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O3 was applied as an efficient oxidant in the pre-oxidation of cellulose under the mild conditions for oxidation-hydrolysis of cellulose without additional catalyst. After treated by O3 at 120 °C for 4 h, some hydroxymethyl groups on cellulose structure were oxidized to carboxyl groups which act as the active sites for the hydrolysis under the hydrothermal conditions to break the glycoside bonds of cellulose. Much lower oxidation temperature and short treatment time make this method more competitive than the conventional oxidation-hydrolysis strategy (210 °C, 48 h) where O2 was used as the oxidant. Furthermore, in this oxidation-hydrolysis strategy, efficient hydrolysis of cellulose to glucose can be realized with a high cellulose/water mass ratio (40 wt%). Correspondingly, a glucose aqueous solution with high concentration (50.9 g L−1) can be obtained. High concentration of glucose is favorable for the further application in fermentation or chemical conversion. This work provides a new, mild, and green oxidation strategy for oxidation-hydrolysis of cellulose without additional catalyst. [ABSTRACT FROM AUTHOR]

Given a directed graph G, the directed densest subgraph (DDS) problem refers to finding a subgraph from G, whose density is the highest among all subgraphs of G. The DDS problem is fundamental to a wide range of applications, such as fake follower detection and community mining. Theoretically, the DDS problem closely connects to other essential graph problems, such as network flow and bipartite matching. However, existing DDS solutions suffer from efficiency and scalability issues. In this paper, we develop a convex-programming-based solution by transforming the DDS problem into a set of linear programs. Based on the duality of linear programs, we develop efficient exact and approximation algorithms. Particularly, our approximation algorithm can support flexible parameterized approximation guarantees. We further investigate using GPU to speed up the solution of convex programs in parallel and achieve hundreds of times speedup compared to the original Frank–Wolfe computation. We have performed an extensive empirical evaluation of our approaches on eight real large datasets. The results show that our proposed algorithms are up to five orders of magnitude faster than the state of the art. [ABSTRACT FROM AUTHOR]

A novel Fe–Mn binary oxide (FMBO)/bone char composite (FMBC) was synthesized and utilized to simultaneously adsorb Sb(III) and Cd(II) from aqueous phase in this study. The successful loading of Fe–Mn binary oxide on the bone char surface was revealed by the results of scanning electron microscope, X-ray diffraction patterns, and energy dispersive spectroscopy of FMBC. The FMBC exhibited remarkable ability of simultaneous removing Sb(III) and Cd(II) from aqueous, and the presence of Cd(II) enhanced Langmuir theoretical maximum adsorption capacity for Sb(III) significantly from 67.8 to 209.0 mg/g. Besides, FMBC could efficiently remove Sb(III) and Cd(II) in the wide initial pH range of 2–7. The influences of ionic strength, co-existing anions, humic acid, and temperature on the adsorption of Sb(III) and Cd(II), and the application potential of FMBC in actual groundwater were investigated. The main mechanisms of Sb(III) and Cd(II) adsorption onto FMBC involved redox, electrostatic interaction, surface complexation, ion exchange, and precipitation. The result of X-ray photoelectron spectroscopy and mapping spectrum analysis revealed that Mn(III) on FMBC played the key role in the Sb(III) oxidation, while FeOOH worked as the adsorption sites of FMBC. Meanwhile, the hydroxyapatite on FMBC also contributed to the removal of Cd(II). The presence of Cd(II) not only increased the positive charge on the surface of FMBC but also formed the Fe–Sb–Cd ternary complex, promoting the removal of Sb. This work provides valuable information for the application of FMBO/bone char as a cost-effective adsorbent to remediate co-pollution of Sb(III) and Cd(II) in aqueous environment. [ABSTRACT FROM AUTHOR]

Corncob is one of the main by-products of agricultural biomass in corn-producing area. Here, the valorization of corncob polysaccharide components to produce furfural and glucose was studied. Firstly, corncob was treated by high-pressure CO2-H2O; the in situ formed-carbonic acid catalyzed the selective hydrolysis of hemicellulose component with xylo-oligosaccharide and xylan as the main products. The obtained liquid fraction was further upgraded to furfural with H2SO4 as catalyst. After reaction at 140 °C for 1 h, 7.0 g L−1 of furfural was given. The conversion of C5 sugar and the selectivity of furfural was 56% and 72%, respectively. Then, the cellulose component of the residual solid fraction was depolymerized by oxidation-hydrolysis method. The hydroxymethyl group on the cellulose unit was partially oxidized to carboxyl group, which catalyzed the following hydrolysis of the cellulose component to glucose. 17.2 g of glucose per 100 g oxidized solid fraction was given at 170 °C for 6 h with water as the solvent. Additionally, the oxidation-hydrolysis strategy was also performed for the hydrolysis of the industrial furfural residues. [ABSTRACT FROM AUTHOR]

