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Background: Immersive virtual reality (VR) is increasingly used in organizational training interventions. However, few studies have systematically investigated VR compared to standard training methods in actual organizational contexts. Objectives: The focus of this study was to evaluate the effectiveness of a VR simulation for training professionals in the biotech industry. Aligning training needs to unique media affordances, the study designed an immersive story-based VR simulation for training customer-facing employees on a new product and tested it in an international biotech company. Methods: The system was evaluated by comparing its effectiveness to a traditional video presentation with the same content in a randomized between subjects experiment. The sample consisted of 95 employees across three locations: Brazil, Denmark, and USA. Results: The VR simulation group performed better than the video presentation group on the outcomes of conceptual knowledge (d = 0.41) spatial knowledge (d = 0.61), transfer intentions (d = 0.57), enjoyment (d = 1.74), self-efficacy (d = 0.68), perceived learning (d = 0.89), personal value (d = 0.83), and organizational value (d = 0.82), but no significant difference was found for factual knowledge (d = -0.10). Implications: Results suggest that VR simulations can be effective across cultures in organizational training interventions. VR is specifically effective when the goals of the training are to increase conceptual and spatial understanding as well as enjoyment, and self-efficacy, but not factual knowledge. Furthermore, employees report higher levels of perceived learning, personal and organizational value and transfer intentions after VR training compared to standard video-based training.

Background: Immersive virtual reality (VR) is increasingly used in organizational training interventions. However, few studies have systematically investigated VR compared to standard training methods in actual organizational contexts. Objectives: The focus of this study was to evaluate the effectiveness of a VR simulation for training professionals in the biotech industry. Aligning training needs to unique media affordances, the study designed an immersive story‐based VR simulation for training customer‐facing employees on a new product and tested it in an international biotech company. Methods: The system was evaluated by comparing its effectiveness to a traditional video presentation with the same content in a randomized between subjects experiment. The sample consisted of 95 employees across three locations: Brazil, Denmark, and USA. Results: The VR simulation group performed better than the video presentation group on the outcomes of conceptual knowledge (d = 0.41) spatial knowledge (d = 0.61), transfer intentions (d = 0.57), enjoyment (d = 1.74), self‐efficacy (d = 0.68), perceived learning (d = 0.89), personal value (d = 0.83), and organizational value (d = 0.82), but no significant difference was found for factual knowledge (d = −0.10). Implications: Results suggest that VR simulations can be effective across cultures in organizational training interventions. VR is specifically effective when the goals of the training are to increase conceptual and spatial understanding as well as enjoyment, and self‐efficacy, but not factual knowledge. Furthermore, employees report higher levels of perceived learning, personal and organizational value and transfer intentions after VR training compared to standard video‐based training. Lay Description: What is currently known about the subject matter: Immersive virtual reality (VR) is increasingly used in organizational training interventions. This interest has especially surged amid recent global challenges, and the sudden need for companies and employees to adapt to the new remote working conditions.However, few studies have systematically investigated VR compared to standard training methods in actual organizational contexts that include a real‐world scenario and a representative testing sample.Applied research that assesses the outcomes of VR based training in realistic learning and training settings is needed. What their paper adds: We propose and test an interdisciplinary approach that links unique features of VR with training needs and multidimensional outcome measures in an organizational training context within the biotech industry in Brazil, Denmark and USA.The findings suggest that a specifically designed VR tool is superior to a comparable video presentation for the outcomes of spatial and conceptual knowledge acquisition and transfer intentions, but not factual knowledge acquisition.The VR group also reported significantly higher personal value, organizational value, self‐efficacy, perceived learning, and enjoyment compared to the video group. Implications of study findings for practitioners: The results support the value of using VR simulations in organizational training, specifically related to affective outcomes as well as spatial and conceptual knowledge and transfer intentions.The study suggests that it is not the medium of VR, but rather the alignment between the training goals with the instructional methods and the unique affordances of VR that will contribute to better or worse learning outcomes.The article describes how to evaluate the effectiveness of VR tools in applied contexts, suggesting that we have to evaluate the effectiveness of tested content with respect to different outcome variables, which coincide with the training outcomes of a particular organizational context.The project as a whole, can be used as a blueprint for future applied research efforts, exemplifying how to bridge gaps between small‐medium‐enterprises, international corporate companies and academic institutions. [ABSTRACT FROM AUTHOR]

