166 research outputs found
Glucose Enhances Leptin Signaling through Modulation of AMPK Activity
Leptin exerts its action by binding to and activating the long form of leptin receptors (LEPRb). LEPRb activates JAK2 that subsequently phosphorylates and activates STAT3. The JAK2/STAT3 pathway is required for leptin control of energy balance and body weight. Defects in leptin signaling lead to leptin resistance, a primary risk factor for obesity. Body weight is also regulated by nutrients, including glucose. Defects in glucose sensing also contribute to obesity. Here we report crosstalk between leptin and glucose. Glucose starvation blocked the ability of leptin to stimulate tyrosyl phosphorylation and activation of JAK2 and STAT3 in a variety of cell types. Glucose dose-dependently enhanced leptin signaling. In contrast, glucose did not enhance growth hormone-stimulated phosphorylation of JAK2 and STAT5. Glucose starvation or 2-deoxyglucose-induced inhibition of glycolysis activated AMPK and inhibited leptin signaling; pharmacological inhibition of AMPK restored the ability of leptin to stimulate STAT3 phosphorylation. Conversely, pharmacological activation of AMPK was sufficient to inhibit leptin signaling and to block the ability of glucose to enhance leptin signaling. These results suggest that glucose and/or its metabolites play a permissive role in leptin signaling, and that glucose enhances leptin sensitivity at least in part by attenuating the ability of AMPK to inhibit leptin signaling
Rapid Determination of Saponins in the Honey-Fried Processing of Rhizoma Cimicifugae by Near Infrared Diffuse Reflectance Spectroscopy.
ObjectiveA model of Near Infrared Diffuse Reflectance Spectroscopy (NIR-DRS) was established for the first time to determine the content of Shengmaxinside I in the honey-fried processing of Rhizoma Cimicifugae.MethodsShengmaxinside I content was determined by high-performance liquid chromatography (HPLC), and the data of the honey-fried processing of Rhizoma Cimicifugae samples from different batches of different origins by NIR-DRS were collected by TQ Analyst 8.0. Partial Least Squares (PLS) analysis was used to establish a near-infrared quantitative model.ResultsThe determination coefficient R² was 0.9878. The Cross-Validation Root Mean Square Error (RMSECV) was 0.0193%, validating the model with a validation set. The Root Mean Square Error of Prediction (RMSEP) was 0.1064%. The ratio of the standard deviation for the validation samples to the standard error of prediction (RPD) was 5.5130.ConclusionThis method is convenient and efficient, and the experimentally established model has good prediction ability, and can be used for the rapid determination of Shengmaxinside I content in the honey-fried processing of Rhizoma Cimicifugae
Pricing Decision of Closed-Loop Supply Chain to Improve Service Level under Patent Protection
This paper constructs a two-level closed-loop supply chain system consisting of original parts manufacturers and parts distributors. Based on the different preferences of consumers for remanufactured parts and new parts, four combination models of patent protection and service improvement are constructed. Through comparative analysis, the impact of implementing patent protection policies by original parts manufacturers and improving service levels by parts distributors on the pricing decisions of the closed-loop supply chain is explored.Through the comparison between related models and the verification of calculation examples, it is found that (1) a manufacturer prevents the price of new products from being affected by the price of remanufactured products and upgrading of service level by introducing royalties, which reduces its loss of profit; (2) in the absence of patent protection, the manufacturerꞌs profit decreases as the level of service increases; in the presence of patent protection, the manufacturerꞌs profit increases as the level of service increases; (3) retailersꞌ profits decrease after the manufacturer introduces royalties, which discourages them to improve service levels for remanufactured products; (4) as retailers raise the service level of the remanufactured products, the profits of the manufacturer and third-party manufacturers keep increasing, while the profits of the retailers first increase and then decrease
EMVLight: a Multi-agent Reinforcement Learning Framework for an Emergency Vehicle Decentralized Routing and Traffic Signal Control System
Emergency vehicles (EMVs) play a crucial role in responding to time-critical
calls such as medical emergencies and fire outbreaks in urban areas. Existing
methods for EMV dispatch typically optimize routes based on historical
traffic-flow data and design traffic signal pre-emption accordingly; however,
we still lack a systematic methodology to address the coupling between EMV
routing and traffic signal control. In this paper, we propose EMVLight, a
decentralized reinforcement learning (RL) framework for joint dynamic EMV
routing and traffic signal pre-emption. We adopt the multi-agent advantage
actor-critic method with policy sharing and spatial discounted factor. This
framework addresses the coupling between EMV navigation and traffic signal
control via an innovative design of multi-class RL agents and a novel
pressure-based reward function. The proposed methodology enables EMVLight to
learn network-level cooperative traffic signal phasing strategies that not only
reduce EMV travel time but also shortens the travel time of non-EMVs.
