3,568 research outputs found

    Mu-synthesis PID control of full-car with parallel active link suspension under variable payload

    Get PDF
    This paper presents a combined μ -synthesis PID control scheme, employing a frequency separation paradigm, for a recently proposed novel active suspension, the Parallel Active Link Suspension (PALS). The developed μ -synthesis control scheme is superior to the conventional H∞ control, previously designed for the PALS, in terms of ride comfort and road holding (higher frequency dynamics), with important realistic uncertainties, such as in vehicle payload, taken into account. The developed PID control method is applied to guarantee good chassis attitude control capabilities and minimization of pitch and roll motions (low frequency dynamics). A multi-objective control method, which merges the aforementioned PID and μ -synthesis-based controls is further introduced to achieve simultaneously the low frequency mitigation of attitude motions and the high frequency vibration suppression of the vehicle. A seven-degree-of-freedom Sport Utility Vehicle (SUV) full car model with PALS, is employed in this work to test the synthesized controller by nonlinear simulations with different ISO-defined road events and variable vehicle payload. The results demonstrate the control scheme's significant robustness and performance, as compared to the conventional passive suspension as well as the actively controlled PALS by conventional H∞ control, achieved for a wide range of vehicle payload considered in the investigation

    Dissociating stable nitrogen molecules under mild conditions by cyclic strain engineering

    Get PDF
    All quiet on the nitrogen front. The dissociation of stable diatomic nitrogen molecules (N-2) is one of the most challenging tasks in the scientific community and currently requires both high pressure and high temperature. Here, we demonstrate that N-2 can be dissociated under mild conditions by cyclic strain engineering. The method can be performed at a critical reaction pressure of less than 1 bar, and the temperature of the reaction container is only 40 degrees C. When graphite was used as a dissociated N* receptor, the normalized loading of N to C reached as high as 16.3 at/at %. Such efficient nitrogen dissociation is induced by the cyclic loading and unloading mechanical strain, which has the effect of altering the binding energy of N, facilitating adsorption in the strain-free stage and desorption in the compressive strain stage. Our finding may lead to opportunities for the direct synthesis of N-containing compounds from N-2

    Changes in targeted metabolomics in lung tissue of chronic obstructive pulmonary disease.

    Get PDF
    BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common chronic lung disease and its incidence is steadily increasing. COPD patients and mouse models of COPD share some similarities in lung pathology and physiology. We performed this study to explore the potential metabolic pathways involved in the pathogenesis of COPD and to discover the COPD-associated biomarkers. Furthermore, we aimed to examine how much the mouse model of COPD was similar and different to human COPD in terms of the altered metabolites and pathways. METHODS: Twenty human lung tissue samples (ten COPD and ten controls) and twelve mice lung tissue samples (six COPD and six controls) were analyzed by targeted HM350 metabolomics, and multivariate and pathway analysis were performed by Kyoto Encyclopedia of Genes and Genomes (KEGG) database. RESULTS: The counts of many metabolites such as amino acids, carbohydrates and carnitines were changed in both COPD patients and mice compared to controls, respectively. While lipid metabolism was changed only in COPD mice. After KEGG analysis, we found these altered metabolites involved in COPD through aging, apoptosis, oxidative stress and inflammation pathways. CONCLUSIONS: The expressions of metabolites changed in both COPD patients and cigarette smoke exposed (CS-exposed) mice. And there were also some differences between COPD patients and mouse models due to the differences between species. Our study suggested the dysregulation in amino acid metabolism, energy production pathway and perhaps lipid metabolism may be significantly related to the pathogenesis of COPD

    Foreword

    Get PDF
    The postsynaptic density protein-95/disks large/zonula occludens-1 (PDZ) protein domain family is one of the most common proteinprotein interaction modules in mammalian cells, with paralogs present in several hundred human proteins. PDZ domains are found in most cell types, but neuronal proteins, for example, are particularly rich in these domains. The general function of PDZ domains is to bring proteins together within the appropriate cellular compartment, thereby facilitating scaffolding, signaling, and trafficking events. The many functions of PDZ domains under normal physiological as well as pathological conditions have been reviewed recently. In this review, we focus on the molecular details of how PDZ domains bind their protein ligands and their potential as drug targets in this context

    Molecular characterisation of protist parasites in human-habituated mountain gorillas (Gorilla beringei beringei), humans and livestock, from Bwindi impenetrable National Park, Uganda

    Get PDF
    Over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. Zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (Gorilla beringei beringei) of Uganda. Here, we assess the occurrence of Cryptosporidium, Cyclospora, Giardia, and Entamoeba infecting mountain gorillas in the Bwindi Impenetrable National Park (BINP), Uganda, using molecular methods. We also assess the occurrence of these parasites in humans and livestock species living in overlapping/adjacent geographical regions

    Rhomboid family member 2 regulates cytoskeletal stress-associated Keratin 16.

    Get PDF
    Keratin 16 (K16) is a cytoskeletal scaffolding protein highly expressed at pressure-bearing sites of the mammalian footpad. It can be induced in hyperproliferative states such as wound healing, inflammation and cancer. Here we show that the inactive rhomboid protease RHBDF2 (iRHOM2) regulates thickening of the footpad epidermis through its interaction with K16. K16 expression is absent in the thinned footpads of irhom2-/- mice compared with irhom2+/+mice, due to reduced keratinocyte proliferation. Gain-of-function mutations in iRHOM2 underlie Tylosis with oesophageal cancer (TOC), characterized by palmoplantar thickening, upregulate K16 with robust downregulation of its type II keratin binding partner, K6. By orchestrating the remodelling and turnover of K16, and uncoupling it from K6, iRHOM2 regulates the epithelial response to physical stress. These findings contribute to our understanding of the molecular mechanisms underlying hyperproliferation of the palmoplantar epidermis in both physiological and disease states, and how this 'stress' keratin is regulated

    4d N=2 Gauge Theories and Quivers: the Non-Simply Laced Case

    Get PDF
    We construct the BPS quivers with superpotential for the 4d N=2 gauge theories with non-simply laced Lie groups (B_n, C_n, F_4 and G_2). The construction is inspired by the BIKMSV geometric engineering of these gauge groups as non-split singular elliptic fibrations. From the categorical viewpoint of arXiv:1203.6743, the fibration of the light category L(g) over the (degenerate) Gaiotto curve has a monodromy given by the action of the outer automorphism of the corresponding unfolded Lie algebra. In view of the Katz--Vafa `matter from geometry' mechanism, the monodromic idea may be extended to the construction of (Q, W) for SYM coupled to higher matter representations. This is done through a construction we call specialization.Comment: 42 pages, 2 figure

    Soft normed rings

    Get PDF
    corecore