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To screen, prepare, identify, and evaluate the activities of natural antioxidants for treating chronic diseases caused by oxidative stress. Two algal proteins, namely ZD10 and ZD60, precipitated with 10 and 60% (NH4)2SO4 were extracted from red algae Eucheuma cottonii (E. cottonii) and hydrolyzed using five proteolytic enzymes. The results showed that ZD60 played the most significant role in the enhancement of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH⋅) scavenging activity (25.91 ± 0.24%) among all protein hydrolysates. Subsequently, six antioxidant peptides (EP1-EP6) were isolated from the papain hydrolysate of ZD60 by ultrafiltration and chromatography methods. Their amino acid sequences were identified as Thr-Ala (EP1), Met-Asn (EP2), Tyr-Ser-Lys-Thr (EP3), Tyr-Ala-Val-Thr (EP4), Tyr-Leu-Leu (EP5), and Phe-Tyr-Lys-Ala (EP6) with molecular weights of 190.21, 263.33, 497.55, 452.51, 407.51, and 527.62 Da, respectively. Of which, EP3, EP4, EP5, and EP6 showed strong scavenging activities on DPPH⋅, hydroxyl radical (HO⋅), and superoxide anion radical (O- 2⋅). Moreover, EP4 and EP5 could significantly protect human umbilical vein endothelial cells (HUVECs) from H2O2-induced oxidative damage by increasing the levels of antioxidant enzyme systems including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) to reduce the levels of reactive oxygen species (ROS) (60.51 and 51.74% of model group) and malondialdehyde (MDA) (75.36 and 64.45% of model group). In addition, EP4 and EP5 could effectively inhibit H2O2-induced apoptosis by preventing HUVECs from early apoptosis to late apoptosis. These results indicated that the antioxidant peptides derived from E. cottonii, especially EP4 and EP5, could serve as the natural antioxidants applied in pharmaceutical products to treat chronic cardiovascular diseases caused by oxidative damage, such as coronary heart disease, atherosclerosis, etc.

Abstract Humans have the ability to perceive kinetic depth effects, i.e., to perceived 3D shapes from 2D projections of rotating 3D objects. This process is based on a variety of visual cues such as lighting and shading effects. However, when such cues are weak or missing, perception can become faulty, as demonstrated by the famous silhouette illusion example of the spinning dancer. Inspired by this, we establish objective and subjective evaluation models of rotated 3D objects by taking their projected 2D images as input. We investigate five different cues: ambient luminance, shading, rotation speed, perspective, and color difference between the objects and background. In the objective evaluation model, we first apply 3D reconstruction algorithms to obtain an objective reconstruction quality metric, and then use quadratic stepwise regression analysis to determine weights of depth cues to represent the reconstruction quality. In the subjective evaluation model, we use a comprehensive user study to reveal correlations with reaction time and accuracy, rotation speed, and perspective. The two evaluation models are generally consistent, and potentially of benefit to inter-disciplinary research into visual perception and 3D reconstruction.

Abstract Researchers have achieved great success in dealing with 2D images using deep learning. In recent years, 3D computer vision and geometry deep learning have gained ever more attention. Many advanced techniques for 3D shapes have been proposed for different applications. Unlike 2D images, which can be uniformly represented by a regular grid of pixels, 3D shapes have various representations, such as depth images, multi-view images, voxels, point clouds, meshes, implicit surfaces, etc. The performance achieved in different applications largely depends on the representation used, and there is no unique representation that works well for all applications. Therefore, in this survey, we review recent developments in deep learning for 3D geometry from a representation perspective, summarizing the advantages and disadvantages of different representations for different applications. We also present existing datasets in these representations and further discuss future research directions.

