Intestinal Taxa Abundance and Diversity in Inflammatory Bowel Disease Patients: An Analysis including Covariates and Confounders

Intestinal dysbiosis has been widely documented in inflammatory bowel diseases (IBDs) and is thought to influence the onset and perpetuation of gut inflammation. However, it remains unclear whether such bacterial changes rely in part on the modification of an IBD-associated lifestyle (e.g., smoking and physical activity) and diet (e.g., rich in dairy products, cereals, meat and vegetables). In this study, we investigated the impact of these habits, which we defined as confounders and covariates, on the modulation of intestinal taxa abundance and diversity in IBD patients. 16S rRNA gene sequence analysis was performed using genomic DNA extracted from the faecal samples of 52 patients with Crohn's disease (CD) and 58 with ulcerative colitis (UC), which are the two main types of IBD, as well as 42 healthy controls (HC). A reduced microbial diversity was documented in the IBD patients compared with the HC. Moreover, we identified specific confounders and covariates that influenced the association between some bacterial taxa and disease extent (in UC patients) or behaviour (in CD patients) compared with the HC. In particular, a PERMANOVA stepwise regression identified the variables "age", "eat yogurt at least four days per week" and "eat dairy products at least 4 days per week" as covariates when comparing the HC and patients affected by ulcerative proctitis (E1), left-sided UC (distal UC) (E2) and extensive UC (pancolitis) (E3). Instead, the variables "age", "gender", "eat meat at least four days per week" and "eat bread at least 4 days per week" were considered as covariates when comparing the HC with the CD patients affected by non-stricturing, non-penetrating (B1), stricturing (B2) and penetrating (B3) diseases. Considering such variables, our analysis indicated that the UC extent differentially modulated the abundance of the Bifidobacteriaceae, Rikenellaceae, Christensenellaceae, Marinifilaceae, Desulfovibrionaceae, Lactobacillaceae, Streptococcaceae and Peptostreptococcaceae families, while the CD behaviour influenced the abundance of Christensenellaceae, Marinifilaceae, Rikenellaceae, Ruminococcaceae, Barnesiellaceae and Coriobacteriaceae families. In conclusion, our study indicated that some covariates and confounders related to an IBD-associated lifestyle and dietary habits influenced the intestinal taxa diversity and relative abundance in the CD and UC patients compared with the HC. Indeed, such variables should be identified and excluded from the analysis to characterize the bacterial families whose abundance is directly modulated by IBD status, as well as disease extent or behaviour

Design of a novel LOX-1 receptor antagonist mimicking the natural substrate

The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), the major receptor for oxidized low-density lipoprotein (ox-LDL) in endothelial cells, is overexpressed in atherosclerotic lesions. LOX-1 specific inhibitors, urgently necessary to reduce the rate of atherosclerotic and inflammation processes, are not yet available. We have designed and synthesized a new modified oxidized phospholipid, named PLAzPC, which plays to small scale the ligand-receptor recognition scheme. Molecular docking simulations confirm that PLAzPC disables the hydrophobic component of the ox-LDL recognition domain and allows the interaction of the l-lysine backbone charged groups with the solvent and with the charged/polar residues located around the edges of the LOX-1 hydrophobic tunnel. Binding assays, in a cell model system expressing human LOX-1 receptors, confirm that PLAzPC markedly inhibits ox-LDL binding to LOX-1 with higher efficacy compared to previously identified inhibitors

Designing multiplayer games to facilitate emergent social behaviours online

This paper discusses an exploratory case study of the design of games that facilitate spontaneous social interaction and group behaviours among distributed individuals, based largely on symbolic presence 'state' changes. We present the principles guiding the design of our game environment: presence as a symbolic phenomenon, the importance of good visualization and the potential for spontaneous self-organization among groups of people. Our game environment, comprising a family of multiplayer 'bumper-car' style games, is described, followed by a discussion of lessons learned from observing users of the environment. Finally, we reconsider and extend our design principles in light of our observations

