982 research outputs found

    PipeNet: Selective Modal Pipeline of Fusion Network for Multi-Modal Face Anti-Spoofing

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    Face anti-spoofing has become an increasingly important and critical security feature for authentication systems, due to rampant and easily launchable presentation attacks. Addressing the shortage of multi-modal face dataset, CASIA recently released the largest up-to-date CASIA-SURF Cross-ethnicity Face Anti-spoofing(CeFA) dataset, covering 3 ethnicities, 3 modalities, 1607 subjects, and 2D plus 3D attack types in four protocols, and focusing on the challenge of improving the generalization capability of face anti-spoofing in cross-ethnicity and multi-modal continuous data. In this paper, we propose a novel pipeline-based multi-stream CNN architecture called PipeNet for multi-modal face anti-spoofing. Unlike previous works, Selective Modal Pipeline (SMP) is designed to enable a customized pipeline for each data modality to take full advantage of multi-modal data. Limited Frame Vote (LFV) is designed to ensure stable and accurate prediction for video classification. The proposed method wins the third place in the final ranking of Chalearn Multi-modal Cross-ethnicity Face Anti-spoofing Recognition Challenge@CVPR2020. Our final submission achieves the Average Classification Error Rate (ACER) of 2.21 with Standard Deviation of 1.26 on the test set.Comment: Accepted to appear in CVPR2020 WM

    Intra-Storm Temporal Patterns of Rainfall in China Using Huff Curves

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    Intra-storm temporal distributions of precipitation are important for infiltration, runoff, and erosion process understanding and models. A convenient and established method for characterizing precipitation hyetographs is the use of non-dimensional Huff curves. In this study, 11,801 erosive rainfall events with 1 min resolution data collected over 30 to 40 years from 18 weather stations located across the central and eastern parts of China were analyzed to produce Huff curves. Each event was classified according to the quartile period within the event that contained the greatest fraction of rainfall. The results showed that 38.3% of events had the maximum rainfall amounts in the first quartile, followed by the second (26.8%), third (22.4%), and fourth (12.5%) quartiles. Quartile I and II events were generally characteristic of shorter duration and heavier intensity events. Quartile I events averaged 23% shorter durations than quartile IV events, whereas the mean intensity (Iavg), mean maximum 30 min intensity (I30), and mean rainfall erosivity index (EI30) were 1.71, 1.22, and 1.23 times greater, respectively, than those for quartile IV and were significant at a 5% level based on two-sample t-tests. The proportion of quartile I events was less for events of longer duration, whereas the proportions of quartile III and IV events were greater. Two-sample Kolmogorov-Smirnov tests suggested that regional Huff curves can be derived for the central and eastern parts of China. Regional Huff curves developed in this study exhibited dissimilarities in terms of the percentages of storms for different quartiles and the shapes of the curves compared to those reported for Illinois, peninsular Malaysia, and Santa Catarina in Brazil

    Sulfadiazine Sodium Ameliorates the Metabolomic Perturbation in Mice Infected with Toxoplasma gondii

