| 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. |
- Pereira, Andreia, et al.
(författare)
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On the Complexity Requirements of a Panel-Based Large Intelligent Surface
- 2020
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Ingår i: 2020 IEEE Global Communications Conference, GLOBECOM 2020 - Proceedings. - 9781728182988 ; 2020-January
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Konferensbidrag (refereegranskat)abstract
- A Large Intelligent Surface (LIS) is a recently proposed concept, especially suitable for high speed indoor communications and industrial internet of things (IoT) applications. Basing the LIS on smaller panels has clear advantages in terms of flexibility and mass production of its elements. In this paper we consider a panel-based LIS and we study the interplay of the panel size, the number of baseband outputs per square meter of deployed surface, the total activated surface area, the number of baseband outputs per panel, the terminal density and the ensuing minimum terminal rate. Our performance results show that it is desirable to employ smaller panels when the terminal density increases, but this means more outputs per m2, and higher overall LIS implementation complexity. It was observed that we can surpass such increase by working with higher fractions of the LIS area. Furthermore, we present an empirical equation stating the number of outputs per panel needed to ensure that all terminals are reasonably served. These results are useful for the LIS design in practical scenarios.
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| 3. |
- Pereira, Andreia, et al.
(författare)
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The Impact of Terminal Mobility on the Performance of a Panel-Based Large Intelligent Surface
- 2020
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Ingår i: Conference Record of the 54th Asilomar Conference on Signals, Systems and Computers, ACSSC 2020. - 1058-6393. - 9780738131269 ; 2020-November, s. 569-573
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Konferensbidrag (refereegranskat)abstract
- A Large Intelligent Surface (LIS) is a recently pro-posed concept that relies on the integration of a vast number of antenna-elements over an entire surface able to transmit and/or receive information, especially suitable for high speed indoor communications and massive internet of things (IoT) applications. In this paper, we study the impact of terminal mobility on the performance of a panel-based LIS, considering different resource allocation approaches (including panel selection and/or panel-terminal association) and small panel areas. Such configuration represents a clear advantage in terms of flexibility, together with the fact that, from an economy of scale perspective, the production of this type of configuration choosing smaller areas seems more foreseeable.Our performance results show that there is no need to have a contagious distribution of panels, instead they can be physically separated according to a given distribution. It is also observed that, keeping a regularly fixed or predefined panel scheme, leading only to panel-terminal association, are able to fight against the unpredictability of terminal movements and overcome the computational complexity imposed by the optimum approach (that includes both panel selection and terminal-panel allocation stages), presenting maximum rate losses of 16-30%.
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