Additive manufacturing (also known as three-dimensional (3D) printing) is being extensively utilized in many areas of electrochemistry to produce electrodes and devices, as this technique allows for ...fast prototyping and is relatively low cost. Furthermore, there is a variety of 3D-printing technologies available, which include fused deposition modeling (FDM), inkjet printing, select laser melting (SLM), and stereolithography (SLA), making additive manufacturing a highly desirable technique for electrochemical purposes. In particular, over the last number of years, a significant amount of research into using 3D printing to create electrodes/devices for electrochemical energy conversion and storage has emerged. Strides have been made in this area; however, there are still a number of challenges and drawbacks that need to be overcome in order to 3D print active and stable electrodes/devices for electrochemical energy conversion and storage to rival that of the state-of-the-art. In this Review, we will give an overview of the reasoning behind using 3D printing for these electrochemical applications. We will then discuss how the electrochemical performance of the electrodes/devices are affected by the various 3D-printing technologies and by manipulating the 3D-printed electrodes by post modification techniques. Finally, we will give our insights into the future perspectives of this exciting field based on our discussion through this Review.
Summary
The discovery of host‐encoded gene products that sense molecular patterns in infectious microbes, and the demonstration of their role in triggering innate and adaptive immune responses, has ...been a key milestone in our understanding of immunology. Twenty‐three years after Janeway first outlined the fundamental concepts of the ‘pattern recognition’ model, and 15 years since the identification of Toll‐like receptors (TLRs) as pattern recognition receptors (PRRs), new insights continue to be revealed, and questions remain. For example, innate immune responses to microbes that are mediated by PRRs have historically been viewed as the domain of innate immune cell populations such as dendritic cells and macrophages. New evidence, however, has pointed to the role of B‐cell‐intrinsic TLR activation in shaping antibody responses. These studies have revealed that TLRs regulate a complex transcriptional network that controls multiple steps in the development of antigen‐specific antibodies. This review covers these recent developments regarding the role of TLRs in B‐cell gene expression and function in vitro and in vivo, and highlights the remaining challenges in the field, with particular emphasis on the role of TLRs in antibody responses to viral infection. A more complete understanding of how TLRs regulate antibody responses will lead to improved vaccine design.
3D-printing (or additive manufacturing) is presently an emerging technology that promises to reshape traditional manufacturing processes. The electrochemistry field can certainly take advantage of ...this fabrication tool for sensing and energy-related applications. Polymer/graphene filaments commonly used for the fabrication of 3D-printed electrodes show poor electrochemistry in the native state, requiring post-fabrication activation procedures. In the present work, solvent activation of graphene/polymer-based 3D-printed electrodes was investigated, using both polar aprotic solvents (DMF and acetone) and polar protic solvents (EtOH, MeOH, and H2O). Differences were noted with respect to the weight loss and surface morphologies of the activated electrodes prior to their use, depending the solvent used. The electrodes activated in polar aprotic solvents exhibit a dramatic increase in heterogeneous electron transfer rate using the Fe(CN6)4−/3− redox couple. Moreover, the activation medium has a crucial influence on the electrochemical double layer. We wish to provide meaningful insight to researchers by comparing results obtained with 3D-printed electrodes fabricated from graphene/polymer filaments and drawing attention to the influence of the solvents used in their activation.
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•Cheap and quick 3D printing and activation of 3D Printed Graphene/PLA electrodes.•Solvent activation improves the capacitance and electron transfer properties.•Polar aprotic solvents have better activation capabilities than polar protic solvents.
Our intestinal microbiota harbours a diverse bacterial community required for our health, sustenance and wellbeing. Intestinal colonization begins at birth and climaxes with the acquisition of two ...dominant groups of strict anaerobic bacteria belonging to the Firmicutes and Bacteroidetes phyla. Culture-independent, genomic approaches have transformed our understanding of the role of the human microbiome in health and many diseases. However, owing to the prevailing perception that our indigenous bacteria are largely recalcitrant to culture, many of their functions and phenotypes remain unknown. Here we describe a novel workflow based on targeted phenotypic culturing linked to large-scale whole-genome sequencing, phylogenetic analysis and computational modelling that demonstrates that a substantial proportion of the intestinal bacteria are culturable. Applying this approach to healthy individuals, we isolated 137 bacterial species from characterized and candidate novel families, genera and species that were archived as pure cultures. Whole-genome and metagenomic sequencing, combined with computational and phenotypic analysis, suggests that at least 50-60% of the bacterial genera from the intestinal microbiota of a healthy individual produce resilient spores, specialized for host-to-host transmission. Our approach unlocks the human intestinal microbiota for phenotypic analysis and reveals how a marked proportion of oxygen-sensitive intestinal bacteria can be transmitted between individuals, affecting microbiota heritability.
Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike ...pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria.
Purpose To assess the impact of providing healthcare professionals with feedback on patient-reported outcome measures (PROMs). Methods This is a systematic review including controlled studies ...investigating the effectiveness of PROMs feedback, specifically examining the impact at a group-level and a patient-level. Results Only one study provided feedback at a group-level as a measure of professional performance, which found no intervention effect. At a patient-level, sixteen studies were identified and only one study found an overall significant difference in the PROM score. However, an additional six studies found a significant result favouring the intervention group for a particular subgroup or domain. The studies which demonstrated the greatest impact primarily used PROMs as a management tool in an outpatient setting on a specialised patient population. In contrast, there was weak evidence supporting with the use of PROMs as a screening tool. The studies which found a positive effect had a lower quality score on average. Conclusions The effectiveness of PROMs feedback seems to be related to the function of the PROM. However, the evidence regarding the impact of PROMs feedback on patient outcomes is weak, and methodological issues with studies are frequent. The use of PROMs as a performance measure is not well investigated. Future research should focus on the appropriate application of PROMs by testing specific hypothesis related to cause and effect. Qualitative research is required to provide a deeper understanding of the practical issues surrounding the implementation of PROMs and the methodological issues associated with the effective use of the information.
