| 1. |
- Beal, Jacob, et al.
(författare)
-
Robust estimation of bacterial cell count from optical density
- 2020
-
Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
-
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.
|
|
| 2. |
- Zeng, Jiangyuan, et al.
(författare)
-
Innovations in science, technology, engineering, and policy (iSTEP) for addressing environmental issues towards sustainable development
- 2024
-
Ingår i: The Innovation Geoscience. - : Innovation Press. - 2959-8753. ; 2:3
-
Tidskriftsartikel (refereegranskat)abstract
- Sustainable development depends on the integration of the economy, society, and environment. Yet, escalating environmental challenges pose threats to both society and the economy. Despite progress in addressing environmental issues to promote sustainability, knowledge gaps in scientific research, technological advancement, engineering practice, and policy development persist. In this review, we aim to narrow these gaps by proposing innovation-based solutions and refining existing paradigms. Reviewing past research and actions, we first elucidate the evolution of sustainability science and the essence of sustainable development and its assessment. Secondly, we summarize current major environmental issues, including global warming and climate change, biodiversity loss, land degradation and desertification, and environmental pollution, as well as their relationships with sustainability and the achievement of Sustainable Development Goals (SDGs). Subsequently, this review critically evaluates the role of innovations in science, technology, engineering, and policy (iSTEP) and their synergies in advancing sustainability and SDGs. While their sequential relationships may vary based on specific contexts or sustainability scenarios within the iSTEP framework, each component reinforces the others, fostering continuous improvement. Finally, this review offers recommendations and future perspectives for formulating sustainability roadmaps. Recommendations include fostering a vision of sustainability, promoting interdisciplinary collaboration, and encouraging transboundary cooperation among stakeholders for future sustainability endeavors.
|
|
| 3. |
- Jiang, Liang, et al.
(författare)
-
Formation of Spinel Phases in Oxidized BOF Slag under Different Cooling Conditions
- 2017
-
Ingår i: Steel Research International. - : John Wiley & Sons. - 1611-3683 .- 1869-344X. ; 88:11
-
Tidskriftsartikel (refereegranskat)abstract
- To enhance utilization of wastes generated from steelmaking, a BOF slag sample from Ning Steel group in China is treated by oxidizing at 1500 °C for 30 min and then cooled by different methods. The treated samples are characterized, in combination with calculations using FactSage 6.4. XRD results show that iron oxides in BOF slag are converted largely by the oxidation to spinel phases, Fe3O4 and MgFe2O4, which also eliminates free CaO and MgO. EDS analyses show Fe element existing in di-calcium silicate and glass phase, which are Fe3+ ions formed by oxidation. An incorporation of Fe3+ ions into crystal structures has stabilized high temperature polymorph of C2S, β-C2S, and α’-C2S, in the treated slag samples. Fe3+ ions may also act as a network former to facilitate glass formation. This may make it possible for the glass and α’-C2S phase to complement each other, leading to a higher hydraulicity, while the BOF slag, after the spinel separation, is blended in cements. Some suggestions are proposed, based on the present and early studies, to enhance hydraulicity for the BOF slag, as well as grain sizes of spinel phases, which may result in economic and environmental benefits for steel and cement industries.
|
|
