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Sensors are routinely developed for specific applications, but multipurpose sensors are challenging, due to stability and poor functional design. We report organic materials that operate in solution and gas phase. They show a strong response behaviour to at least three types of environmental changes: pH, amine and metal ion binding/detection. We have confirmed and validated our findings using various analytical and computational methods. We found that the changes in polarity of the solvent and pH not only red shift the tail of the absorption spectra, but also extend the peak optical absorption of these structures by up to 100 nm, with consequential effects on the optical gap and colour changes of the materials. Acid-base response has been studied by spectrophotometric titrations with trifluoroacetic acid (TFA) and triethyl amine (TEA). The experiments show excellent reversibility with greater sensitivity to base than acid for all compounds. Analysis into metal sensing using Zn(ii) and Cu(ii) ions as analytes show that the materials can successfully bind the cations forming stable complexes. Moreover, a strong suppression of signal with copper gives an operative modality to detect the copper ion as low as 2.5 × 10 -6 M. The formation of the metal complexes was also confirmed by growing crystals using a slow diffusion method; subsequent single crystal X-ray analysis reveals the ratio of ligand to metal to be 2 to 1. To test sensitivity towards various amine vapours, paper-based sensors have been fabricated. The sensors show a detection capability at 1 ppm of amine concentration. We have employed CIE L * a * b * colour space as the evaluation method, this provides numeric comparison of the samples from different series and allows comparison of small colour differences, which are generally undetectable by the human-eye. It shows that the CIE L * a * b * method can assess both sensitivity to a particular class of analytes and a specificity response to individual amines in this subclass offering an inexpensive and versatile methodology., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We present a global atlas of 4,728 metagenomic samples from mass-transit systems in 60 cities over 3 years, representing the first systematic, worldwide catalog of the urban microbial ecosystem. This atlas provides an annotated, geospatial profile of microbial strains, functional characteristics, antimicrobial resistance (AMR) markers, and genetic elements, including 10,928 viruses, 1,302 bacteria, 2 archaea, and 838,532 CRISPR arrays not found in reference databases. We identified 4,246 known species of urban microorganisms and a consistent set of 31 species found in 97% of samples that were distinct from human commensal organisms. Profiles of AMR genes varied widely in type and density across cities. Cities showed distinct microbial taxonomic signatures that were driven by climate and geographic differences. These results constitute a high-resolution global metagenomic atlas that enables discovery of organisms and genes, highlights potential public health and forensic applications, and provides a culture-independent view of AMR burden in cities., Competing Interests: Declaration of interests C.E.M. is co-founder of Biotia and Onegevity Health. D.B. is co-founder and CSO of Poppy Health Inc. The other authors declare they have no competing interests that impacted this study., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: The introduction of pneumococcal conjugate vaccine (PCV-7) has modified the epidemiology of invasive pneumococcal disease (IPD). Our aim was to investigate the epidemiological features of IPD before and after implementing the use of PCV-7., Methods: All invasive Streptococcus pneumoniae strains isolated in our hospital from 2000 to 2006 were included. Serotypes were identified and antibiograms were performed in all cases. Data obtained before (2000-2001) and after (2004-2006) authorization of PCV-7 use in Spain were compared., Results: There were 241 cases of IPD. None of the patients with IPD aged 2 years or younger had received PCV-7. PCV-7 coverage in children aged 5 or younger was about 48%. There was a non-significant increase in the incidence of IPD in children (from 53.8 to 57.8 cases/100 000 population), with no change in adults. When IPD incidence was adjusted by the number of blood samples collected, there was a non-significant decrease in both children and adults. Since PCV-7 came on the market, there has been a decrease in vaccine serotypes and an increase in non-vaccine serotypes. The emergent serotypes since that time include 3, 6A, 15, and 19A. Penicillin resistance decreased significantly (p<0.001) from the pre-vaccine period (87.3%) to 2003 (13.8%), and later rose from 2003 through 2006 (41.7%). Erythromycin resistance showed no changes during the study., Conclusions: The incidence of IPD in children aged 2 years and younger in Gran Canaria has not decreased despite the introduction of PCV-7. However, there has been a reduction in the number of cases related to vaccine serotypes and a significant decrease in penicillin resistance. In contrast, non-vaccine serotype IPD cases have increased. Universal vaccination and the use of new polyvalent vaccines may enhance these effects.