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    In this study, we analyzed the global metabolomic changes associated with Toxoplasma gondii infection in mice in the presence or absence of sulfadiazine sodium (SDZ) treatment. BALB/c mice were infected with T. gondii GT1 strain and treated orally with SDZ (250 g/ml in water) for 12 consecutive days. Mice showed typical manifestations of illness at 20 days postinfection (dpi); by 30 dpi, 20% had survived and developed latent infection. We used ultraperformance liquid chromatography-mass spectrometry to profile the serum metabolomes in control (untreated and uninfected) mice, acutely infected mice, and SDZ-treated and infected mice. Infection induced significant perturbations in the metabolism of-linolenic acid, purine, pyrimidine, arginine, tryptophan, valine, glycerophospholipids, and fatty acyls. However, treatment with SDZ seemed to alleviate the serum metabolic alterations caused by infection. The restoration of the serum metabolite levels in the treated mice was associated with better clinical outcomes. These data indicate that untargeted metabolomics can reveal biochemical pathways associated with restoration of the metabolic status of T. gondii-infected mice following SDZ treatment and could be used to monitor responses to SDZ treatment. This study provides a new systems approach to elucidate the metabolic and therapeutic effects of SDZ in the context of murine toxoplasmosis. K E Y W O R D S Toxoplasma gondii, biomarkers, metabolomics, mice, serum metabolites, sulfadiazine sodium Toxoplasma gondii, an obligate intracellular protozoan parasite, is highly prevalent in warm-blooded animals and humans (1). T. gondii comprises three clonal lineages (type I, type II, and type III) (2). Despite 98% genetic similarity, dramatic differences in virulence exist among strains belonging to these T. gondii genotypes (3). Humans acquire infection mainly by ingesting undercooked meat containing tissue cysts or oocysts from contaminated water (4). Acute infection with this parasite is mediated by the aggressive, fast-replicating, tachyzoite stage, which can cause encephalitis or retinochoroiditis. In addition, reactivation of the latent form (i.e., bradyzoites-containing cysts) of T. gondii can cause life-threatening conditions and even death in immuno-compromised individuals (5)

    Assessing the effectiveness of complex dietary candidate probiotics on growth performance, digestive enzyme activity, antioxidant capability, and intestinal microbiota of koi carp (Cyprinus carpio var. koi)

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    The present study aimed to evaluate the effectiveness of three complex dietary candidate probiotics (LDJ, LAC, and LJD) composing different candidate probiotic combinations on the growth performance, digestive enzyme activities, antioxidant parameters, and intestinal microbiota in koi carp (Cyprinus carpio var. koi). After a 60-days feeding trial, samples from the control and three candidate probiotic groups were obtained and analyzed. The results suggested that all complex dietary candidate probiotic treatments (LDJ, LAC, and LJD) improved the growth performance, nutrition utilization, and intestinal digestive enzyme activities compared with the control group. Furthermore, a dietary supplement with LAC or LJD is more efficient in growth and digestive enzyme than LDJ. The antioxidant enzyme activities, including SOD (superoxide dismutase), CAT (catalase), and GPX (glutathione peroxidase), were intensively improved, the GSH (glutathione) contents increased, and the MDA (malondialdehyde) contents decreased to different extents depending on the tissues and kinds of candidate probiotics. Dietary candidate probiotics also regulated the intestinal microbiota composition: LDJ and LAC increased the proportion of potential candidate probiotics and reduced the level of pollutants reducing bacteria and geosmin producer Nannocystis. The LJD group had a similar pattern of the dominant bacteria to the control sample, suggesting a minor disturbance of the gut microbiota of koi carp. Overall, the multi-strain complex candidate probiotics LAC and LJD are more efficient in growth performance and digestive enzymes

    The complete mitochondrial genomes for three Toxocara species of human and animal health significance

