91 research outputs found
Enabling organizational changes for development of product-service system offers
The manufacturing industry is going through a transition from developing of products to the provision of product-service systems (PSS). Earlier research has identified different types of PSS offers, from product offers that include services as “add-on”, to the sale of services that include tangible goods as “add-on”. This paper addresses what consequences this has on manufacturing organizations undergoing PSS transition. The purpose of the paper is to clarify key success factors for organizational changes needed in the transition process of developing different types of PSS offers. The results are based on a case study of a manufacturer in the aerospace domain; the analysis approached organizational changes from organizational theory perspective. The study identified four key areas that need to be considered in the organizational transformation to PSS development: Business strategy and decision-making, Internal organizational structure, Team composition, and External networks and customer relationship. Based on the analysis of empirical data from these four areas, the paper discusses the successful organizational changes that are required in the transition towards PSS development
Pre-stressed Geodesic Gridshell
Timber gridshells can cover large spaces with minimum material. However, with\ua0long-term creep deformations, small cross sections and high elasticity, there are potential\ua0stability issues. Historically, pre-stressing systems have been shown to prevent\ua0instability modes in unstable structures. In this project we investigate the benefits\ua0of pre-stressing a geodesic elastic bending-active gridshells serving as a lecture\ua0pavilion. Digital analysis and physical tests are interactively combined to study and\ua0implement various modelling and analysis techniques, pre-stress configurations and\ua0connection details. It is found that an internal pre-stressing system can significantly\ua0increase the stability of in terms of eigenfrequencies
DERIVE AND INTEGRATE SUSTAINABILITY CRITERIA IN DESIGN SPACE EXPLORATION OF ADDITIVE MANUFACTURED COMPONENTS
Additive manufacturing has the potential to decrease the climate impact of aviation by providing more light-weight designs. Sustainability is however required to be assessed from a systemic view, including all lifecycle phases, and from a social, ecologic, and economic dimension. This is however challenging in early phase design, where also a large design space need to be explored. A case study is carried out with an aerospace company where two candidate engineering design tools are combined to address this. The integration of these two engineering tools are applied on a Turbine Rear Structure, and shows promising results in enabling a systemic view of sustainability to be integrated and assessed in early phase design space explorations of additive manufactured components. It is recommended that the integration between the two tools is further established and validated
The design , fabrication and assembly of an asymptotic timber gridshell
This paper describes and discuss the design, fabrication and assembly of an asymptotic gridshellbuilt of plywood laths. The overall question concerns how geometry, structural action, andecient production can interplay and inform spatial design. The environment is a two-dayworkshop where architects, engineers and researchers with specialization in structural and digitaldesign cooperate with undergraduate students in a compulsory parametric design and digitalfabrication course. The gridshell shape is based on an Enneper surface of threefold rotationalsymmetry with a boundary baseplate inscribed within a circle of 4.5 m in radius. Utilizing theconcept of asymptotic curves, which are surface curves whose osculating plane coincides withthe tangent plane of the surface, the structure was built using planar straight laths of plywoodmade using manually operated drills and saws
Fecal luminal factors from patients with irritable bowel syndrome induce distinct gene expression of colonoids
Background: Alteration of the host-microbiota cross talk at the intestinal barrier may participate in the pathophysiology of irritable bowel syndrome (IBS). Therefore, we aimed to determine effects of fecal luminal factors from IBS patients on the colonic epithelium using colonoids. Methods: Colon-derived organoid monolayers, colonoids, generated from a healthy subject, underwent stimulation with fecal supernatants from healthy subjects and IBS patients with predominant diarrhea, phosphate-buffered saline (PBS), or lipopolysaccharide (LPS). Cytokines in cell cultures and fecal LPS were measured by ELISA and mRNA gene expression of monolayers was analyzed using Qiagen RT2 Profiler PCR Arrays. The fecal microbiota profile was determined by the GA-map™ dysbiosis