Additive Manufactured Structures for the 12U Nanosatellite ERNST

One of the emerging technologies in recent years is additive manufacturing. It promises unprecedented design freedom in both modeling and rapid manufacturing. We are reaping the benefits of additive manufacturing for our 12U nanosatellite ERNST by printing the optical bench that supports the spacecraft payloads. We design the structures by using a finite-element numerical approach for optimizing the topology with respect to 1) available design space, 2) payload interfaces, 3) mechanical launch loads, and 4) thermal loads generated by the cryocooler of the MWIR main payload. We cope with the latter by integrating a pyramidal structured radiator surface in the optical bench as a functional element. Making use of the selective laser melting technique, we manufactured the first version of the optical bench for the engineering model of the ERNST spacecraft from AlSi10Mg alloy. Vibrational testing proved the suitability of our multidisciplinary design approach and the production quality. We are currently implementing the next version of the ERNST optical bench including spacecraft design changes and using Scalmalloy®, a material developed for additive manufacturing that provides high tensile strength and low thermal expansion. This marks a next step on the way to the application of additive manufactured components in space

Role of grain boundaries in tailoring electronic properties of polycrystalline graphene by chemical functionalization

Altres ajuts: Priority Program 1459 Graphene (German Research Foundation (DFG))Grain boundaries, inevitably present in chemical vapor deposited graphene, are expected to have considerable impact on the development of graphene-based hybrid materials with tailored material properties.Wedemonstrate here the critical role of polycrystallinity on the chemical functionalization of graphene comparing ozone-induced oxidation with remote plasma hydrogenation.Weshow that graphene oxidation and hydrogenation occur in two consecutive stages upon increasing defect density: an initial step in which surface-bound functional groups are generated, followed by the creation of vacancies. Remarkably, we find that hydrogenation yields homogeneously distributed defects while ozone-induced defects are preferentially accumulated at the grain boundaries eventually provoking local cracking of the structure. Supported by quantum simulations, our experimental findings reveal distinct electronic transport regimes depending on the density and distribution of induced defects on the polycrystalline graphene films. Our findings highlight the key role played by grain boundaries during graphene functionalization, and at the same time provide a novel perspective to tailor the properties of polycrystalline graphene

CD11c+ Cells Are Gatekeepers for Lymphocyte Trafficking to Infiltrated Islets During Type 1 Diabetes.

Type 1 diabetes (T1D) is a T cell mediated autoimmune disease that affects more than 19 million people with incidence increasing rapidly worldwide. For T cells to effectively drive T1D, they must first traffic to the islets and extravasate through the islet vasculature. Understanding the cues that lead to T cell entry into inflamed islets is important because diagnosed T1D patients already have established immune infiltration of their islets. Here we show that CD11

Constitutional Ethnography: An Introduction

Constitutional ethnography is the study of the central legal elements of polities using methods that are capable of recovering the lived detail of the politico-legal landscape. This article provides an introduction to this sort of study by contrasting constitutional ethnography with multivariate analysis and with nationalist constitutional analysis. The article advocates not a universal one-size-fits-all theory or an elegant model that abstracts away the distinctive, but instead outlines an approach that can identify a set of repertoires found in real cases. Learning the set of repertoires that constitutional ethnography reveals, one can see more deeply into particular cases. Constitutional ethnography has as its goal, then, not prediction but comprehension, not explained variation but thematization

A fNIRS investigation of speech planning and execution in adults who stutter

Our study aimed to determine the neural correlates of speech planning and execution in adults who stutter (AWS). Fifteen AWS and 15 controls (CON) completed two tasks that either manipulated speech planning or execution processing loads. Functional near-infrared spectroscopy (fNIRS) was used to measure changes in blood flow concentrations during each task, thus providing an indirect measure of neural activity. An image-based reconstruction technique was used to analyze the results and facilitate their interpretation in the context of previous functional neuroimaging studies of AWS that used positron emission tomography (PET) or functional magnetic resonance imaging (fMRI). For planning, we compared neural activity associated with high versus low planning load in AWS and CON. For execution, we compared the neural activity associated with overt versus covert naming in AWS and CON. Broadly, group level effects corroborate previous PET/fMRI findings including under-activation in lefthemisphere perisylvian speech-language networks and over-activation in righthemisphere homologues. Increased planning load revealed atypical left-hemisphere activation in AWS, whereas increased execution load yielded atypical right frontotemporo-parietal and bilateral motor activation in AWS. Our results add to the limited literature differentiating speech planning versus execution processes in AWS

