3,112 research outputs found
Analysis of partial-body and whole-body static sitting comfort
The whole-body comfort sensation was moderately to highly correlated with local body part comfort sensation in both sitting and driving, in order to understand what exact relationship exists between them, the seating comfort evaluations under the stimulus of four body parts (i.e. backs, waist, hips and thighs) were carried out for 15 subjects separately, subjective ratings on both partial-body and whole-body comfort are derived under different conditions. Impact factor (IF) of the partial-body comfort to whole-body comfort is calculated by the linear regression method, and the main variables are obtained by the stepwise regression algorithm. The most significant local body part in influencing whole body comfort is found at the region of hips, followed by backs, waist and hips. With impact factor analysis on partial body comfort, the results show that the local comfort feeling of waist is most potential to be influenced by other body parts, while the comfort sensitivity of thighs is the lowest
Sharp Multiple Instance Learning for DeepFake Video Detection
With the rapid development of facial manipulation techniques, face forgery
has received considerable attention in multimedia and computer vision community
due to security concerns. Existing methods are mostly designed for single-frame
detection trained with precise image-level labels or for video-level prediction
by only modeling the inter-frame inconsistency, leaving potential high risks
for DeepFake attackers. In this paper, we introduce a new problem of partial
face attack in DeepFake video, where only video-level labels are provided but
not all the faces in the fake videos are manipulated. We address this problem
by multiple instance learning framework, treating faces and input video as
instances and bag respectively. A sharp MIL (S-MIL) is proposed which builds
direct mapping from instance embeddings to bag prediction, rather than from
instance embeddings to instance prediction and then to bag prediction in
traditional MIL. Theoretical analysis proves that the gradient vanishing in
traditional MIL is relieved in S-MIL. To generate instances that can accurately
incorporate the partially manipulated faces, spatial-temporal encoded instance
is designed to fully model the intra-frame and inter-frame inconsistency, which
further helps to promote the detection performance. We also construct a new
dataset FFPMS for partially attacked DeepFake video detection, which can
benefit the evaluation of different methods at both frame and video levels.
Experiments on FFPMS and the widely used DFDC dataset verify that S-MIL is
superior to other counterparts for partially attacked DeepFake video detection.
In addition, S-MIL can also be adapted to traditional DeepFake image detection
tasks and achieve state-of-the-art performance on single-frame datasets.Comment: Accepted at ACM MM 2020. 11 pages, 8 figures, with appendi
Identification and characterization of microRNAs in Clonorchis sinensis of human health significance
<p>Abstract</p> <p>Background</p> <p><it>Clonorchis sinensis </it>is a zoonotic parasite causing clonorchiasis-associated human disease such as biliary calculi, cholecystitis, liver cirrhosis, and it is currently classified as carcinogenic to humans for cholangiocarcinoma. MicroRNAs (miRNAs) are non-coding, regulating small RNA molecules which are essential for the complex life cycles of parasites and are involved in parasitic infections. To identify and characterize miRNAs expressed in adult <it>C. sinensis </it>residing chronically in the biliary tract, we developed an integrative approach combining deep sequencing and bioinformatic predictions with stem-loop real-time PCR analysis.</p> <p>Results</p> <p>Here we report the use of this approach to identify and clone 6 new and 62,512 conserved <it>C. sinensis </it>miRNAs which belonged to 284 families. There was strong bias on families, family members and sequence nucleotides in <it>C. sinensis</it>. Uracil was the dominant nucleotide, particularly at positions 1, 14 and 22, which were located approximately at the beginning, middle and end of conserved miRNAs. There was no significant "seed region" at the first and ninth positions which were commonly found in human, animals and plants. Categorization of conserved miRNAs indicated that miRNAs of <it>C. sinensis </it>were still innovated and concentrated along three branches of the phylogenetic tree leading to bilaterians, insects and coelomates. There were two miRNA strategies in <it>C. sinensis </it>for its parasitic life: keeping a large category of miRNA families of different animals and keeping stringent conserved seed regions with high active innovation in other places of miRNAs mainly in the middle and the end, which were perfect for the parasite to perform its complex life style and for host changes.</p> <p>Conclusions</p> <p>The present study represented the first large scale characterization of <it>C. sinensis </it>miRNAs, which have implications for understanding the complex biology of this zoonotic parasite, as well as miRNA studies of other related species such as <it>Opisthorchis viverrini </it>and <it>Opisthorchis felineus </it>of human and animal health significance.</p
Seroprevalence of Toxoplasma gondii infection in pet dogs in Lanzhou, Northwest China
<p>Abstract</p> <p>Background</p> <p>In recent years, surveys of <it>Toxoplasma gondii </it>infection in dogs have been reported worldwide, including China. However, little is known about the prevalence of <it>T. gondii </it>in pet dogs in Northwest China. In the present study, the prevalence of <it>T. gondii </it>in pet dogs in Lanzhou, China was investigated using the modified agglutination test (MAT).</p> <p>Results</p> <p>In this survey, antibodies to <it>T. gondii </it>were found in 28 of 259 (10.81%) pet dogs, with MAT titers of 1:20 in 14 dogs, 1:40 in nine, 1:80 in four, and 1:160 or higher in one dog. The prevalence ranged from 6.67% to 16.67% among dogs of different ages, with low rates in young pet dogs, and high rates in older pet dogs. The seroprevalence in dogs >3 years old was higher than that in dogs ≤1 years old, but the difference was not statistically significant (<it>P ></it>0.05). The seroprevalence in male dogs was 12.50% (17 of 136), and in female dogs it was 8.94% (11 of 123), but the difference was not statistically significant (<it>P ></it>0.05).</p> <p>Conclusions</p> <p>A high prevalence of <it>T. gondii </it>infection was found in pet dogs in Lanzhou, Northwest China, which has implications for public health in this region. In order to reduce the risk of exposure to <it>T. gondii</it>, further measures and essential control strategies should be carried out rationally in this region.</p