Toll-like receptors (TLRs) are key pathogen sensing receptors that respond to diverse microbial ligands, and trigger both innate and adaptive immune responses to infection. Since their discovery, a ...growing body of evidence has pointed to an important role for TLRs in retroviral infection and pathogenesis. These data suggest that multiple TLRs contribute to the anti-retroviral response, and that TLR engagement by retroviruses can have complex and divergent outcomes for infection. Despite this progress, numerous questions remain about the role of TLRs in retroviral infection. In this review, I summarize existing evidence for TLR-retrovirus interactions and the functional roles these receptors play in immunity and pathogenesis, with particular focus on human immunodeficiency virus (HIV).
We introduce a mixture of generalized hyperbolic distributions as an alternative to the ubiquitous mixture of Gaussian distributions as well as their near relatives within which the mixture of ...multivariate t-distributions and the mixture of skew-t distributions predominate. The mathematical development of our mixture of generalized hyperbolic distributions model relies on its relationship with the generalized inverse Gaussian distribution. The latter is reviewed before our mixture models are presented along with details of the aforesaid reliance. Parameter estimation is outlined within the expectation-maximization framework before the clustering performance of our mixture models is illustrated via applications on simulated and real data. In particular, the ability of our models to recover parameters for data from underlying Gaussian and skew-t distributions is demonstrated. Finally, the role of generalized hyperbolic mixtures within the wider model-based clustering, classification, and density estimation literature is discussed. Les auteurs présentent un mélange de distributions hyperboliques généralisées comme solution de rechange aux mélanges habituels basés sur la distribution gaussienne, celle de Student ou celle de Student asymétrique. Les auteurs passent en revue les propriétés de l'inverse généralisé de la distribution gaussienne puisque le développement mathématique qu'ils présentent repose sur un lien, présenté en détail, entre cet inverse généralisé et les distributions hyperboliques généralisées. Ils procèdent à l'estimation des paramètres par un algorithme d'espérance-maximisation, puis ils illustrent la performance de leur modèle dans le cadre d'une analyse de regroupement en l'appliquant à des données simulées, ainsi qu'à un jeu de données réelles. Les auteurs démontrent la capacité de leur modèle à récupérer les paramètres des distributions sous-jacentes lorsque celles-ci sont gaussiennes, ou lorsqu'elles suivent une loi de Student asymétrique. Finalement, ils discutent le rôle de la distribution hyperbolique généralisée lorsqu'un modèle est utilisé pour l'analyse de regroupement, la classification ou l'estimation de la densité.
Currently, bacterial 16S rRNA gene analyses are based on sequencing of individual variable regions of the 16S rRNA gene (Kozich, et al Appl Environ Microbiol 79:5112-5120, 2013).This short read ...approach can introduce biases. Thus, full-length bacterial 16S rRNA gene sequencing is needed to reduced biases. A new alternative for full-length bacterial 16S rRNA gene sequencing is offered by PacBio single molecule, real-time (SMRT) technology. The aim of our study was to validate PacBio P6 sequencing chemistry using three approaches: 1) sequencing the full-length bacterial 16S rRNA gene from a single bacterial species Staphylococcus aureus to analyze error modes and to optimize the bioinformatics pipeline; 2) sequencing the full-length bacterial 16S rRNA gene from a pool of 50 different bacterial colonies from human stool samples to compare with full-length bacterial 16S rRNA capillary sequence; and 3) sequencing the full-length bacterial 16S rRNA genes from 11 vaginal microbiome samples and compare with in silico selected bacterial 16S rRNA V1V2 gene region and with bacterial 16S rRNA V1V2 gene regions sequenced using the Illumina MiSeq.
Our optimized bioinformatics pipeline for PacBio sequence analysis was able to achieve an error rate of 0.007% on the Staphylococcus aureus full-length 16S rRNA gene. Capillary sequencing of the full-length bacterial 16S rRNA gene from the pool of 50 colonies from stool identified 40 bacterial species of which up to 80% could be identified by PacBio full-length bacterial 16S rRNA gene sequencing. Analysis of the human vaginal microbiome using the bacterial 16S rRNA V1V2 gene region on MiSeq generated 129 operational taxonomic units (OTUs) from which 70 species could be identified. For the PacBio, 36,000 sequences from over 58,000 raw reads could be assigned to a barcode, and the in silico selected bacterial 16S rRNA V1V2 gene region generated 154 OTUs grouped into 63 species, of which 62% were shared with the MiSeq dataset. The PacBio full-length bacterial 16S rRNA gene datasets generated 261 OTUs, which were grouped into 52 species, of which 54% were shared with the MiSeq dataset. Alpha diversity index reported a higher diversity in the MiSeq dataset.
The PacBio sequencing error rate is now in the same range of the previously widely used Roche 454 sequencing platform and current MiSeq platform. Species-level microbiome analysis revealed some inconsistencies between the full-length bacterial 16S rRNA gene capillary sequencing and PacBio sequencing.
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