| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
- Cheng, Yirui, et al.
(författare)
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Comparison of serum exosome isolation methods on co-precipitated free microRNAs.
- 2020
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Ingår i: PeerJ. - : PeerJ. - 2167-8359. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: Exosomes are nano-sized extracellular vesicles containing different biomolecules such as proteins and microRNAs (miRNAs) that mediate intercellular communication. Recently, numerous studies have reported the important functions of exosomal miRNAs in disease development and the potential clinical application as diagnostic biomarkers. Up to now, the most commonly used methods to extract exosomes are ultracentrifugation (UC) and precipitation-based commercial kit (e.g., ExoQuick). Generally, both UC and ExoQuick method could co-isolate contaminating proteins along with exosomes, with the UC method yielding even purer exosomes than ExoQuick. However, the comparison of these two methods on co-precipitated free miRNAs is still unknown.Methods: In this study, we isolated exosomes from the human serum with exogenously added cel-miR-39 by UC and ExoQuick and compared the proportion of cel-miR-39 co-precipitated with exosomes extracted by these two methods.Results: Using exogenous cel-miR-39 as free miRNAs in serum, we concluded that ExoQuick co-isolates a small proportion of free miRNAs while UC hardly precipitates any free miRNAs. We also found that incubation at 37 °C for 1 h could decrease the proportion of free miRNAs, and exosomal miRNAs like miR-126 and miR-152 also decreased when RNase A was used. In conclusion, our findings provide essential information about the details of serum exosome isolation methods for further research on exosomal miRNAs.
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| 3. |
- Lárusdóttir, Marta, et al.
(författare)
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Contextual Personas : A Method for Capturing the Digital Work Environment of Users
- 2022
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Ingår i: Sense, Feel, Design. - Cham : Springer Nature. - 9783030983871 - 9783030983888 ; , s. 98-112
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Konferensbidrag (refereegranskat)abstract
- It can be hard to understand the context in which a software system is used and how the whole work environment affects the usage of a particular system. In this project, we modified the Persona method to include aspects of the digital work environment and the context to extend the understanding of these aspects during software development. The modified version of the Persona method is based on the traditional Persona method, on theories on healthy work and research on the digital work environment. The objective of proposing the modifications of the method is to give software developers more insights into the complexity of the digital work environment. University students tried the modified Contextual Persona method in a user-centred software development course. Students worked on designing a new system for 12 weeks using the Contextual Persona method during the fourth week of software development. The students gave feedback on what positive and negative aspects they experienced while using the modified Contextual Persona method and their thoughts on how the method could be improved. In the paper, we analyse reports from 30 students and summarise the feedback gathered. We conclude by summarising the possible improvements to the method based on our findings.
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| 4. |
- Waern, Annika, 1960-, et al.
(författare)
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Moving Embodied Design Education Online : Experiences from a Course in Embodied Interaction during the COVID-19 Pandemic
- 2021
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Ingår i: Extended abstracts of the 2021 CHI conference on human factors in computing systems (CHI'21). - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450380959
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Konferensbidrag (refereegranskat)abstract
- During the rapid and forced move to online teaching during the Covid-19 pandemic, university courses that never would have been considered suitable for online teaching under normal circumstances, were moved online. While challenging, this also opened opportunities for developing innovative strategies for teaching and learning. We report on the experiences of moving online a course in embodied interaction, which due to its focus on situated and embodied design faced extensive challenges in moving online. We highlight in particular the way in which the course brought forward innovative methods for bodystorming and user-assisted trialling. This paper has been written jointly by students and teachers from the course.
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