Immunostimulatory efficacy and protective potential of putative TgERK7 protein in mice experimentally infected by Toxoplasma gondii
© 2020 The Author(s) The extracellular signal-regulated kinases (ERKs) serve as important determinants of cellular signal transduction pathways, and hence may play important roles during infections. Previous work suggested that putative ERK7 of Toxoplasma gondii is required for efficient intracellular replication of the parasite. However, the antigenic and immunostimulatory properties of TgERK7 protein remain unknown. The objective of this study was to produce a recombinant TgERK7 protein in vitro and to evaluate its effect on the induction of humoral and T cell-mediated immune responses against T. gondii infection in BALB/c mice. Immunization using TgERK7 mixed with Freund's adjuvants significantly increased the ratio of CD3e+CD4+ T/CD3e+CD8a+ T lymphocytes in spleen and elevated serum cytokines (IFN-γ, IL-2, IL-4, IL-10, IL-12p70, IL-23, MCP-1, and TNF-α) in immunized mice compared to control mice. On the contrary, immunization did not induce high levels of serum IgG antibodies. Five predicted peptides of TgERK7 were synthesized and conjugated with KLH and used to analyze the antibody specificity in the sera of immunized mice. We detected a progressive increase in the antibody level only against TgERK7 peptide A (DEVDKHVLRKYD). Antibody raised against this peptide significantly decreased intracellular proliferation of T. gondii in vitro, suggesting that peptide A can potentially induce a protective antibody response. We also showed that immunization improved the survival rate of mice challenged with a virulent strain and significantly reduced the parasite cyst burden within the brains of chronically infected mice. Our data show that TgERK7-based immunization induced TgERK7 peptide A-specific immune responses that can impart protective immunity against T. gondii infection. The therapeutic potential of targeting ERK7 signaling pathway for future toxoplasmosis treatment is warranted
Plasmoid ejection and secondary current sheet generation from magnetic reconnection in laser-plasma interaction
Reconnection of the self-generated magnetic fields in laser-plasma
interaction was first investigated experimentally by Nilson {\it et al.} [Phys.
Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a
solid target layer. An elongated current sheet (CS) was observed in the plasma
between the two laser spots. In order to more closely model magnetotail
reconnection, here two side-by-side thin target layers, instead of a single
one, are used. It is found that at one end of the elongated CS a fan-like
electron outflow region including three well-collimated electron jets appears.
The ( MeV) tail of the jet energy distribution exhibits a power-law
scaling. The enhanced electron acceleration is attributed to the intense
inductive electric field in the narrow electron dominated reconnection region,
as well as additional acceleration as they are trapped inside the rapidly
moving plasmoid formed in and ejected from the CS. The ejection also induces a
secondary CS
Changes in DNA methylation assessed by genomic bisulfite sequencing suggest a role for DNA methylation in cotton fruiting branch development
Cotton plant architecture, including fruit branch formation and flowering pattern, influences plant light exploitation, cotton yield and planting cost. DNA methylation has been widely observed at different developmental stages in both plants and animals and is associated with regulation of gene expression, chromatin remodelling, genome protection and other functions. Here, we investigated the global epigenetic reprogramming during the development of fruiting branches and floral buds at three developmental stages: the seedling stage, the pre-squaring stage and the squaring stage. We first identified 22 cotton genes which potentially encode DNA methyltransferases and demethylases. Among them, the homologous genes of CMT, DRM2 and MET1 were upregulated at pre-squaring and squaring stages, suggesting that DNA methylation is involved in the development of floral buds and fruit branches. Although the global methylation at all of three developmental stages was not changed, the CHG-type methylation of non-expressed genes was higher than those of expressed genes. In addition, we found that the expression of the homologous genes of the key circadian rhythm regulators, including CRY, LHY and CO, was associated with changes of DNA methylation at three developmental stages
Research progress on key technologies and equipment for quality preservation and fresh-keeping storage of high quality paddy
High quality paddy is rich in nutrition and good taste,but the storage period of high quality paddy is obviously lower than that of common paddy.Under conventional storage conditions,the safe storage period usually did not exceed 1.5 years.Aiming at the problems of yellowing,mildew,caking,quality and taste deterioration under conventional storage conditions,the storage quality characteristics of high quality paddy was studied to explore the effect of environment on yellowing high quality paddy.The detection method for yellowed paddy was established.Thenew control and treatment technology for condensation and caking were developed.Shelf life of high-quality paddy in different storage conditions was defined.The storage process for high-quality paddy in low temperature was integrated into demonstration
- …