test and the fecal metabolite profile was analyzed by untargeted liquid chromatography/mass spectrometry. Key results: Colonoid monolayers stimulated with fecal supernatants from healthy subjects (n\ua0=\ua07), PBS (n\ua0=\ua04) or LPS (n\ua0=\ua03) presented distinct gene expression profiles, with some overlap (R2Y\ua0=\ua00.70, Q2=\ua00.43). Addition of fecal supernatants from healthy subjects and IBS patients (n\ua0=\ua09) gave rise to different gene expression profiles of the colonoid monolayers (R2Y\ua0=\ua00.79, Q2=\ua00.64). Genes (n\ua0=\ua022) related to immune response (CD1D, TLR5) and barrier integrity (CLDN15, DSC2) contributed to the separation. Levels of proinflammatory cytokines in colonoid monolayer cultures were comparable when stimulated with fecal supernatants from either donor types. Fecal microbiota and metabolite profiles, but not LPS content, differed between the study groups. Conclusions: Fecal luminal factors from IBS patients induce a distinct colonic epithelial gene expression, potentially reflecting the disease pathophysiology. The culture of colonoids from healthy subjects with fecal supernatants from IBS patients may facilitate the exploration of IBS related intestinal micro-environmental and barrier interactions
Bacterial extracellular vesicles: towards realistic models for bacterial membranes in molecular interaction studies by surface plasmon resonance
One way to mitigate the ongoing antimicrobial resistance crisis is to discover and develop new classes of antibiotics. As all antibiotics at some point need to either cross or just interact with the bacterial membrane, there is a need for representative models of bacterial membranes and efficient methods to characterize the interactions with novel molecules -both to generate new knowledge and to screen compound libraries. Since the bacterial cell envelope is a complex assembly of lipids, lipopolysaccharides, membrane proteins and other components, constructing relevant synthetic liposome-based models of the membrane is both difficult and expensive. We here propose to let the bacteria do the hard work for us. Bacterial extracellular vesicles (bEVs) are naturally secreted by Gram-negative and Gram-positive bacteria, playing a role in communication between bacteria, as virulence factors, molecular transport or being a part of the antimicrobial resistance mechanism. bEVs consist of the bacterial outer membrane and thus inherit many components and properties of the native outer cell envelope. In this work, we have isolated and characterized bEVs from one Escherichia coli mutant and three clinical strains of the ESKAPE pathogens Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa. The bEVs were shown to be representative models for the bacterial membrane in terms of lipid composition with speciesstrain specific variations. The bEVs were further used to probe the interactions between bEV and antimicrobial peptides (AMPs) as model compounds by Surface Plasmon Resonance (SPR) and provide proof-of-principle that bEVs can be used as an easily accessible and highly realistic model for the bacterial surface in interaction studies. This further enables direct monitoring of the effect induced by antibiotics, or the response to host-pathogen interactions
Hormone-replacement therapy influences gene expression profiles and is associated with breast-cancer prognosis: a cohort study
BACKGROUND: Postmenopausal hormone-replacement therapy (HRT) increases breast-cancer risk. The influence of HRT on the biology of the primary tumor, however, is not well understood. METHODS: We obtained breast-cancer gene expression profiles using Affymetrix human genome U133A arrays. We examined the relationship between HRT-regulated gene profiles, tumor characteristics, and recurrence-free survival in 72 postmenopausal women. RESULTS: HRT use in patients with estrogen receptor (ER) protein positive tumors (n = 72) was associated with an altered regulation of 276 genes. Expression profiles based on these genes clustered ER-positive tumors into two molecular subclasses, one of which was associated with HRT use and had significantly better recurrence free survival despite lower ER levels. A comparison with external data suggested that gene regulation in tumors associated with HRT was negatively correlated with gene regulation induced by short-term estrogen exposure, but positively correlated with the effect of tamoxifen. CONCLUSION: Our findings suggest that post-menopausal HRT use is associated with a distinct gene expression profile related to better recurrence-free survival and lower ER protein levels. Tentatively, HRT-associated gene expression in tumors resembles the effect of tamoxifen exposure on MCF-7 cells
ÉCLAIRE - Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosytems - second periodic report 01/04/2013 to 30/09/2014
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