During Pseudomonas aeruginosa flow cell biofilm development, the cell population differentiates into a nonmotile subpopulation which forms microcolonies and a migrating subpopulation which eventually colonizes the top of the microcolonies, resulting in the development of mushroom-shaped multicellular structures. The cap-forming subpopulation was found to develop tolerance to membrane-targeting antimicrobial agents, such as the cyclic cationic peptide colistin and the detergent sodium dodecyl sulfate. The stalk-forming subpopulation, on the other hand, was sensitive to the membrane-targeting antibacterial agents. All biofilm-associated cells were sensitive to the antibacterial agents when tested in standard plate assays. A mutation eliminating the production of type IV pili, and hence surface-associated motility, prevented the formation of regular mushroom-shaped structures in the flow cell biofilms, and the development of tolerance to the antimicrobial agents was found to be affected as well. Mutations in genes interfering with lipopolysaccharide modification (pmr) eliminated the biofilm-associated colistin tolerance phenotype. Experiments with a PAO1 strain harboring a pmr-gfp fusion showed that only the cap-forming subpopulation in biofilms treated with colistin expresses the pmr operon. These results suggest that increased antibiotic tolerance in biofilms may be a consequence of differentiation into distinct subpopulations with different phenotypic properties.

Muramidases constitute a superfamily of enzymes that hydrolyse peptidoglycan (PGN) from bacterial cell walls. Recently, a fungal muramidase derived from Acremonium alcalophilum has been shown to increase broiler performance when added as a feed additive. However, the underlying mechanisms of action are not yet identified. Here, we investigated the hypothesis that this muramidase can cleave PGN to muramyl dipeptide (MDP), activating nucleotide-binding oligomerisation domain-containing protein 2 (NOD2) receptors in eukaryotic cells, potentially inducing anti-inflammatory host responses. Using Micrococcus luteus as a test bacterium, it was shown that muramidase from A. alcalophilum did not display antimicrobial activity, while it could cleave fluorescently labelled PGN. It was shown that the muramidase could degrade PGN down to its minimal bioactive structure MDP by using UPLC-MS/MS. Using HEK-Blue™-hNOD2 reporter cells, it was shown that the muramidase-treated PGN degradation mixture could activate NOD2. Muramidase supplementation to broiler feed increased the duodenal goblet cell and intraepithelial lymphocyte abundance while reducing duodenal wall CD3+ T lymphocyte levels. Muramidase supplementation to broiler feed only had moderate effects on the duodenal, ileal and caecal microbiome. It was shown that the newly discovered muramidase hydrolysed PGN, resulting in MDP that activates NOD2, potentially steering the host response for improved intestinal health. [ABSTRACT FROM AUTHOR]

This study evaluates peptidoglycan hydrolysis by amicrobialmuramidase from the fungus Acremonium alcalophilum in vitro and in the gastrointestinal tract of broiler chickens. Peptidoglycan used for in vitro studies was derived from 5 gram-positive chicken gut isolate type strains. In vitro peptidoglycan hydrolysis was studied by three approaches: (a) helium ion microscopy to identify visual phenotypes of hydrolysis, (b) reducing end assay to quantify solubilization of peptidoglycan fragments, and (c) mass spectroscopy to estimate relative abundances of soluble substrates and reaction products. Visual effects of peptidoglycan hydrolysis could be observed by helium ion microscopy and the increase in abundance of soluble peptidoglycan due to hydrolysis was quantified by a reducing end assay. Mass spectroscopy confirmed the release of hydrolysis products and identified muropeptides from the five different peptidoglycan sources. Peptidoglycan hydrolysis in chicken crop, jejunum, and caecum samples was measured by quantifying the total and solublemuramic acid content. A significant increase in the proportion of the solublemuramic acid was observed in all three segments upon inclusion of the microbial muramidase in the diet. [ABSTRACT FROM AUTHOR]

Context. microRNA (miRNA) expression profiling and classification of tissue obtained from fine-needle aspirates (FNA) could be a major improvement of the preoperative diagnosis of thyroid nodules. Objective. Before this can be clinically implemented, a robust and non-toxic method for obtaining sufficient quantity and quality of RNA from single in vivo FNA has to be established. RNA later is a non-toxic RNA-stabilizing agent. However, due to the high density of RNA later, pelleting of the tissue samples is difficult, and results in low recovery of RNA that is insufficient for subsequent miRNA array expression analysis. We therefore developed a simple centrifugation method for capturing tissue stored in RNA later on a 0.45-μm filter. Design. FNA from 24 patients with a solitary cold thyroid nodule was stored in Trizol, liquid nitrogen, or RNA later. The tissue stored in RNA later was either pelleted by centrifugation or captured on the 0.45-μm filters. RNA was extracted using the Trizol method. To validate results, FNA from additional 30 patients were analyzed based on the modified RNA later protocol. Main outcome. Capturing FNA tissue samples on the filters increased the RNA yield 10 fold and maintained RNA purity, permitting miRNA array expression profiling and allowing comparable levels of known miRNA-clusters regardless of preservation technique. Results were confirmed in an additional 30 patients. Conclusion. The modified RNA later protocol is well suited for isolating RNA from single thyroid in vivo FNA in a clinical setting. Furthermore this permits shipping of FNA samples at room temperature from peripheral centers to a centralized array core facility. [ABSTRACT FROM AUTHOR]