With the development of the Internet, malware has become one of the most significant threats. Recognizing specific types of malware is an important step toward effective removal. Malware visualization is an important branch of malware static analysis techniques, where a piece of malware is turned into an image for visualization and classification. Despite great success, it is still difficult to extract effective texture feature representations for challenging datasets. The existing methods use global image features which are sensitive to relative code locations. In this paper, we present a new learning framework to obtain more discriminative and robust feature descriptors. The proposed method works with the existing local descriptors such as local binary patterns and dense scale-invariant feature transform, by grouping them into blocks and by using a new bag-of-visual-words model to obtain robust features, which are more flexible than global features and more robust than local features. We evaluate the proposed method on three malware databases. The experimental results demonstrate that the obtained descriptors lead to the state-of-the-art classification performance.

This paper presents a new image synthesis method for image style transfer. For some common methods, the textures and colors in the style image are sometimes applied inappropriately to the content image, which generates artifacts. In order to improve the results, we propose a novel method based on a new strategy that combines both local and global style losses. On the one hand, a style loss function based on a local approach is used to keep the style details. On the other hand, another style loss function based on global measures is used to capture more global structural information. The results on various images show that the proposed method reduces artifacts while faithfully transferring the style image's characteristics and preserving the structure and color of the content image.

Eight novel and three known antioxidant peptides isolated from protein hydrolysate of Moringa oleifera seeds, using ultrafiltration, anion-exchange chromatography, gel filtration chromatography and reversed phase high performance liquid chromatography (RP-HPLC). The novel peptides were identified as Gly-Tyr (GY), Pro-Phe-Glu (PFE), Tyr-Thr-Arg (YTR), Phe-Gly (FG), Gln-Tyr (QY), Ile-Asn (IN), Ser-Phe (SF), Ser-Pro (SP), and the known peptides were identified as Tyr-Phe-Glu (YFE), Ile-Tyr (IY) and Leu-Tyr (LY), respectively, using protein amino acid sequence analyzer and electrospray ionization-mass spectrometry. All the eleven peptides exhibited strong scavenging activities on 2,2-Diphenyl-1picrylhydrazyl radical (DPPH·) (EC50 2.28, 1.60, 1.77, 2.15, 0.97, 1.30, 0.75, 0.91, 1.21, 0.79, and 1.37 mg/L, respectively) and 2,2-azino-bis (3-ethylbenzothia zoline-6-sulfonic acid) diammonium salt radical (ABTS·+) (EC50 1.03, 0.84, 0.95, 0.65, 0.37, 0.54, 0.33, 0.36, 0.67, 0.32 and 0.38 mg/mL, respectively). In addition, SF and QY showed protective effects on oxidative damage Chang liver cells induced by H2O2, and the contents of aspartate aminotransferase (ALT), alanine aminotransferase (AST) and malondialdehyde (MDA) decreased with the increasing concentrations of SF and QY. Furthermore, SF and QY could significantly increase the levels of superoxide dismutase (SOD) and catalase (CAT), thereby effectively scavenge reactive oxygen species (ROS) in H2O2-induced oxidative damaged Chang liver cells (P

Alcalase was screened out for hydrolyzing the swim bladder proteins of miiuy croaker (Miichthys miiuy) from five proteases using hydroxyl radical scavenging assay, and its optimal hydrolysis conditions were be determined as time 3.5 h, temperature 55 °C, pH 9.5, solid-liquid ratio 1:5, and enzyme dose 2.5%. Ten new antioxidant peptides were isolated from SMAH using ultrafiltration and consecutive chromatography, and their sequences were identified as FYKWP, FTGMD, GFEPY, YLPYA, FPPYERRQ, GFYAA, FSGLR, FPYLRH, VPDDD, and GIEWA. FPYLRH and GIEWA exhibited strong scavenging activities on hydroxyl radical (EC50 0.68 mg/mL and 0.71 mg/mL for FPYLRH and GIEWA, respectively), DPPH radical (EC50 0.51 mg/mL and 0.78 mg/mL for FPYLRH and GIEWA, respectively), and superoxide anion radical (EC50 0.34 mg/mL and 0.30 mg/mL for FPYLRH and GIEWA, respectively). In addition, FPYLRH and GIEWA could be effectively against lipid peroxidation in the β-carotene linoleic acid and in the linoleic acid emulsion system.

