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Skin uses interdependent cellular networks for barrier integrity and host immunity, but most underlying mechanisms remain obscure. Herein, we demonstrate that the human parasitic helminth Schistosoma mansoniinhibited pruritus evoked by itch-sensing afferents bearing the Mas-related G-protein-coupled receptor A3 (MrgprA3) in mice. MrgprA3 neurons controlled interleukin (IL)-17+γδ T cell expansion, epidermal hyperplasia and host resistance against S. mansonithrough shaping cytokine expression in cutaneous antigen-presenting cells. MrgprA3 neuron activation downregulated IL-33 but induced IL-1β and tumor necrosis factor in macrophages and type 2 conventional dendritic cells partially through the neuropeptide calcitonin gene-related peptide. Macrophages exposed to MrgprA3-derived secretions or bearing cell-intrinsic IL-33 deletion showed increased chromatin accessibility at multiple inflammatory cytokine loci, promoting IL-17/IL-23-dependent changes to the epidermis and anti-helminth resistance. This study reveals a previously unrecognized intercellular communication mechanism wherein itch-inducing MrgprA3 neurons initiate host immunity against skin-invasive parasites by directing cytokine expression patterns in myeloid antigen-presenting cell subsets.

IL-33 is an IL-1 family cytokine that signals through its cognate receptor, ST2, to regulate inflammation. Whether IL-33 serves a pathogenic or protective role during inflammatory bowel disease is controversial. Herein, two different strains of cell-specific conditionally deficient mice were used to compare the role of myeloid- versus intestinal epithelial cell–derived IL-33 during dextran sodium sulfate–induced colitis. Data show that loss of CD11c-restricted IL-33 exacerbated tissue pathology, coinciding with increased tissue Il6levels and loss of intestinal forkhead box p3+regulatory T cells. Surprisingly, the lack of intestinal epithelial cell–derived IL-33 had no impact on disease severity or tissue recovery. Thus, we show that myeloid-derived IL-33 functionally restrains colitic disease, whereas intestinal epithelial cell–derived IL-33 is dispensable.

Host defense at the mucosal interface requires collaborative interactions between diverse cell lineages. Epithelial cells damaged by microbial invaders release reparative proteins such as the Trefoil factor family (TFF) peptides that functionally restore barrier integrity. However, whether TFF peptides and their receptors also serve instructive roles for immune cell function during infection is incompletely understood. Here, we demonstrate that the intestinal trefoil factor, TFF3, restrains TH1 cell proliferation and promotes host protective Type 2 immunity against the gastrointestinal parasitic nematode Trichuris muris.Accordingly, T cell-specific deletion of the TFF3 receptor, Lingo2, impairs TH2 cell commitment, allows proliferative expansion of IFNγ+CD4+TH1 cells and blocks normal worm expulsion through an IFNγ-dependent mechanism. This study indicates that TFF3, in addition to its known tissue reparative functions, drives anti-helminth immunity by controlling the balance between TH1/TH2 subsets.

Abstract:This paper examines the American sojourn of the Enlightenment philosopher and theologian George Berkeley. While living in coastal Rhode Island between 1729 and 1731, Berkeley penned his longest philosophical tract, Alciphron: Or, the Minute Philosopher (1732), which criticized “freethinking,” mechanical conceptions of nature in favor of those that emphasized God's providence. To illustrate these two ways of knowing nature, Berkeley, a careful prose stylist, evoked nearby coastal landscapes for contrast. Accordingly, his work broke down dichotomies between ideas and matter and, by extension, culture and nature, which could, this paper argues, inform an environmental ethic for a “hybrid” world.

Abstract: For several decades researchers have been interested in textile processes for the production of composite reinforcement. These technologies have offered several promises: reduced fabrication costs, 3-D multiaxial reinforcement, and damage tolerance. Despite these advantages, textile composites have not reached the level of implementation of laminated composites. In this paper, the opportunities provided by textile reinforced composites and the challenges that limit their implementation will be discussed in detail. Textile composites refer to a family of processes: weaving, braiding, knitting, and hybrids thereof. The various families of textiles will be defined and the basics of fabric formation for each family will be detailed. In particular, the strengths and weaknesses of each manufacturing technique will be addressed to provide a view of the applicability of each technology. This will include some guidance on shape formation capability, property ranges, size limitations, and estimates of cost to produce. Potential applications for these materials will be presented. Among the limitations on the application of textile reinforced composites is the lack of adequate modeling capabilities for these materials. Textile composites have rather large unit cell structures and are highly inhomogeneous throughout their volumes. These features provide benefits in manufacturing, but require novel modeling techniques to correctly understand the mechanical behavior. A review of analytical techniques applied to textile composites will be presented along with a discussion of the benefits and weaknesses of each of these methods. The enabling technologies needed to further the implementation of textile composites in structural applications will be discussed.