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    <p>Abstract</p> <p>Background</p> <p>Studying mitochondrial (mt) genomics has important implications for various fundamental areas, including mt biochemistry, physiology and molecular biology. In addition, mt genome sequences have provided useful markers for investigating population genetic structures, systematics and phylogenetics of organisms. <it>Toxocara canis, Toxocara cati </it>and <it>Toxocara malaysiensis </it>cause significant health problems in animals and humans. Although they are of importance in human and animal health, no information on the mt genomes for any of <it>Toxocara </it>species is available.</p> <p>Results</p> <p>The sizes of the entire mt genome are 14,322 bp for <it>T. canis</it>, 14029 bp for <it>T. cati </it>and 14266 bp for <it>T. malaysiensis</it>, respectively. These circular genomes are amongst the largest reported to date for all secernentean nematodes. Their relatively large sizes relate mainly to an increased length in the AT-rich region. The mt genomes of the three <it>Toxocara </it>species all encode 12 proteins, two ribosomal RNAs and 22 transfer RNA genes, but lack the ATP synthetase subunit 8 gene, which is consistent with all other species of Nematode studied to date, with the exception of <it>Trichinella spiralis</it>. All genes are transcribed in the same direction and have a nucleotide composition high in A and T, but low in G and C. The contents of A+T of the complete genomes are 68.57% for <it>T. canis</it>, 69.95% for <it>T. cati </it>and 68.86% for <it>T. malaysiensis</it>, among which the A+T for <it>T. canis </it>is the lowest among all nematodes studied to date. The AT bias had a significant effect on both the codon usage pattern and amino acid composition of proteins. The mt genome structures for three <it>Toxocara </it>species, including genes and non-coding regions, are in the same order as for <it>Ascaris suum </it>and <it>Anisakis simplex</it>, but differ from <it>Ancylostoma duodenale</it>, <it>Necator americanus </it>and <it>Caenorhabditis elegans </it>only in the location of the AT-rich region, whereas there are substantial differences when compared with <it>Onchocerca volvulus</it>,<it>Dirofiliria immitis </it>and <it>Strongyloides stercoralis</it>. Phylogenetic analyses based on concatenated amino acid sequences of 12 protein-coding genes revealed that the newly described species <it>T. malaysiensis </it>was more closely related to <it>T. cati </it>than to <it>T. canis</it>, consistent with results of a previous study using sequences of nuclear internal transcribed spacers as genetic markers.</p> <p>Conclusion</p> <p>The present study determined the complete mt genome sequences for three roundworms of human and animal health significance, which provides mtDNA evidence for the validity of <it>T. malaysiensis </it>and also provides a foundation for studying the systematics, population genetics and ecology of these and other nematodes of socio-economic importance.</p

    Cationic Porphyrins with Large Side Arm Substituents as Resonance Light Scattering Ratiometric Probes for Specific Recognition of Nucleic Acid G-quadruplexes

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    Specific G-quadruplex-probing is crucial for both biological sciences and biosensing applications. Most reported probes are focused on fluorescent or colorimetric recognition of G-quadruplexes. Herein, for the first time, we reported a new specific G-quadruplex-probing technique—resonance light scattering (RLS)-based ratiometric recognition. To achieve the RLS probing of G-quadruplexes in the important physiological pH range of 7.4-6.0, four water soluble cationic porphyrin derivatives, including an unreported octa-cationic porphyrin, with large side arm substituents were synthesized and developed as RLS probes. These RLS probes were demonstrated to work well for ratiometric recognition of G-quadruplexes with high specificity against single- and double-stranded DNAs, including long double-stranded ones. The working mechanism was speculated to be based on the RLS signal changes caused by porphyrin protonation that was promoted by the end-stacking of porphyrins on Gquadruplexes. This work adds an important member in G-quadruplex probe family, thus providing a useful tool for studies on G-quadruplex-related events concerning G-quadruplex formation, destruction and changes in size, shape and aggregation. As a proofof-concept example of applications, the RLS probes were demonstrated to work well for label-free and sequence-specific sensing of microRNA. This work also provides a simple and useful way for the preparation of cationic porphyrins with high charges

    TKwinFormer: Top k Window Attention in Vision Transformers for Feature Matching

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    Local feature matching remains a challenging task, primarily due to difficulties in matching sparse keypoints and low-texture regions. The key to solving this problem lies in effectively and accurately integrating global and local information. To achieve this goal, we introduce an innovative local feature matching method called TKwinFormer. Our approach employs a multi-stage matching strategy to optimize the efficiency of information interaction. Furthermore, we propose a novel attention mechanism called Top K Window Attention, which facilitates global information interaction through window tokens prior to patch-level matching, resulting in improved matching accuracy. Additionally, we design an attention block to enhance attention between channels. Experimental results demonstrate that TKwinFormer outperforms state-of-the-art methods on various benchmarks. Code is available at: https://github.com/LiaoYun0x0/TKwinFormer.Comment: 11 pages, 7 figure
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