Objectives: This study retrospectively investigated in which cycle measurable residual disease (MRD) is associated with prognosis in patients in first complete remission (CR1) of intermediate-risk acute myeloid leukemia (AML). Methods: The study enrolled 235 younger patients with intermediate-risk AML. MRD was evaluated by multiparameter flow cytometry after the 1st, 2nd, and 3rd chemotherapy cycles (MRD1–3, respectively). Results: No significant association was detected after the 1st and 2nd cycles. However, the 5-year incidence of relapse was higher in the MRD3-positive group (n = 99) than in the negative group (n = 136) (48.7% vs. 13.7%, P = 0.005), while 5-year disease-free survival (DFS) and overall survival (OS) were lower in the MRD3-positive group than in the negative group (43.2% vs. 81.0% and 45.4% vs. 84.1%; P = 0.003 and 0.005, respectively). Allogeneic hematopoietic stem cell transplantation led to a lower 5-year relapse, and higher DFS and OS rates than chemotherapy in the MRD3-positive group (22.3% vs. 71.5%, 65.9% vs. 23.0%, and 67.1% vs. 23.9%; P < 0.001, 0.002, and 0.022, respectively), but did not affect the MRD-negative group. Conclusions: MRD3 could serve as an indicator for post-remission treatment choice and help improve outcomes for intermediate-risk AML in CR1. [ABSTRACT FROM AUTHOR]

Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes, and its neural mechanisms underlying the pathogenesis remain unclear. Autophagy plays an important role in neurodegenerative diseases and nerve tissue injury. Lipin1 is a phosphatidic acid phosphatase enzyme that converts phosphatidic acid (PA) into diacylglycerol (DAG), a precursor of triacylglycerol and phospholipids which plays an important role in maintaining normal peripheral nerve conduction function. However, whether Lipin1 involved in the pathogenesis of DPN via regulation of autophagy is not elucidated. Here, we show that the Lipin1 expression was downregulated in streptozotocin (STZ)-induced DPN rat model. Interestingly, STZ prevented DAG synthesis, and resulted in autophagic hyperactivity, effects which may increase the apoptosis of Schwann cells and lead to demyelination in sciatic nerve in DPN rats. More importantly, upregulation of lipin1 in the DPN rats ameliorated autophagy disorders and pathological changes of the sciatic nerve, which associated with the increase of the motor nerve conductive velocity (MNCV) in DPN rats. In contrast, knockdown of lipin1 exacerbates neuronal abnormalities and facilitates the genesis of DPN phenotypes in rats. In addition, overexpression of lipin1 in RSC96 cells also significantly decreased the autophagic hyperactivity and apoptosis induced by hyperglycemia. These results suggest that lipin1 may exert neuroprotection within the sciatic nerve anomalies and may serve as a potential therapeutic target for the treatment of DPN. [ABSTRACT FROM AUTHOR]

The metalloprotease lethal factor (LF) from Bacillus anthracis plays a vital role in anthrax toxin action, and thus becomes a target for anti-anthrax therapy. Following the guidelines based on existing metalloprotease inhibitors, we designed a 'first-generation' LF inhibitor R9LF-1. This inhibitor was shown to be very stable by itself in a wide range of pH and temperature and able to inhibit LF activity in vitro. However, as we reported previously in the presence of LF, this inhibitor was degraded to a small molecular weight species, resulting in a significantly decreased ability to protect MAPKK from cleavage by LF as well as to protect murine macrophages from lethal toxin. In order to elucidate this unusual phenomenon to build solid basis for high-efficiency LF inhibitor development, we performed extensive research to study the effect of LF on its peptide-based inhibitor. Effects of temperature and incubation period of time on generation of the smaller peptide (short version R9LF-1) by LF as well as its catalytic domain were analyzed. We found that LF degraded R9LF-1 with maximum efficiency in the pH range of 7.0-8.5, which correlates well with the range of LF enzymatic activity with its native substrate. The degradation showed a deviation from normal hyperbolic kinetics but a similarity to the kinetics profile of an enzyme-catalyzed reaction with positive cooperativity. The short version R9LF-1 had decreased inhibitory activity toward LF; surprisingly, BIAcore results suggested a better affinity for its binding to LF. In addition, R9LF-1 was not hydrolyzed by other common proteases, such as chymotrypsin and pepsin, suggesting hydrolysis of the bond between amino acid and hydroxamate groups is unique to LF. This study calls for caution when designing peptide-based LF inhibitors and when interpreting effects of these types of inhibitors. [ABSTRACT FROM AUTHOR]