Abstract We consider the problem of learning a representation of both spatial relations and dependencies between objects for indoor scene design. We propose a novel knowledge graph framework based on the entity-relation model for representation of facts in indoor scene design, and further develop a weaklysupervised algorithm for extracting the knowledge graph representation from a small dataset using both structure and parameter learning. The proposed framework is flexible, transferable, and readable. We present a variety of computer-aided indoor scene design applications using this representation, to show the usefulness and robustness of the proposed framework.

Doxorubicin (DOX) is a commonly used anthracycline in treatments of leukemia, lymphoma and breast cancer in humans and has been limited by its cardiotoxicity, which is manifested congestive heart failure in the worst condition. The present study showed that the marine carotenoid of fucoxanthin could exert cardioprotective effect against the DOX-induced injury in ICR mice. And then, the protective effects and mechanisms of fucoxanthin on DOX-induced injury of neonatal rat cardiomyocytes were investigated. The results demonstrated that fucoxanthin significantly reduced mice toxic death triggered by DOX. The protective effects were also showed by the suppression of apoptotic cell death in cardiomyocytes. Further study revealed that fucoxanthin-produced suppression of MAPK activated by DOX was involved in the cardioprotection. The findings confirmed the cardioprotective effect of fucoxanthin against DOX-induced cardiotoxicity by protecting myocardial cells from lipid peroxidation and apoptosis, which would likely result in an increased therapeutic window of DOX in cancer therapy.

Abstract Malaria, caused by protozoan parasites of the genus Plasmodium especially by the most prevalent parasite Plasmodium falciparum , represents one of the most devastating and common infectious disease globally. Nearly half of the world population is under the risk of being infected, and more than 200 million new clinical cases with around half a million deaths occur annually. Drug therapy is the mainstay of antimalarial therapy, yet current drugs are threatened by the development of resistance, so it's imperative to develop new antimalarials with great potency against both drug-susceptible and drug-resistant malaria. Triazoles, bearing a five-membered heterocyclic ring with three nitrogen atoms, exhibit promising in vitro antiplasmodial and in vivo antimalarial activities. Moreover, several triazole-based drugs have already used in clinics for the treatment of various diseases, demonstrating the excellent pharmaceutical profiles. Therefore, triazole derivatives have the potential for clinical deployment in the control and eradication of malaria. This review covers the recent advances of triazole derivatives especially triazole hybrids as potential antimalarials. The structure-activity relationship is also discussed to provide an insight for rational designs of more efficient antimalarial candidates. Graphical abstract Triazoles represents a fruitful matrix for the development of various new drugs, and some derivatives exhibited promising in vitro antiplasmodial and in vivo antimalarial activities. This review covers the recent advances on triazole derivatives as potential antimalarials. The structure-activity relationship is also discussed for further rational designs of more active triazole derivatives. Image 1 Highlights • Triazole derivatives possess promising in vitro antiplasmodial and in vivo antimalarial properties. • This review covers the recent advances of new triazole derivatives as potential antimalarials. • The structure-activity relationship is also discussed. [ABSTRACT FROM AUTHOR]

