Fast Hierarchical Deep Unfolding Network for Image Compressed Sensing

By integrating certain optimization solvers with deep neural network, deep unfolding network (DUN) has attracted much attention in recent years for image compressed sensing (CS). However, there still exist several issues in existing DUNs: 1) For each iteration, a simple stacked convolutional network is usually adopted, which apparently limits the expressiveness of these models. 2) Once the training is completed, most hyperparameters of existing DUNs are fixed for any input content, which significantly weakens their adaptability. In this paper, by unfolding the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA), a novel fast hierarchical DUN, dubbed FHDUN, is proposed for image compressed sensing, in which a well-designed hierarchical unfolding architecture is developed to cooperatively explore richer contextual prior information in multi-scale spaces. To further enhance the adaptability, series of hyperparametric generation networks are developed in our framework to dynamically produce the corresponding optimal hyperparameters according to the input content. Furthermore, due to the accelerated policy in FISTA, the newly embedded acceleration module makes the proposed FHDUN save more than 50% of the iterative loops against recent DUNs. Extensive CS experiments manifest that the proposed FHDUN outperforms existing state-of-the-art CS methods, while maintaining fewer iterations.Comment: Accepted by ACM MM 202

Indolic Uremic Solutes Enhance Procoagulant Activity of Red Blood Cells through Phosphatidylserine Exposure and Microparticle Release

Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs), the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS) and indole-3-acetic acid (IAA) on procoagulant activity (PCA) of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients). Phosphatidylserine (PS) exposure of RBCs and their microparticles (MPs) release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca2+ ([Ca2+]) with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca2+]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process

Emissions and characteristics of particulate matter from rainforest burning in the Southeast Asia

The burning of tropical rainforests in the Southeast Asia emits considerable particulate matter (PM), which has significant effects on air quality and human health. Lacking of reliable local EFPM for rainforest burning in the Southeast Asia is one of the most important causes for uncertainty of the estimated pollutant emissions. In this study, 23 types of rainforest plants, including herbaceous, shrubs, evergreen trees and deciduous trees were burned to determine emission factors of PM and multiple chemical species, including organic carbon (OC), elemental carbon (EC), water soluble ions (WSIs), and elements using a custom-made dilution system. EFPM for the four vegetation types was relatively higher for burning of deciduous trees, followed by evergreen trees, shrubs and herbaceous. EFPM in the Southeast Asia was higher than those in the North America, South America and Africa, with biomass type and ambient temperature and humidity as the determinant factors. Organic matter was the dominant constituent of PM, accounting for 57%, followed by EC, WSIs and elements. Source profile of WSIs varied larger than those of OC, EC and elements for different biomass type and areas. For example, the fraction of K+, a typical biomass burning tracer, to WSIs was 30% and 28% in the Southeast Asia and North America, respectively, which was almost 2 times lower than those in the Europe. Finally, the temporal and spatial scales of PM, OC, and EC emissions from rainforest burning in the Southeast Asia in 2016 were estimated, based on the updated measured EFs. The annual emissions (minimum-maximum) were 1527-2834 Gg, 529.9-1100 Gg, and 81.02-150.4 Gg for PM, OC and EC, respectively. Our results suggest that using of EFPM reported in other regions would lead to an underestimation of PM emissions in the Southeast Asia

A new sensitive LC/MS/MS analysis of vitamin D metabolites using a click derivatization reagent, 2-nitrosopyridine

There is an increased demand for comprehensive analysis of vitamin D metabolites. This is a major challenge, especially for 1α,25-dihydroxyvitamin D [1α,25(OH)2VitD], because it is biologically active at picomolar concentrations. 4-Phenyl-1,2,4-triazoline-3,5-dione (PTAD) was a revolutionary reagent in dramatically increasing sensitivity of all diene metabolites and allowing the routine analysis of the bioactive, but minor, vitamin D metabolites. A second generation of reagents used large fixed charge groups that increased sensitivity at the cost of a deterioration in chromatographic separation of the vitamin D derivatives. This precludes a survey of numerous vitamin D metabolites without redesigning the chromatographic system used. 2-Nitrosopyridine (PyrNO) demonstrates that one can improve ionization and gain higher sensitivity over PTAD. The resulting vitamin D derivatives facilitate high-resolution chromatographic separation of the major metabolites. Additionally, a liquid-liquid extraction followed by solid-phase extraction (LLE-SPE) was developed to selectively extract 1α,25(OH)2VitD, while reducing 2- to 4-fold ion suppression compared with SPE alone. LLE-SPE followed by PyrNO derivatization and LC/MS/MS analysis is a promising new method for quantifying vitamin D metabolites in a smaller sample volume (100 µL of serum) than previously reported methods. The PyrNO derivatization method is based on the Diels-Alder reaction and thus is generally applicable to a variety diene analytes