5,073 research outputs found
Aging-associated Alteration in the Cardiac MIF-AMPK Cascade in Response to Ischemic Stress
An important role for a macrophage migration inhibitory factor (MIF)-AMP-activated protein kinase (AMPK) signaling pathway in ameliorating myocardial damage following ischemia/reperfusion has been described. An aging-associated reduction in AMPK activity may be associated with a decline in the ability of cardiac cells to activate the MIF-AMPK cascade, thereby resulting in reduced tolerance to ischemic insults. To test this hypothesis, _in vivo_ regional ischemia was induced by occlusion of the left anterior descending (LAD) coronary artery in young (4-6 months) and aged (24-26 months) mice. The ischemic AMPK activation response was impaired in aged hearts compared to young ones (p<0.01). Notably, cardiac MIF expression in aged hearts was lower than in young hearts (p<0.01). Dual staining data clearly demonstrated larger infarct size in aged hearts following ischemia and reperfusion compared to young hearts (p<0.05). Ischemia-induced AMPK activation in MIF knock out (MIF KO) hearts was blunted, leading to greater contractile dysfunction of MIF KO cardiomyocytes during hypoxia than that of wild type (WT) cardiomyocytes. Finally exogenous recombinant MIF significantly reversed the contractile dysfunction of aged cardiomyocytes in response to hypoxia. We conclude that an aging-associated reduction in ischemic AMPK activation contributes to ischemic intolerance in aged hearts
Single and Two-Phase Heat Transfer Enhancement Using Longitudinal Vortex Generator in Narrow Rectangular Channel
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Regulation of reactive oxygen species during plant immunity through phosphorylation and ubiquitination of RBOHD.
Production of reactive oxygen species (ROS) is critical for successful activation of immune responses against pathogen infection. The plant NADPH oxidase RBOHD is a primary player in ROS production during innate immunity. However, how RBOHD is negatively regulated remains elusive. Here we show that RBOHD is regulated by C-terminal phosphorylation and ubiquitination. Genetic and biochemical analyses reveal that the PBL13 receptor-like cytoplasmic kinase phosphorylates RBOHD's C-terminus and two phosphorylated residues (S862 and T912) affect RBOHD activity and stability, respectively. Using protein array technology, we identified an E3 ubiquitin ligase PIRE (PBL13 interacting RING domain E3 ligase) that interacts with both PBL13 and RBOHD. Mimicking phosphorylation of RBOHD (T912D) results in enhanced ubiquitination and decreased protein abundance. PIRE and PBL13 mutants display higher RBOHD protein accumulation, increased ROS production, and are more resistant to bacterial infection. Thus, our study reveals an intricate post-translational network that negatively regulates the abundance of a conserved NADPH oxidase
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Phase Control on Surface for the Stabilization of High Energy Cathode Materials of Lithium Ion Batteries.
The development of high energy electrode materials for lithium ion batteries is challenged by their inherent instabilities, which become more aggravated as the energy densities continue to climb, accordingly causing increasing concerns on battery safety and reliability. Here, taking the high voltage cathode of LiNi0.5Mn1.5O4 as an example, we demonstrate a protocol to stabilize this cathode through a systematic phase modulating on its particle surface. We are able to transfer the spinel surface into a 30 nm shell composed of two functional phases including a rock-salt one and a layered one. The former is electrochemically inert for surface stabilization while the latter is designated to provide necessary electrochemical activity. The precise synthesis control enables us to tune the ratio of these two phases, and achieve an optimized balance between improved stability against structural degradation without sacrificing its capacity. This study highlights the critical importance of well-tailored surface phase property for the cathode stabilization of high energy lithium ion batteries
Fasciolopsis buski (Digenea: Fasciolidae) from China and India may represent distinct taxa based on mitochondrial and nuclear ribosomal DNA sequences
Sequences of primers used to amplify fragments of Fasciolopsis buski mitochondrial genome. (DOCX 17 kb
Improving Outfit Recommendation with Co-supervision of Fashion Generation
The task of fashion recommendation includes two main challenges: visual
understanding and visual matching. Visual understanding aims to extract
effective visual features. Visual matching aims to model a human notion of
compatibility to compute a match between fashion items. Most previous studies
rely on recommendation loss alone to guide visual understanding and matching.
Although the features captured by these methods describe basic characteristics
(e.g., color, texture, shape) of the input items, they are not directly related
to the visual signals of the output items (to be recommended). This is
problematic because the aesthetic characteristics (e.g., style, design), based
on which we can directly infer the output items, are lacking. Features are
learned under the recommendation loss alone, where the supervision signal is
simply whether the given two items are matched or not. To address this problem,
we propose a neural co-supervision learning framework, called the FAshion
Recommendation Machine (FARM). FARM improves visual understanding by
incorporating the supervision of generation loss, which we hypothesize to be
able to better encode aesthetic information. FARM enhances visual matching by
introducing a novel layer-to-layer matching mechanism to fuse aesthetic
information more effectively, and meanwhile avoiding paying too much attention
to the generation quality and ignoring the recommendation performance.
Extensive experiments on two publicly available datasets show that FARM
outperforms state-of-the-art models on outfit recommendation, in terms of AUC
and MRR. Detailed analyses of generated and recommended items demonstrate that
FARM can encode better features and generate high quality images as references
to improve recommendation performance
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