Abstract Quinoline and quinolone motifs which act as structural subunits of more complex natural products are ubiquitous in nature, and they are useful pharmacophores which play a pivotal role in drug development. Compared with the corresponding monomeric compounds, the dimers usually exhibited some unique properties, so dimers have caused great interests in recent years. Quinline and quinolone dimers possess various biological properties such as antibacterial, anticancer, antimalarial and antitubercular activities, and some of them which are exemplified by piperaquine have already used in clinical practice. Numerous quinline and quinolone dimers have been synthesized and screened for their in vitro and in vivo biological activities, and some of them exhibited promising potency. Therefore, quinline and quinolone dimers have the potential for clinical deployment in the control and eradication of various diseases. This review covers the recent advances of quinline and quinolone dimers as bioactive substances. The structure-activity relationship was also discussed to provide an insight for rational designs of more active quinline and quinolone dimers. Graphical abstract Quinoline and quinolone dimers exhibit various biological and pharmacological properties, and some currently used drugs bearing quinoline and quinolone dimers. This review covers the recent advances on quinline and quinolone dimers as potential antibacterial, anticancer, antimalarial and antitubercular agents. The structure-activity relationship is also discussed to provide an insight for further rational designs of more active quinline and quinolone dimers. Image 1 Highlights • Quinolines and quinolones occupy an important position in the development of new drugs. • Quinoline and quinolone dimers possess diverse pharmacological properties. • Some quinoline and quinolone dimers have already used in clinical practice. • The structure-activity relationship is also discussed. [ABSTRACT FROM AUTHOR]

Tropical mountain river systems that drain rainforests and experience tropical monsoons typically demonstrate high runoff and discharge a disproportionate amount of particulate load to the world''s oceans compared with other more temperate river systems. As a typical tropical small mountainous river with an broad continental shelf system and wave dominated environment, the Kelantan River is one of the few north-flowing streams in Southeast Asia that discharges into the broad and shallow continental shelf of South China Sea. The existence of seasonal variations of salinity, turbidity, and sediment composition indicate that coarse-grained sediments are deposited rapidly when terrestrial sediments delivered by the Kelantan River leave the river mouth. They are then reworked by wave action during the rainy season, leading to the development and rapid migration of barrier spits near the west side of the river mouth. Under the influence of the seasonal variations in the river plume, fine-grained sediments discharged into the sea by the Kelantan River are transported both along-shore and cross-shore, and most of them are deposited in the continental shelf area within 10 km of the river mouth, because of rapid removal of sediments from the river plume. The spatial distribution patterns of sediment composition, C/N ratio, terrestrial organic carbon content, and Sr/Al ratio also support our conclusion. • Terrestrial materials are mainly buried near the estuary in small tropical mountainous river-shallow broad shelf system. • Wave action determines the coarse sediment transport that result in development and migration of sand spits. • River plume is the main controlling factor in fine-grain particle cross-shore and along-shore transport. [ABSTRACT FROM AUTHOR]

Three new aaptamines ( 1-3 ) together with two known derivatives ( 4-5 ) were isolated from the South China Sea sponge Aaptos suberitoides . The structures of all compounds were unambiguously elucidated by spectroscopic analyses as well as the comparison with literature data. All the compounds were evaluated for their cytotoxic activities against five human cancer cell lines including H1299, H520, SCG7901, CNE-2 and SW680 cells. As a result, compounds 3-5 showed moderate cytotoxicities against H1299 and H520 cells with IC 50 values ranging from 12.9 to 20.6 μg/mL. Besides, compounds 3-5 also showed potent inhibitory activities toward cyclin-dependent kinase-2 (CDK2) with IC 50 values of 14.3, 3.0 and 6.0 μg/mL, respectively. In addition, compounds 3-5 significantly induced G1 arrests of H1299 cells at low concentrations. Drug affinity responsive target stability (DARTS) experiments were carried out and further demonstrated that compound 3 could effectively bind with CDK2 protein and protect it from the degradation by pronase.

