Valosin-containing protein regulates the proteasome-mediated degradation of DNA-PKcs in glioma cells.

DNA-dependent protein kinase (DNA-PK) has an important role in the repair of DNA damage and regulates the radiation sensitivity of glioblastoma cells. The VCP (valosine-containing protein), a chaperone protein that regulates ubiquitin-dependent protein degradation, is phosphorylated by DNA-PK and recruited to DNA double-strand break sites to regulate DNA damage repair. However, it is not clear whether VCP is involved in DNA-PKcs (DNA-PK catalytic subunit) degradation or whether it regulates the radiosensitivity of glioblastoma. Our data demonstrated that DNA-PKcs was ubiquitinated and bound to VCP. VCP knockdown resulted in the accumulation of the DNA-PKcs protein in glioblastoma cells, and the proteasome inhibitor MG132 synergised this increase. As expected, this increase promoted the efficiency of DNA repair in several glioblastoma cell lines; in turn, this enhanced activity decreased the radiation sensitivity and prolonged the survival fraction of glioblastoma cells in vitro. Moreover, the VCP knockdown in glioblastoma cells reduced the survival time of the xenografted mice with radiation treatment relative to the control xenografted glioblastoma mice. In addition, the VCP protein was also downregulated in ~25% of GBM tissues from patients (WHO, grade IV astrocytoma), and the VCP protein level was correlated with patient survival (R(2)=0.5222, P<0.05). These findings demonstrated that VCP regulates DNA-PKcs degradation and increases the sensitivity of GBM cells to radiation

Synthesis of bismuth ferrite nanoparticles via a wet chemical route at low temperature

2010-2011 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

An Exactly Solvable Model of Generalized Spin Ladder

A detailed study of an $S={1\over2}$ spin ladder model is given. The ladder consists of plaquettes formed by nearest neighbor rungs with all possible SU(2)-invariant interactions. For properly chosen coupling constants, the model is shown to be integrable in the sense that the quantum Yang-Baxter equation holds and one has an infinite number of conserved quantities. The R-matrix and L-operator associated with the model Hamiltonian are given in a limiting case. It is shown that after a simple transformation, the model can be solved via a Bethe ansatz. The phase diagram of the ground state is exactly derived using the Bethe ansatz equation

DaMN – Discriminative and Mutually Nearest: Exploiting Pairwise Category Proximity for Video Action Recognition

We propose a method for learning discriminative category-level features and demonstrate state-of-the-art results on large-scale action recognition in video. The key observation is that one-vs-rest classifiers, which are ubiquitously employed for this task, face challenges in separating very similar categories (such as running vs. jogging). Our proposed method automatically identifies such pairs of categories using a criterion of mutual pairwise proximity in the (kernelized) feature space, using a category-level similarity matrix where each entry corresponds to the one-vs-one SVM margin for pairs of categories. We then exploit the observation that while splitting such Siamese Twin categories may be difficult, separating them from the remaining categories in a two-vs-rest framework is not. This enables us to augment one-vs-rest classifiers with a judicious selection of two-vs-rest classifier outputs, formed from such discriminative and mutually nearest (DaMN) pairs. By combining one-vs-rest and two-vs-rest features in a principled probabilistic manner, we achieve state-of-the-art results on the UCF101 and HMDB51 datasets. More importantly, the same DaMN features, when treated as a mid-level representation also outperform existing methods in knowledge transfer experiments, both cross-dataset from UCF101 to HMDB51 and to new categories with limited training data (one-shot and few-shot learning). Finally, we study the generality of the proposed approach by applying DaMN to other classification tasks; our experiments show that DaMN outperforms related approaches in direct comparisons, not only on video action recognition but also on their original image dataset tasks. © 2014 Springer International Publishing

Robust L2 - L∞ filtering for a class of dynamical systems with nonhomogeneous Markov jump process

This paper investigates the problem of robust L2 - L∞ filtering for a class of dynamical systems with nonhomogeneous Markov jump process. The time-varying transition probabilities which evolve as a nonhomogeneous jump process are described by a polytope, and parameter-dependent and mode-dependent Lyapunov function is constructed for such system, and then a robust L2 -L8 filter is designed which guarantees that the resulting error dynamic system is robustly stochasticallystable and satisfies a prescribed L2 - L∞ performance index. A numerical example is given to illustrate the effectiveness of the developed techniques