Status of the low emittance upgrade of the advanced light source

The Advanced Light Source is one of the earliest 3rd generation light sources. With an active upgrade program it has remained competitive over the years. The latest in a series of upgrades is a lattice upgrade project that was started in 2009. When it will be completed, the ALS will operate with a horizontal emittance of 2.2 nm and an effective emittance of 2.6 nm. Combined with the high current of 500 mA and the small vertical emittance the ALS already operates at, this upgrade will keep it competitive for years to come. This paper summarizes the status of the upgrade, including beam dynamics studies and lattice optimizations as well as the magnet design

Social presence and dishonesty in retail

Self-service checkouts (SCOs) in retail can benefit consumers and retailers, providing control and autonomy to shoppers independent from staff, together with reduced queuing times. Recent research indicates that the absence of staff may provide the opportunity for consumers to behave dishonestly, consistent with a perceived lack of social presence. This study examined whether a social presence in the form of various instantiations of embodied, visual, humanlike SCO interface agents had an effect on opportunistic behaviour. Using a simulated SCO scenario, participants experienced various dilemmas in which they could financially benefit themselves undeservedly. We hypothesised that a humanlike social presence integrated within the checkout screen would receive more attention and result in fewer instances of dishonesty compared to a less humanlike agent. This was partially supported by the results. The findings contribute to the theoretical framework in social presence research. We concluded that companies adopting self-service technology may consider the implementation of social presence in technology applications to support ethical consumer behaviour, but that more research is required to explore the mixed findings in the current study.<br/

Simulación de rompevórtices en el colector de entrada de un canal de ensayos

En los canales de ensayos hidrodinámicos donde la recirculación del fluido se realiza mediante una conducción de sección considerablemente inferior a la de la zona de pruebas, surge el inconveniente de la formación un chorro de alta velocidad que produce condiciones inaceptables de operación. Por lo tanto, es imperativo instalar un elemento disipador ubicado en la zona de vertido, procurando lograr condiciones de uniformidad y regularidad en el campo de velocidades en la zona de mediciones. Dicho disipador de energía cinética consiste usualmente en una serie de mallas o enrejados que actúan como promotores de vórtices de tamaño muy inferior al del chorro principal, que en virtud de sus dimensiones, se disipan rápidamente. Los fenómenos involucrados en este tipo de componente son difíciles de predecir con precisión debido fundamentalmente a las condiciones de flujo turbulento prevalecientes en las inmediaciones del mismo. Esto dificulta los cálculos, motivando la necesidad de realizar modelos computacionales con vistas a obtener criterios razonables para el diseño preliminar. En este trabajo se presenta un modelo por elementos finitos del colector de entrada de un canal de ensayos hidrodinámicos existente en la UA Mar del Plata de la Universidad Tecnológica Nacional. En el mismo, el disipador es representado por zonas donde la permeabilidad del medio se altera para simular el efecto de la presencia de las mallas difusoras. Mediante esta implementación computacional se busca obtener detalles del patrón de flujo y la incidencia del disipador en la regularización del campo de velocidades. Los resultados obtenidos son utilizados para la selección del tipo de enrejado y la cantidad de placas disipadoras necesarias para lograr que el chorro se disipe convenientemente y se alcancen condiciones uniformes en la zona de ensayos.Publicado en: Mecánica Computacional vol. XXXV, no.5Facultad de Ingenierí

Simulación de rompevórtices en el colector de entrada de un canal de ensayos

En los canales de ensayos hidrodinámicos donde la recirculación del fluido se realiza mediante una conducción de sección considerablemente inferior a la de la zona de pruebas, surge el inconveniente de la formación un chorro de alta velocidad que produce condiciones inaceptables de operación. Por lo tanto, es imperativo instalar un elemento disipador ubicado en la zona de vertido, procurando lograr condiciones de uniformidad y regularidad en el campo de velocidades en la zona de mediciones. Dicho disipador de energía cinética consiste usualmente en una serie de mallas o enrejados que actúan como promotores de vórtices de tamaño muy inferior al del chorro principal, que en virtud de sus dimensiones, se disipan rápidamente. Los fenómenos involucrados en este tipo de componente son difíciles de predecir con precisión debido fundamentalmente a las condiciones de flujo turbulento prevalecientes en las inmediaciones del mismo. Esto dificulta los cálculos, motivando la necesidad de realizar modelos computacionales con vistas a obtener criterios razonables para el diseño preliminar. En este trabajo se presenta un modelo por elementos finitos del colector de entrada de un canal de ensayos hidrodinámicos existente en la UA Mar del Plata de la Universidad Tecnológica Nacional. En el mismo, el disipador es representado por zonas donde la permeabilidad del medio se altera para simular el efecto de la presencia de las mallas difusoras. Mediante esta implementación computacional se busca obtener detalles del patrón de flujo y la incidencia del disipador en la regularización del campo de velocidades. Los resultados obtenidos son utilizados para la selección del tipo de enrejado y la cantidad de placas disipadoras necesarias para lograr que el chorro se disipe convenientemente y se alcancen condiciones uniformes en la zona de ensayos.Publicado en: Mecánica Computacional vol. XXXV, no.5Facultad de Ingenierí