Na/K-ATPases are membrane-associated enzymes responsible for the active transport of Na and K ions across cell membranes, generating chemical and electrical gradients. These enzymes' α-subunit provides catalytic function, binding and hydrolyzing ATP, and itself becoming phosphorylated during the transport cycle. In this study, Na/K-ATPase α-subunit cDNA was cloned from gill tissue of the swimming crab Portunus trituberculatus by reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end methods. Analysis of the nucleotide sequence revealed that the cDNA had a full-length of 3 833 base pairs (bp), with an open reading frame of 3 120 bp, 5′ untranslated region (UTR) of 317 bp, and 3′ UTR of 396 bp. The sequence encoded a 1 039 amino acid protein with a predicted molecular weight of 115.57 kDa and with estimated pI of 5.21. It was predicted here to possess all expected features of Na/K-ATPase members, including eight transmembrane domains, putative ATP-binding site, and phosphorylation site. Comparison of amino acid sequences showed that the P. trituberculatus α-subunit possessed an overall identity of 75%-99% to that of other organisms. Phylogenetic analysis revealed that this α-subunit was in the same category as those of crustaceans. Quantitative real-time RT-PCR analysis indicated that this α-subunit's transcript were most highly expressed in gill and lowest in muscle. RT-PCR analysis also revealed that α-subunit expression in crab gill decreased after 2 and 6 h, but increased after 12, 24, 48, and 72 h. In addition, α-subunit expression in hepatopancreas of crab decreased after 2-72 h. These facts indicated that the crab's Na/K-ATPase α-subunit was potentially involved in the observed acute response to low salinity stress. [ABSTRACT FROM AUTHOR]

Advanced glycation end products (AGEs)-induced vasculopathy, including oxidative stress, inflammation and apoptosis responses, contributes to the high morbidity and mortality of coronary artery diseases in diabetic patients. The present study was conducted to evaluate the protective activity of liquiritin (Liq) on AGEs-induced endothelial dysfunction and explore its underlying mechanisms. After pretreatment with Liq, a significant reduction in AGEs-induced apoptosis, as well as reactive oxygen species generation and malondialdehyde level in human umbilical vein endothelial cells (HUVECs) were observed via acridine orange/ethidium bromide fluorescence staining test. Notably, Liq also significantly increased AGEs-reduced superoxide dismutase activity. Furthermore, the pretreatment with receptor for advanced glycation end products (RAGE)-antibody or Liq remarkably down-regulated TGF-beta1 and RAGE protein expressions and significantly blocked NF-κB activation which were proved by immunocytochemistry or immunofluorescence assays. These results indicated that Liq held potential for the protection on AGEs-induced endothelial dysfunction via RAGE/NF-κB pathway in HUVECs and might be a promising agent for the treatment of vasculopathy in diabetic patients. [ABSTRACT FROM AUTHOR]

Runyang Bridge is a newly built cable-supported bridge that crosses the Yangtze River in China. The bridge is composed of one suspension bridge and one cable-stayed bridge. During the construction of the bridge, a structural health monitoring system (SHMS) was installed, which was designed by the Southeast University. Since the bridge was open to traffic, quantities of structural ambient responses have been recorded by the SHMS. And, it’s really important to extract structrural information from these records for health monitoring. This paper presents the study on modal identification of the bridge. The dynamic properites including modal frequencies, mode shapes and damping ratios are extracted from the ambient responses. Two identification methods are employed including the enhanced frequency domain decomposition and the stochastic subspace identification. The identified modal parameters from the two methods are compared. Results show that modal frequencies and mode shapes from the two methods are almost the same while the damping ratios are different. [ABSTRACT FROM AUTHOR]