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1.
IEEE Trans Image Process ; 25(12): 5905-5919, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27740484

RESUMO

We address the problem of face video retrieval in TV-series, which searches video clips based on the presence of specific character, given one face track of his/her. This is tremendously challenging because on one hand, faces in TV-series are captured in largely uncontrolled conditions with complex appearance variations, and on the other hand, retrieval task typically needs efficient representation with low time and space complexity. To handle this problem, we propose a compact and discriminative representation for the huge body of video data, named compact video code (CVC). Our method first models the face track by its sample (i.e., frame) covariance matrix to capture the video data variations in a statistical manner. To incorporate discriminative information and obtain more compact video signature suitable for retrieval, the high-dimensional covariance representation is further encoded as a much lower dimensional binary vector, which finally yields the proposed CVC. Specifically, each bit of the code, i.e., each dimension of the binary vector, is produced via supervised learning in a max margin framework, which aims to make a balance between the discriminability and stability of the code. Besides, we further extend the descriptive granularity of covariance matrix from traditional pixel-level to more general patch-level, and proceed to propose a novel hierarchical video representation named spatial pyramid covariance along with a fast calculation method. Face retrieval experiments on two challenging TV-series video databases, i.e., the Big Bang Theory and Prison Break, demonstrate the competitiveness of the proposed CVC over the state-of-the-art retrieval methods. In addition, as a general video matching algorithm, CVC is also evaluated in traditional video face recognition task on a standard Internet database, i.e., YouTube Celebrities, showing its quite promising performance by using an extremely compact code with only 128 bits.

2.
IEEE Trans Image Process ; 25(12): 5920-5932, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28113507

RESUMO

Facial expression is a temporally dynamic event which can be decomposed into a set of muscle motions occurring in different facial regions over various time intervals. For dynamic expression recognition, two key issues, temporal alignment and semantics-aware dynamic representation, must be taken into account. In this paper, we attempt to solve both problems via manifold modeling of videos based on a novel mid-level representation, i.e., expressionlet. Specifically, our method contains three key stages: 1) each expression video clip is characterized as a spatial-temporal manifold (STM) formed by dense low-level features; 2) a universal manifold model (UMM) is learned over all low-level features and represented as a set of local modes to statistically unify all the STMs; and 3) the local modes on each STM can be instantiated by fitting to the UMM, and the corresponding expressionlet is constructed by modeling the variations in each local mode. With the above strategy, expression videos are naturally aligned both spatially and temporally. To enhance the discriminative power, the expressionlet-based STM representation is further processed with discriminant embedding. Our method is evaluated on four public expression databases, CK+, MMI, Oulu-CASIA, and FERA. In all cases, our method outperforms the known state of the art by a large margin.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-449486

RESUMO

OBJECTIVE: To evaluate the role of total glucosides of peony (TGP) as adjuvant therapy for prevention of cardiac allograft rejection in rats. METHODS: Rats with cardiac allograft were randomly divided into control group, tacrolimus-treated group, TGP-treated group and tacrolimus plus TGP-treated group. Graft survival time was observed. Allografts in some cases were examined by histological study seven days after transplantation. At the same time, the levels of CD4(+) and CD8(+) T cell subsets in peripheral blood were examined by using flow cytometry; the hepatic function and renal function of recipients were also tested. RESULTS: The graft survival time of the tacrolimus-treated group and tacrolimus plus TGP-treated group was (11.14+/-1.57) d and (13.57+/-1.99) d, respectively. The graft survival time of the tacrolimus plus TGP-treated group was longer than that of the tacrolimus-treated group (P<0.05). The histological study showed that the rejection of the tacrolimus plus TGP-treated group was slighter than that of the tacrolimus-treated group. The levels of CD4(+) T cell subset in the peripheral blood of the tacrolimus-treated and tacrolimus plus TGP-treated groups were (38.71+/-5.15)% and (32.43+/-4.39)% respectively 7 days after transplantation. The level of CD4(+) T cell subset in the tacrolimus plus TGP-treated group was lower than that in the tacrolimus-treated group (P<0.05). The level of CD8(+) T cell subset and the hepatic and renal function had no significant differences between the tacrolimus-treated group and the tacrolimus plus TGP-treated group. CONCLUSION: Effects of tacrolimus plus TGP in prevention of rejection are better than tacrolimus monotherapy in rats with cardiac allograft and without increasing side effects.

4.
Chinese Journal of Diabetes ; (12): 233-234, 2006.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-423604

RESUMO

The pancreatic islet cell and testicular sertoli cells of rat were alone-and co-microencapsulated and cultured for 11 days, then insulin concentration of culture fluid was detected.The results showed that islet function in co-microencapsulated group was better than that in co-culture of microencapsulated islet and microencapsulated testicular sertoli cells and also better than that single microencapsulated islet group (P<0.05).

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-538198

RESUMO

Objective To assess the preventive effects of FK506 and Leflunomide (Lef) on islet xenograft acute rejection in rat-to-mouse models. Methods The islets of rat were transplanted under the kidney capsule of streptozotocin-induced diabetic mouse. The recipients were randomly divided into control group, un-treatment group, mono-therapy group and combination-therapy group. All immunosuppressants were administrated daily from 0 to 9 days. CD4 +\, CD8 + T-cell subsets and IL-2 were examined on the 5?th day after transplantation. Results Compared with un-treatment group, xenoislet survival could be significally prolonged in mono-therapy group. Combination-therapy of FK506 with Lef could significantly prolong the survival of xenoislet when compared with FK506 or Lef used alone. The number of CD4 + T-cells in mono-therapy group and combination-therapy group was much less than in un-treatment group. Conclusion Both FK506 and Lef can suppress proliferation of CD4 + T-cells and prevent or delay islet xenograft rejection.

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