CD11c+ Cells Are Gatekeepers for Lymphocyte Trafficking to Infiltrated Islets During Type 1 Diabetes

Type 1 diabetes (T1D) is a T cell mediated autoimmune disease that affects more than 19 million people with incidence increasing rapidly worldwide. For T cells to effectively drive T1D, they must first traffic to the islets and extravasate through the islet vasculature. Understanding the cues that lead to T cell entry into inflamed islets is important because diagnosed T1D patients already have established immune infiltration of their islets. Here we show that CD11c+ cells are a key mediator of T cell trafficking to infiltrated islets in non-obese diabetic (NOD) mice. Using intravital 2-photon islet imaging we show that T cell extravasation into the islets is an extended process, with T cells arresting in the islet vasculature in close proximity to perivascular CD11c+ cells. Antigen is not required for T cell trafficking to infiltrated islets, but T cell chemokine receptor signaling is necessary. Using RNAseq, we show that islet CD11c+ cells express over 20 different chemokines that bind chemokine receptors expressed on islet T cells. One highly expressed chemokine-receptor pair is CXCL16-CXCR6. However, NOD. CXCR6−/− mice progressed normally to T1D and CXCR6 deficient T cells trafficked normally to the islets. Even with CXCR3 and CXCR6 dual deficiency, T cells trafficked to infiltrated islets. These data reinforce that chemokine receptor signaling is highly redundant for T cell trafficking to inflamed islets. Importantly, depletion of CD11c+ cells strongly inhibited T cell trafficking to infiltrated islets of NOD mice. We suggest that targeted depletion of CD11c+ cells associated with the islet vasculature may yield a therapeutic target to inhibit T cell trafficking to inflamed islets to prevent progression of T1D

Donor Fecal Microbiota Transplantation Alters Gut Microbiota and Metabolites in Obese Individuals With Steatohepatitis

The intestinal microbiota has been linked to the development and prevalence of steatohepatitis in humans. Interestingly, steatohepatitis is significantly lower in individuals taking a plant-based, low-animal-protein diet, which is thought to be mediated by gut microbiota. However, data on causality between these observations in humans is scarce. In this regard, fecal microbiota transplantation (FMT) using healthy donors is safe and is capable of changing microbial composition in human disease. We therefore performed a double-blind randomized controlled proof-of-principle study in which individuals with hepatic steatosis on ultrasound were randomized to two study arms: lean vegan donor (allogenic n = 10) or own (autologous n = 11) FMT. Both were performed three times at 8-week intervals. A liver biopsy was performed at baseline and after 24 weeks in every subject to determine histopathology (Nonalcoholic Steatohepatitis Clinical Research Network) classification and changes in hepatic gene expression based on RNA sequencing. Secondary outcome parameters were changes in intestinal microbiota composition and fasting plasma metabolomics. We observed a trend toward improved necro-inflammatory histology, and found significant changes in expression of hepatic genes involved in inflammation and lipid metabolism following allogenic FMT. Intestinal microbial community structure changed following allogenic FMT, which was associated with changes in plasma metabolites as well as markers of .Conclusion:Allogenic FMT using lean vegan donors in individuals with hepatic steatosis shows an effect on intestinal microbiota composition, which is associated with beneficial changes in plasma metabolites and markers of steatohepatitis.Peer reviewe

A community resource for paired genomic and metabolomic data mining

Genomics and metabolomics are widely used to explore specialized metabolite diversity. The Paired Omics Data Platform is a community initiative to systematically document links between metabolome and (meta)genome data, aiding identification of natural product biosynthetic origins and metabolite structures.Peer reviewe

Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV