10 research outputs found
Nanopore DNA Sequencing and Genome Assembly on the International Space Station
We evaluated the performance of the MinION DNA sequencer in-flight on the International Space Station (ISS), and benchmarked its performance off-Earth against the MinION, Illumina MiSeq, and PacBio RS II sequencing platforms in terrestrial laboratories. Samples contained equimolar mixtures of genomic DNA from lambda bacteriophage, Escherichia coli (strain K12, MG1655) and Mus musculus (female BALB/c mouse). Nine sequencing runs were performed aboard the ISS over a 6-month period, yielding a total of 276,882 reads with no apparent decrease in performance over time. From sequence data collected aboard the ISS, we constructed directed assemblies of the ~4.6 Mb E. coli genome, ~48.5 kb lambda genome, and a representative M. musculus sequence (the ~16.3 kb mitochondrial genome), at 100%, 100%, and 96.7% consensus pairwise identity, respectively; de novo assembly of the E. coli genome from raw reads yielded a single contig comprising 99.9% of the genome at 98.6% consensus pairwise identity. Simulated real-time analyses of in-flight sequence data using an automated bioinformatic pipeline and laptop-based genomic assembly demonstrated the feasibility of sequencing analysis and microbial identification aboard the ISS. These findings illustrate the potential for sequencing applications including disease diagnosis, environmental monitoring, and elucidating the molecular basis for how organisms respond to spaceflight
Observation of CP violation in charm decays
A search for charge-parity (CP) violation in D0→K−K+ and D0→π−π+ decays is reported, using pp collision data corresponding to an integrated luminosity of 5.9 fb−1 collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D∗(2010)+→D0π+ decays or from the charge of the muon in ¯B→D0μ−¯νμX decays. The difference between the CP asymmetries in D0→K−K+ and D0→π−π+ decays is measured to be ΔACP=[−18.2±3.2(stat)±0.9(syst)]×10−4 for π-tagged and ΔACP=[−9±8(stat)±5(syst)]×10−4 for μ-tagged D0 mesons. Combining these with previous LHCb results leads to ΔACP=(−15.4±2.9)×10−4, where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of CP violation in the decay of charm hadrons
A review on recent progress in observations, sources, classification and regulations of PM2.5 in Asian environments
Natural and human activities generate a significant amount of PM2.5 (particles ≤2.5 µm in aerodynamic diameter) into the surrounding atmospheric environments. Because of their small size they can remain suspended for a relatively longer time in the air than coarse particles and thus can travel long distances in the atmosphere. PM2.5 is one of the key indicators of pollution and known to cause numerous types of respiratory and lung related diseases. Due to poor implementation of regulations and a time lag in introducing the vehicle technology, levels of PM2.5in most Asian cities are much worse than those in European environments. Dedicated reviews on understanding the characteristics of PM2.5in Asian urban environments are currently missing but much needed. In order to fill the existing gaps in the literature, the aim of this review article is to describe dominating sources and their classification, followed by current status and health impact of PM2.5, in Asian countries. Further objectives include a critical synthesis of the topics such as secondary and tertiary aerosol formation, chemical composition, monitoring and modelling methods, source apportionment, emissions and exposure impacts. The review concludes with the synthesis of regulatory guidelines and future perspectives for PM2.5 in Asian countries. A critical synthesis of literature suggests a lack of exposure and monitoring studies to inform personal exposure in the household and rural areas of Asian environments