A Census of Eddy Activities in the South China Sea During 1993-2007

Numerous mesoscale eddies occur each year in the South China Sea (SCS), but their statistical characteristics are still not well documented. A Pacific basin-wide three dimensional physical-biogeochemical model has been developed and the result in the SCS subdomain is used to quantify the eddy activities during the period of 1993-2007. The modeled results are compared with a merged and gridded satellite product of sea level anomaly by using the same eddy identification and tracking method. On average, there are about 32.9 +/- 2.4 eddies predicted by the model and 32.8 +/- 3.4 eddies observed by satellite each year, and about 52% of them are cyclonic eddies. The radius of these eddies ranges from about 46.5 to 223.5 km, with a mean value of 87.4 km. More than 70% of the eddies have a radius smaller than 100 km. The mean area covered by these eddies each year is around 160,170 km(2), equivalent to 9.8% of the SCS area with water depths greater than 1000 m. Linear relationships are found between eddy lifetime and eddy magnitude and between eddy vertical extent and eddy magnitude, showing that strong eddies usually last longer and penetrate deeper than weak ones. Interannual variations in eddy numbers and the total eddy-occupied area indicate that eddy activities in the SCS do not directly correspond to the El Nino-Southern Oscillation events. The wind stress curls are thought to be an important but not the only mechanism of eddy genesis in the SCS

Meta-analysis: The Effect of Muscle Strength Training on Walking Ability of Patients with Parkinson's Disease

Objective: This Meta-analysis was aimed to systematically studying the effects of muscle strength training on the walking ability like balance ability, mobility ability of Parkinson's disease patients and then provide useful theoretical reference to further researches on exercise treatments on Parkinson’s disease by retrieving and collecting articles about muscle strength training. Methods This literature review was finally determined on searching PubMed, Elsevier, Web of science, China Journal Full-text Database (CNKI), WanFang Data and other Chinese and foreign databases and combined with manual search. The limit of the search time was from the date when the literature was recorded to 2019. A comprehensive collection of randomly controlled trials of muscle strength training on the walking ability of Parkinson's patients was done. Researchers used the Cochrance risk assessment tool to evaluate the methodological quality of the selected articles, and the ReMan 5.3.5 software to statistically process the obtained data. Results A total of 13 RCTs and 627 samples were included in this study. Meta-analysis of BBS balance scale show that MD=4.67 (95%CI, I2=97%, P=0.52) between muscle strength training group and non-exercise intervention group; MD=-2.67 between muscle strength training group and exercise intervention control group (95%CI, I2=7%, P<0.00001); TUGT Meta-analysis show that MD=-1.06 (95%CI, I2=75%, P=0.10) between muscle strength training group and non-exercise intervention group; MD=0.09 (95%CI, I2=0%, P=0.31) between the muscle strength training group and the control group with exercise intervention; 10MWT Meta-analysis show MD=-0.28 (95%CI), I2=98%, P<0.29) between the muscle strength training group and the control group with exercise intervention; Stride length Meta-analysis show MD=-1.85 (95%CI, I2=68%, P=0.63) between the muscle strength training group and the control group without exercise intervention; MD=-1.75 (95%CI, I2=32%, P=0.56) between the muscle strength training group and the control group with exercise intervention; MD=-1.75 (95%CI, I2=32%, P=0.56). Meta-analysis of stride speed show MD=-0.02 (95%CI, I2=0%, P=0.46) between muscle strength training group and control group without exercise intervention; MD=-0.03 (95%CI, I2=35%, P=0.52) between the muscle strength training group and control group with exercise intervention. Conclusion Muscle strength training can significantly improve the balance ability, mobility, and walking ability of Parkinson's disease patients, but it has no significant benefits on improving stride length and walking speed

Performance of the modified Becke-Johnson potential

Very recently, in the 2011 version of the Wien2K code, the long standing shortcome of the codes based on Density Functional Theory, namely, its impossibility to account for the experimental band gap value of semiconductors, was overcome. The novelty is the introduction of a new exchange and correlation potential, the modified Becke-Johnson potential (mBJLDA). In this paper, we report our detailed analysis of this recent work. We calculated using this code, the band structure of forty one semiconductors and found an important improvement in the overall agreement with experiment as Tran and Blaha [{\em Phys. Rev. Lett.} 102, 226401 (2009)] did before for a more reduced set of semiconductors. We find, nevertheless, within this enhanced set, that the deviation from the experimental gap value can reach even much more than 20%, in some cases. Furthermore, since there is no exchange and correlation energy term from which the mBJLDA potential can be deduced, a direct optimization procedure to get the lattice parameter in a consistent way is not possible as in the usual theory. These authors suggest that a LDA or a GGA optimization procedure is used previous to a band structure calculation and the resulting lattice parameter introduced into the 2011 code. This choice is important since small percentage differences in the lattice parameter can give rise to quite higher percentage deviations from experiment in the predicted band gap value.Comment: 10 pages, 2 figures, 5 Table