Simulación de rompevórtices en el colector de entrada de un canal de ensayos

En los canales de ensayos hidrodinámicos donde la recirculación del fluido se realiza mediante una conducción de sección considerablemente inferior a la de la zona de pruebas, surge el inconveniente de la formación un chorro de alta velocidad que produce condiciones inaceptables de operación. Por lo tanto, es imperativo instalar un elemento disipador ubicado en la zona de vertido, procurando lograr condiciones de uniformidad y regularidad en el campo de velocidades en la zona de mediciones. Dicho disipador de energía cinética consiste usualmente en una serie de mallas o enrejados que actúan como promotores de vórtices de tamaño muy inferior al del chorro principal, que en virtud de sus dimensiones, se disipan rápidamente. Los fenómenos involucrados en este tipo de componente son difíciles de predecir con precisión debido fundamentalmente a las condiciones de flujo turbulento prevalecientes en las inmediaciones del mismo. Esto dificulta los cálculos, motivando la necesidad de realizar modelos computacionales con vistas a obtener criterios razonables para el diseño preliminar. En este trabajo se presenta un modelo por elementos finitos del colector de entrada de un canal de ensayos hidrodinámicos existente en la UA Mar del Plata de la Universidad Tecnológica Nacional. En el mismo, el disipador es representado por zonas donde la permeabilidad del medio se altera para simular el efecto de la presencia de las mallas difusoras. Mediante esta implementación computacional se busca obtener detalles del patrón de flujo y la incidencia del disipador en la regularización del campo de velocidades. Los resultados obtenidos son utilizados para la selección del tipo de enrejado y la cantidad de placas disipadoras necesarias para lograr que el chorro se disipe convenientemente y se alcancen condiciones uniformes en la zona de ensayos.Publicado en: Mecánica Computacional vol. XXXV, no.5Facultad de Ingenierí

Scaling Consultative Selling with Virtual Reality: Design and Evaluation of Digitally Enhanced Services

Virtual, augmented, and mixed reality technologies allow creation of powerful customer experiences and illustrative demonstrations especially in use cases that benefit from spatial visualizations. Our study focuses on the natural resource management sector and digitalizing of consultative selling process. More specifically, we look at how to improve customer engagement with the use of virtual reality (VR) and thus digitally scale consultative selling. In this process, a VR application is used to demonstrate various management operations and their economic results. Design research methodology is applied to a pre-development phase and three application development iterations between 2016 and 2018. Data consists of user interviews and video observations (N = 129) during various development iterations and three application development plans. The results show that VR offers an emotionally engaging and illustrative tool in consultative selling. Further, it opens a novel way for interaction between the salesperson and customer and possibilities to scale consultative selling digitally, emphasizing the role of trust.Peer reviewe

A process model of the formation of spatial presence experiences

In order to bridge interdisciplinary differences in Presence research and to establish connections between Presence and “older” concepts of psychology and communication, a theoretical model of the formation of Spatial Presence is proposed. It is applicable to the exposure to different media and intended to unify the existing efforts to develop a theory of Presence. The model includes assumptions about attention allocation, mental models, and involvement, and considers the role of media factors and user characteristics as well, thus incorporating much previous work. It is argued that a commonly accepted model of Spatial Presence is the only solution to secure further progress within the international, interdisciplinary and multiple-paradigm community of Presence research