High uniformity of appearance is essential for textiles. Unintended variations of color between and within fabrics pose serious problems: their avoidance makes great demands on manufacturing and quality control at all stages from the extrusion of synthetic fibers and yarns up to the final finishing of a fabric. Most fabric inspection for quality control is visual. Unfortunately in some cases, the appearance of a color defect is a very poor guide to the true nature of the defect, a fact not generally recognized by the industry. This paper describes studies of the responses of observers to well . characterized model color defects using standard psychophysical methods. The results from this new approach will help the industry to understand these problems and provide a basis for the design of sensor systems to be used in automated fabric in spection.

Streakiness and barré have been problems for the textile industry for years. It is interesting that streakiness can be a problem in fabrics when it is barely detectable by instruments. This paper uses theory developed to explain the way humans see, to understand the origin of the fabric streakiness problem as a perception phenomenon. It then uses this understanding to suggest and evaluate options for improving, (i.e., reducing) the appearance of streakiness in real fabrics. Testing of the options suggested is done on simulated fabrics created under precisely controlled conditions on a high- quality color printer.

gaxis a recently described homeobox gene whose expression in the adult is largely confined to cardiovascular tissues. gaxhas been shown to be rapidly down-regulated in cultured vascular smooth muscle cells (VSMC) upon stimulation by serum or platelet-derived growth factor. The temporal profile of gaxexpression in vitromatches that of two families of growth arrest genes: the gasgenes and the gaddgenes. All of these genes are expressed at their highest levels in quiescent cells and are down-regulated following mitogen activation. Here we report that gaxis also down-regulated in vivoin the vascular wall in response to endothelial denudation by balloon angioplasty. The reduction in steady state levels of gaxmRNA is transient and occurs with a similar time course to that seen in vitro. The down-regulation of gaxin response to balloon injury mirrors the up-regulation seen in a number of early response genes such as c-mycand c-fos. This report is the first to document the in vivoexpression of a growth arrest gene which regulates proliferation of vascular smooth muscle cells. In addition, in contrast with previous reports which have demonstrated up-regulation of several genes following balloon injury and/or angioplasty, the present report demonstrates the down-regulationof a regulatory gene within hours of balloon injury. The characteristics of gaxsuggest it may be required to maintain the gene expression of proteins in VSMC that are associated with the nonproliferative or contractile phenotype in smooth muscle cells.

The geometry of a woven fabric is predicted accounting for process information. The processing information includes basic weave configurations as well as applied transverse compressive displacement during liquid moulding operations and yarn-yarn interaction within the fabric. The compaction and migration of individual yarns within the woven structure are modelled. To consider the usefulness of the developed model, the predicted geometries are used as input to a stiffness prediction model and the results are compared with experimental data on a range of woven composites - plain weave, orthogonally woven, and angle-interlock.

The geometry of a woven fabric is predicted accounting for process information. The processing information includes basic weave configurations as well as applied transverse compressive displacement during liquid moulding operations and yarn-yarn interaction within the fabric. The compaction and migration of individual yarns within the woven structure are modelled. To consider the usefulness of the developed model, the predicted geometries are used as input to a stiffness prediction model and the results are compared with experimental data on a range of woven composites - plain weave, orthogonally woven, and angle-interlock.

A methodology of the material-smart structural analysis proposed in this paper links micromechanical modelling of a complex fibrous reinforcement to a three-dimensional analysis of a structural part. The geometry of the reinforcing textile varies throughout the entire volume of a part, thus its stiffness characteristics are dependent on the spatial coordinates. The methodology addresses this by determining elastic properties of the textile composite in a local region (a ‘meso-volume’) through a processing science model. The ‘global’ structural analysis incorporates a variational formulation of the three-dimensional elasticity problem for an inhomogeneous anisotropic body, a division of the body into meso-volumes having individual elastic properties, further partition of each meso-volume into sub-elements, and application of special deficient spline functions for a local approximation of displacements with respect to all three coordinates. All the necessary external and internal boundary conditions can be satisfied with any prescribed accuracy in the proposed numerical procedure. Several numerical examples for woven and braided composite plates are considered to illustrate the applicability of the methodology and the calculational procedure.