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[Cp*Rh] complexes (Cp* = η5-pentamethylcyclopentadienyl) supported by bidentate chelating ligands are useful in studies of redox chemistry and catalysis, but little information is available for derivatives bearing “hybrid” [P,N] chelates. Here, the preparation, structural characterization, and chemical and electrochemical properties of a [Cp*Rh] complex bearing the κ2-[P,N]-2-[(diphenylphosphino)methyl]pyridine ligand (PN) are reported. Cyclic voltammetry data reveal that [Cp*Rh(PN)Cl]PF6 (1) undergoes a chemically reversible, net two-electron reduction at -1.28 V vs. ferrocenium/ferrocene, resulting in generation of a rhodium(I) complex (3) that is stable on the timescale of the voltammetry. However, 1H and 31P{1H} NMR studies reveal that chemical reduction of 1 generates a mixture of products over a 1 h timescale; this mixture forms as a result of deprotonation of the methylene group of 1 by 3 followed by further reactivity. The analogous complex [Cp*Rh(PQN)Cl]PF6 (2; PQN = κ2-[P,N]-8-(diphenylphosphino)quinoline) does not undergo self-deprotonation or further reactivity upon two-electron reduction, confirming the reactivity of the acidic backbone methylene C-H bonds in the PN complexes. Comparison of the electrochemical properties 1 and 2 also shows that the extended conjugated system of PQN contributes to an additional ligand-centered redox event for 2 that is absent for 1.

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Microbial contamination, especially in large-scale processes, is partly a life-or-death issue for industrial fermentation. Therefore, the aim of this research was to create an antimicrobial contamination system in Bacillus subtilis 168 (an ideal acetoin producer for its safety and acetoin synthesis potential). First, introduction of the formamidase (FmdA) from Helicobacter pylori and the phosphite dehydrogenase (PtxD) from Pseudomonas stutzeri enabled the engineered Bacillus subtilis to simultaneously assimilate formamide and phosphite as nitrogen (N) and phosphorus (P) sources. Thus, the engineered B. subtilis became the dominant population in a potentially contaminated system, while contaminated microbes were starved of key nutrients. Second, stepwise metabolic engineering via chromosome-based overexpression of the relevant glycolysis and acetoin biosynthesis genes led to a 1.12-fold increment in acetoin titer compared with the starting host. Finally, with our best acetoin producer, 25.56 g/L acetoin was synthesized in the fed-batch fermentation, with a productivity of 0.33 g/L/h and a yield of 0.37 g/g under a nonsterilized and antibiotic-free system. More importantly, our work fulfills many key criteria of sustainable chemistry since sterilization is abolished, contributing to the simplified fermentation operation with lower energy consumption and cost.

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As an important industrial chemical, formaldehyde is used in various fields but is harmful to health. Developing a convenient detection device for formaldehyde is significant. Based on atomically dispersed Au on In2O3 nanosheets, a formaldehyde sensor was fabricated in this work. The highly dispersed Au obtained by the ultraviolet (UV) light-assisted reduction method helps improve the sensing performance. A meager loading amount (0.01 wt %) of Au on In2O3 nanosheets exhibits high sensitivity toward ppb-level formaldehyde. Au acts as an electron sink and promotes the oxidation of formaldehyde. Atomically dispersed Au on In2O3 nanosheets decreases the activation energy and increases the number of active sites, which result in a highly efficient conversion of formaldehyde and a marked resistance change of the fabricated sensors. The selective adsorption and oxidation of formaldehyde on single atom Au’s uniform sites establish excellent selectivity. Besides, the sensor exhibits short response/recovery time and excellent stability, with promising applications in formaldehyde detection.

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Tissue pH is tightly regulated in vivo, being a sensitive physiological biomarker. Advent of dissolution dynamic nuclear polarization (DNP) and its translation to humans stimulated development of pH-sensitive agents. However, requirements of DNP probes such as biocompatibility, signal sensitivity, and spin-lattice relaxation time (T1) complicate in vivo translation of the agents. Here, we developed a 13C-labeled alanine derivative, [1-13C]-l-alanine ethyl ester, as a viable DNP probe whose chemical shift is sensitive to the physiological pH range, and demonstrated the feasibility in phantoms and rat livers in vivo. Alanine ethyl ester readily crosses cell membrane while simultaneously assessing extracellular and intracellular pH in vivo. Following cell transport, [1-13C]-l-alanine ethyl ester is instantaneously hydrolyzed to [1-13C]-l-alanine, and subsequently metabolized to [1-13C]lactate and [13C]bicarbonate. The pH-insensitive alanine resonance was used as a reference.

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Molecular analysis of exhaled breath aerosol (EBA) with simple procedures represents a key step in clinical and point-of-care applications. Due to the crucial health role, a face mask now is a safety device that helps protect the wearer from breathing in hazardous particles such as bacteria and viruses in the air; thus exhaled breath is also blocked to congregate in the small space inside of the face mask. Therefore, direct sampling and analysis of trace constituents in EBA using a face mask can rapidly provide useful insights into human physiologic and pathological information. Herein, we introduce a simple approach to collect and analyze human EBA by combining a face mask with solid-phase microextraction (SPME) fiber. SPME fiber was inserted into a face mask to form SPME-in-mask that covered nose and mouth for in vivo sampling of EBA, and SPME fiber was then coupled with direct analysis in real-time mass spectrometry (DART-MS) to directly analyze the molecular compositions of EBA under ambient conditions. The applicability of SPME-in-mask was demonstrated by direct analysis of drugs and metabolites in oral and nasal EBA. The unique features of SPME-in-mask were also discussed. Our results showed that this method is enabled to analyze volatile and nonvolatile analytes in EBA and is expected to have a significant impact on human EBA analysis in clinical applications. We also hope this method will inspire biomarker screening of some respiratory diseases that usually required wearing of a face mask in daily life.

