FAEEs), esterification of biomass-derived fatty acids with other alcohols catalyzed by the Zr-MOFs allows preparing other compounds of interest, such as oleyl oleate or isopropyl palmitate, with good yields under mild conditions.Financial support from the Consolider-Ingenio 2010 (project MULTICAT), the Severo Ochoa program, and the Spanish Ministry of Science and Innovation (project MAT2011-29020-C02-01) is gratefully acknowledged.García Cirujano, F.; Corma Canós, A.; Llabrés I Xamena, FX. (2015). Zirconium-containing metal organic frameworks as solid acid catalysts for the esterification of free fatty acids: Synthesis of biodiesel and other compounds of interest. Catalysis Today. 257:213-220. https://doi.org/10.1016/j.cattod.2014.08.015S21322025

    Natural Disease Course of Ulcerative Colitis During the First Five Years of Follow-up in a European Population-based Inception Cohort-An Epi-IBD Study

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    International audienceBackground and Aims: Few population-based cohort studies have assessed the disease course of ulcerative colitis [UC] in the era of biological therapy and widespread use of immunomodulators. The aim of this study was to assess the 5-year outcome and disease course of patients with UC in the Epi-IBD cohort. Methods: In a prospective, population-based inception cohort of unselected patients with UC, patients were followed up from the time of their diagnosis, which included the collection of their clinical data, demographics, disease activity, medical therapy, and rates of surgery, cancers, and deaths. Associations between outcomes and multiple covariates were analysed by Cox regression analysis. Results: A total of 717 patients were included in the study. During follow-up, 43 [6%] patients underwent a colectomy and 163 [23%] patients were hospitalised. Of patients with limited colitis [distal to the left flexure], 90 [21%] progressed to extensive colitis. In addition, 92 [27%] patients with extensive colitis experienced a regression in disease extent, which was associated with a reduced risk of hospitalisation (hazard ratio [HR]: 0.5 95% CI: 0.3-0.8]. Overall, patients were treated similarly in both geographical regions; 80 [11%] patients needed biological therapy and 210 [29%] patients received immunomodulators. Treatment with immunomodulators was found to reduce the risk of hospitalisation [HR: 0.5 95% CI: 0.3-0.8]. Conclusions: Although patients in this population-based cohort were treated more aggressively with immunomodulators and biological therapy than in cohorts from the previous two decades, their disease outcomes, including colectomy rates, were no different. However, treatment with immunomodulators was found to reduce the risk of hospitalisation
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