To screen, prepare, identify, and evaluate the activities of natural antioxidants for treating chronic diseases caused by oxidative stress. Two algal proteins, namely ZD10 and ZD60, precipitated with 10 and 60% (NH 4 ) 2 SO 4 were extracted from red algae Eucheuma cottonii ( E. cottonii ) and hydrolyzed using five proteolytic enzymes. The results showed that ZD60 played the most significant role in the enhancement of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH⋅) scavenging activity (25.91 ± 0.24%) among all protein hydrolysates. Subsequently, six antioxidant peptides (EP1-EP6) were isolated from the papain hydrolysate of ZD60 by ultrafiltration and chromatography methods. Their amino acid sequences were identified as Thr-Ala (EP1), Met-Asn (EP2), Tyr-Ser-Lys-Thr (EP3), Tyr-Ala-Val-Thr (EP4), Tyr-Leu-Leu (EP5), and Phe-Tyr-Lys-Ala (EP6) with molecular weights of 190.21, 263.33, 497.55, 452.51, 407.51, and 527.62 Da, respectively. Of which, EP3, EP4, EP5, and EP6 showed strong scavenging activities on DPPH⋅, hydroxyl radical (HO⋅), and superoxide anion radical (O- 2⋅). Moreover, EP4 and EP5 could significantly protect human umbilical vein endothelial cells (HUVECs) from H 2 O 2 -induced oxidative damage by increasing the levels of antioxidant enzyme systems including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) to reduce the levels of reactive oxygen species (ROS) (60.51 and 51.74% of model group) and malondialdehyde (MDA) (75.36 and 64.45% of model group). In addition, EP4 and EP5 could effectively inhibit H 2 O 2 -induced apoptosis by preventing HUVECs from early apoptosis to late apoptosis. These results indicated that the antioxidant peptides derived from E. cottonii , especially EP4 and EP5, could serve as the natural antioxidants applied in pharmaceutical products to treat chronic cardiovascular diseases caused by oxidative damage, such as coronary heart disease, atherosclerosis, etc., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sun, Gao, Wang, Li, Wang and Wang.)

We develop a framework to virtually unroll fragile historical parchment scrolls, which cannot be physically unfolded via a sequence of X-ray tomographic slices, thus providing easy access to those parchments whose contents have remained hidden for centuries. The first step is to produce a topologically correct segmentation, which is challenging as the parchment layers vary significantly in thickness, contain substantial interior textures and can often stick together in places. For this purpose, our method starts with linking the broken layers in a slice using the topological structure propagated from its previous processed slice. To ensure topological correctness, we identify fused regions by detecting junction sections, and then match them using global optimization efficiently solved by the blossom algorithm, taking into account the shape energy of curves separating fused layers. The fused layers are then separated using as-parallel-as-possible curves connecting junction section pairs. To flatten the segmented parchment, pixels in different frames need to be put into alignment. This is achieved via a dynamic programming-based global optimization, which minimizes the total matching distances and penalizes stretches. Eventually, the text of the parchment is revealed by ink projection. We demonstrate the effectiveness of our approach using challenging real-world data sets, including the water damaged fifteenth century Bressingham scroll.

Benefiting from global rank constraints, the low-rank representation (LRR) method has been shown to be an effective solution to subspace learning. However, the global mechanism also means that the LRR model is not suitable for handling large-scale data or dynamic data. For large-scale data, the LRR method suffers from high time complexity, and for dynamic data, it has to recompute a complex rank minimization for the entire data set whenever new samples are dynamically added, making it prohibitively expensive. Existing attempts to online LRR either take a stochastic approach or build the representation purely based on a small sample set and treat new input as out-of-sample data. The former often requires multiple runs for good performance and thus takes longer time to run, and the latter formulates online LRR as an out-of-sample classification problem and is less robust to noise. In this paper, a novel online LRR subspace learning method is proposed for both large-scale and dynamic data. The proposed algorithm is composed of two stages: static learning and dynamic updating. In the first stage, the subspace structure is learned from a small number of data samples. In the second stage, the intrinsic principal components of the entire data set are computed incrementally by utilizing the learned subspace structure, and the LRR matrix can also be incrementally solved by an efficient online singular value decomposition algorithm. The time complexity is reduced dramatically for large-scale data, and repeated computation is avoided for dynamic problems. We further perform theoretical analysis comparing the proposed online algorithm with the batch LRR method. Finally, experimental results on typical tasks of subspace recovery and subspace clustering show that the proposed algorithm performs comparably or better than batch methods, including the batch LRR, and significantly outperforms state-of-the-art online methods.