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Antimicrobial peptides (AMPs) are naturally occurring macromolecules made of amino acids that are potent broad-spectrum antibiotics with potential as novel therapeutic agents. This review aims to summarize the fundamental principles concerning the structure and mechanism of action of these AMPs, in order to guide the design of polymeric analogues that organic chemistry can generate. Among those simplified analogues, this review particularly focuses on those made of amino acids called polypeptide polymers: they are showing great potential by providing one of the best biomimetic and bioactive structures for further biomaterials science applications.

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In a previous experimental study, new bone was found growing within granules of HA/β-TCP. In vitro and experimental studies have shown increased protein adsorption and cell adhesion graft material bioactivated with Argon plasma. The aims of the present experiment were to study new bone ingrowth into β-TCP/HA granules used as filler material for sinus lifting and the influence on the healing of the bioactivation of the graft with argon plasma.

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Background Children with developmental coordination disorder (DCD) face significant challenges to deal with everyday activities due to underlying motor proficiency difficulties. These challenges affect children and young people’s participation; that is, involvement in daily life situations. A small body of qualitative research  has explored the experiences of children and young people with DCD from their own perspective. Therfore, understanding what it is like to live with DCD is not well conceptualised in the literature. There is a pressing need to synthesise the findings of discrete qualitative studies to advance the conceptual understanding of living with DCD, to inform health service delivery and the development and implementation of complex interventions. Aim This study aims to systematically review and synthesise qualitative literature regarding children and young people’s experiences and views of everyday life and living with DCD. Methods The method of qualitative evidence synthesis that will be followed in this review is a meta-ethnography. The eMERGe and PRISMA reporting guidelines will be adhered to. Ten databases will be searched; Academic Search Complete, AMED, CINAHL, ERIC, MEDLINE, PsychArticles, PsychInfo, EMBASE, SPORTDiscus, and Web of Science. The Joanna Briggs Institute Checklist will be used by two independent reviewers to appraise all included papers. Discussion The findings of this meta-ethnography will endeavour to inform future research, policy and practice. In particular, the results will help to inform the design of future complex interventions to meet the needs of children and young people with DCD. Dissemination will involve the publication of the results in a peer-reviewed journal. Increasingly researchers and policymakers are calling for services to be informed by the perspective and voice of children with DCD. Therefore, a policy brief will be published so that the findings are widely available. Registration: PROSPERO registration number CRD42019129178; registered on 09 July 2019.

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The use of group-based trajectory modelling (GBTM) within the medication adherence literature is rapidly growing. Researchers are adopting enhanced methods to analyse and visualise dynamic behaviours, such as medication adherence, within ‘real-world’ populations. Application of GBTM based on longitudinal adherence behaviour allows for the identification of adherence trajectories or groups.  A group is conceptually thought of a collection of individuals who follow a similar pattern of adherence behaviour over a period of time. A common obstacle faced by researchers when implementing GBTM is deciding on the number of trajectory groups that may exist within a population. Decision-making can introduce subjectivity, as there is no ‘gold standard’ for model selection criteria. This study aims to examine the extent and nature of existing evidence on the application of GBTM for medication adherence assessment, providing an overview of the different GBTM techniques used in the literature. The methodological framework will consist of five stages: i) identify the research question(s); ii) identify relevant studies; iii) select studies; iv) chart the data and finally, v) collate, summarise and report the results. Original peer-reviewed articles, published in English, describing observational and interventional studies including both concepts and/or sub-concepts of GBTM and medication adherence or any other similar terms, will be included. The following databases will be queried: PubMed/MEDLINE; Embase (Ovid); SCOPUS; ISI Web of Science and PsychInfo. This scoping review will utilise the PRISMA extension for Scoping Reviews (PRISMA-ScR) tool to report results. This scoping review will collect and schematise different techniques in the application of GBTM for medication adherence assessment available in the literature to date, identifying research and knowledge gaps in this area. This review can represent an important tool for future research, providing methodological support to researchers carrying out a group-based trajectory analysis to assess medication adherence in a real-world context.

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Background: Schistosomiasis is one of the most prevalent neglected tropical diseases (NTDs) with an estimated 229 million people requiring preventive treatment worldwide. Recommendations for preventive chemotherapy strategies have been made by the World Health Organization (WHO) whereby the frequency of treatment is determined by the settings prevalence. Despite recent progress, many countries still need to scale up treatment and important questions remain regarding optimal control strategies. This paper presents a systematic review of the economic evaluations of human schistosomiasis interventions. Methods: A systematic review of the literature was conducted on 22nd August 2019 using the PubMed (MEDLINE) and ISI Web of Science electronic databases. The focus was economic evaluations of schistosomiasis interventions, such as cost-effectiveness and cost-benefit analyses. No date or language stipulations were applied to the searches. Results: We identified 53 relevant health economic analyses of schistosomiasis interventions. Most studies related to Schistosoma japonicum followed by S. haematobium. Several studies also included other NTDs. In Africa, most studies evaluated preventive chemotherapy, whereas in China they mostly evaluated programmes using a combination of interventions (such as chemotherapy, snail control and health education). There was wide variation in the methodology and epidemiological settings investigated. A range of effectiveness metrics were used by the different studies. Conclusions: Due to the variation across the identified studies, it was not possible to make definitive policy recommendations. Although, in general, the current WHO recommended preventive chemotherapy approach to control schistosomiasis was found to be cost-effective. This finding has important implications for policymakers, advocacy groups and potential funders. However, there are several important inconsistencies and research gaps (such as how the health benefits of interventions are quantified) that need to be addressed to identify the resources required to achieve schistosomiasis control and elimination.