Surface-associated microbial communities in many cases display dynamic developmental patterns. Model biofilms formed by Pseudomonas aeruginosa and Pseudomonas putida in laboratory flow-chamber setups represent examples of such behaviour. Dependent on the experimental conditions the bacteria in these model biofilms develop characteristic multicellular structures through a series of distinct steps where cellular migration plays an important role. Despite the appearance of these characteristic developmental patterns in the model biofilms the available evidence suggest that the biofilm forming organisms do not possess comprehensive genetic programs for biofilm development. Instead the bacteria appear to have evolved a number of different mechanisms to optimize surface colonization, of which they express a subset in response to the prevailing environmental conditions. These mechanisms include the ability to regulate cellular adhesiveness and migration in response to micro-environmental signals including those secreted by the bacteria themselves. [ABSTRACT FROM AUTHOR]

Virulence ofPseudomonas aeruginosainvolves the co-ordinate expression of a range of factors including type IV pili (tfp), the type III secretion system (TTSS) and quorum sensing. Tfp are required for twitching motility, efficient biofilm formation, and for adhesion and type III secretion (TTS)-mediated damage to mammalian cells. We describe a novel gene (fimL) that is required for tfp biogenesis and function, for TTS and for normal biofilm development inP. aeruginosa. The predicted product offimLis homologous to the N-terminal domain of ChpA, except that its putative histidine and threonine phosphotransfer sites have been replaced with glutamine.fimLmutants resemblevfrmutants in many aspects including increased autolysis, reduced levels of surface-assembled tfp and diminished production of type III secreted effectors. Expression ofvfr in transcan complementfimLmutants.vfrtranscription and production is reduced infimLmutants whereas cAMP levels are unaffected. Deletion and insertion mutants offimLfrequently revert to wild-type phenotypes suggesting that an extragenic suppressor mutation is able to overcome the loss offimL.vfrtranscription and production, as well as cAMP levels, are elevated in these revertants, whilePseudomonasquinolone signal (PQS) production is reduced. These results suggest that the site(s) of spontaneous mutation is in a gene(s) which lies upstream ofvfrtranscription, cAMP, production, and PQS synthesis. Our studies indicate that Vfr and FimL are components of intersecting pathways that control twitching motility, TTSS and autolysis inP. aeruginosa. [ABSTRACT FROM AUTHOR]

Bacterial debris in the gastrointestinal tract (GIT) are continuously being produced by the microbiota present upon bacterial division and death. One of the most abundant components in bacterial debris are peptidoglycans (PGN), a structural cell wall component in gram-positive and negative bacteria. The objective of this work was to investigate if addition of a novel microbial muramidase (Muramidase 007; MUR) that hydrolyzes PGN, would reduce PGN adhesion to porcine intestinal cells in-vitro and hydrolyze PGN in the GIT of swine. Adhesion efficacy of intact and MUR hydrolyzed fluorescein-isothiocyanate (FITC)-labelled PGN were compared using fluorescence-microscopy (3 wells/condition). Catalytic performance of MUR on intact FITC-labelled PGN adhered to intestinal cells were also tested. In-vivo MUR-supplementation at 50,000 LSU/kg diet to gestating and lactating sows and/or their subsequent offspring for 42-d post-weaning was investigated. Mass-spectroscopy was used to quantify soluble and total muramic acid, which is only found in PGN, in the ileal and cecal digesta (8 piglets/treatment) to calculate percentage soluble-PGN. Cell-culture data were analyzed using GraphPad-Prism 8.0 and in-vivo data using mixedmodels in JMP 14.0. MUR hydrolyzed PGN adhered 10x less to the IPEC-J2 cell line culture compared to intact-PGN (P< 0.05). In addition, data show that MUR hydrolyzed PGN attached to cell surfaces by 2x, as attached PGN were also reduced by 50% following MUR incubation (P< 0.05). Offering sows MUR-diets had no carryover effect on the percentage soluble PGN in their piglets' digesta, and there were no interactions observed for sow x piglet x tract neither (P >0.05). Percentage soluble-PGN increased in piglets fed MUR compared to control-piglets (47.18 vs. 29.84% SEM:1.624; P< 0.001) and was higher in cecal digesta compared to ileal digesta (49.91 vs. 27.11%; SEM:1.634; P< 0.001), irrespective of MUR-supplementation. These results suggest that MUR may reduce PGN adhesion to intestinal cells and may hydrolyze PGN found in the GIT. [ABSTRACT FROM AUTHOR]