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  1. This study evaluates the beneficial effects of discharging nanosecond pulse transient plasma (NPTP) in a coaxial electrostatic precipitator for capturing nanoscale soot particles (∼50 nm) produced by an ethylene flame. 
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    Free, publicly-accessible full text available October 30, 2024
  2. Abstract

    Most bacteria in the biosphere are predicted to be polylysogens harbouring multiple prophages1–5. In studied systems, prophage induction from lysogeny to lysis is near-universally driven by DNA-damaging agents6. Thus, how co-residing prophages compete for cell resources if they respond to an identical trigger is unknown. Here we discover regulatory modules that control prophage induction independently of the DNA-damage cue. The modules bear little resemblance at the sequence level but share a regulatory logic by having a transcription factor that activates the expression of a neighbouring gene that encodes a small protein. The small protein inactivates the master repressor of lysis, which leads to induction. Polylysogens that harbour two prophages exposed to DNA damage release mixed populations of phages. Single-cell analyses reveal that this blend is a consequence of discrete subsets of cells producing one, the other or both phages. By contrast, induction through the DNA-damage-independent module results in cells producing only the phage sensitive to that specific cue. Thus, in the polylysogens tested, the stimulus used to induce lysis determines phage productivity. Considering the lack of potent DNA-damaging agents in natural habitats, additional phage-encoded sensory pathways to lysis likely have fundamental roles in phage–host biology and inter-prophage competition.

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    Free, publicly-accessible full text available August 17, 2024
  3. Optical coatings play a vital role in sensing technologies. The development of new coatings that exhibit minimal optical losses requires a detailed understanding of the development of defects within them. Current methods of defect characterization involve direct microscope imaging or x-ray diffraction studies in the case of crystallites. In this paper, we demonstrate the characterization of coating defects using light scattering, which can yield information about their size, location, and index of refraction. The method requires measuring the scattered power of each individual defect as a function of angle and comparing the data with theoretical models. Finally, we argue that this method can be used for the determination of the defect location within a multi-layer stack.

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  4. Abstract

    The ability to profile transcriptomes and characterize global gene expression changes has been greatly enabled by the development of RNA sequencing technologies (RNA-seq). However, the process of generating sequencing-compatible cDNA libraries from RNA samples can be time-consuming and expensive, especially for bacterial mRNAs which lack poly(A)-tails that are often used to streamline this process for eukaryotic samples. Compared to the increasing throughput and decreasing cost of sequencing, library preparation has had limited advances. Here, we describe bacterial-multiplexed-seq (BaM-seq), an approach that enables simple barcoding of many bacterial RNA samples that decreases the time and cost of library preparation. We also present targeted-bacterial-multiplexed-seq (TBaM-seq) that allows for differential expression analysis of specific gene panels with over 100-fold enrichment in read coverage. In addition, we introduce the concept of transcriptome redistribution based on TBaM-seq that dramatically reduces the required sequencing depth while still allowing for quantification of both highly and lowly abundant transcripts. These methods accurately measure gene expression changes with high technical reproducibility and agreement with gold standard, lower throughput approaches. Together, use of these library preparation protocols allows for fast, affordable generation of sequencing libraries.

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