Simulation-based experiments indicate that EMVLight enables up to a
reduction in EMV travel time as well as an shorter average travel time
compared with existing approaches.Comment: 19 figures, 10 tables. Manuscript extended on previous work
arXiv:2109.05429, arXiv:2111.0027
Mouse hepatocyte overexpression of NF‐κB‐inducing kinase (NIK) triggers fatal macrophage‐dependent liver injury and fibrosis
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109646/1/hep27348-sup-0001-suppinfo01.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/109646/2/hep27348.pd
The molecular clouds in a section of the third Galactic quadrant: observational properties and chemical abundance ratio between CO and its isotopologues
We compare the observational properties between CO, CO, and
CO and summarize the observational parameters based on 7069 clouds
sample from the Milky Way Imaging Scroll Painting (MWISP) CO survey in a
section of the third Galactic quadrant. We find that the CO angular area
() generally increases with that of CO (), and the ratio of to is 0.38 by
linear fitting. We find that the CO and CO flux are tightly
correlated as with both fluxes
calculated within the CO-bright region. This indicates that the
abundance is a constant to be 6.5 for all samples under assumption of local thermodynamic equilibrium
(LTE). Additionally, we observed that the X-factor is approximately constant in
large sample molecular clouds. Similarly, we find with both fluxes calculated within
CO-bright region, which indicates that the abundance ratios stays the same value 9.7 across the
molecular clouds under LTE assumption. The linear relationships of vs. and vs.
hold not only for the CO-bright region or CO-bright region, but
also for the entire molecular cloud scale with lower flux ratio. The abundance
ratio inside clouds shows a strong
correlation with column density and temperature. This indicates that the
is dominated by a combination of chemical
fractionation, selectively dissociation, and self-shielding effect inside
clouds.Comment: 11 pages, 16 figures, 1 table, accepted by A
Anomalous Floquet non-Hermitian skin effect in a ring resonator lattice
We present a one-dimensional coupled ring resonator lattice exhibiting a
variant of the non- Hermitian skin effect (NHSE) that we call the anomalous
Floquet NHSE. Unlike existing approaches to achieving the NHSE by engineering
gain and loss on different ring segments, our design uses fixed on-site gain or
loss in each ring. The anomalous Floquet NHSE is marked by the existence of
skin modes at every value of the Floquet quasienergy, allowing for broadband
asymmetric transmission. Varying the gain/loss induces a non-Hermitian
topological phase transition, reversing the localization direction of the skin
modes. An experimental implementation in an acoustic lattice yields good
agreement with theoretical predictions, with a very broad relative bandwidth of
around 40%.Comment: 7 pages, 3 figure
Mine yOur owN Anatomy: Revisiting Medical Image Segmentation with Extremely Limited Labels
Recent studies on contrastive learning have achieved remarkable performance
solely by leveraging few labels in the context of medical image segmentation.
Existing methods mainly focus on instance discrimination and invariant mapping.
However, they face three common pitfalls: (1) tailness: medical image data
usually follows an implicit long-tail class distribution. Blindly leveraging
all pixels in training hence can lead to the data imbalance issues, and cause
deteriorated performance; (2) consistency: it remains unclear whether a
segmentation model has learned meaningful and yet consistent anatomical
features due to the intra-class variations between different anatomical
features; and (3) diversity: the intra-slice correlations within the entire
dataset have received significantly less attention. This motivates us to seek a
principled approach for strategically making use of the dataset itself to
discover similar yet distinct samples from different anatomical views. In this
paper, we introduce a novel semi-supervised 2D medical image segmentation
framework termed Mine yOur owN Anatomy (MONA), and make three contributions.
First, prior work argues that every pixel equally matters to the model
training; we observe empirically that this alone is unlikely to define
meaningful anatomical features, mainly due to lacking the supervision signal.
We show two simple solutions towards learning invariances - through the use of
stronger data augmentations and nearest neighbors. Second, we construct a set
of objectives that encourage the model to be capable of decomposing medical
images into a collection of anatomical features in an unsupervised manner.
Lastly, our extensive results on three benchmark datasets with different
labeled settings validate the effectiveness of our proposed MONA which achieves
new state-of-the-art under different labeled settings
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