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With the development of multimedia processing technology, it is becoming much easier to manipulate and tamper with digital video without leaving any visual clues. Because video compression is very common in digital videos, the tamper might employ powerful multimedia deblocking methods to cover up the video tampering traces. Motion JPEG (MJPEG) is one of the most popular video formats, in which each video frame or interlaced field of a digital video sequence is compressed separately as a JPEG image. By splitting the MJPEG video into JPEG image frames, the tamper might employ powerful multimedia deblocking methods to cover up the video tampering traces. To the best our knowledge, there is no existing method for the forensics of deblocking. In this paper, we propose a novel method to detect deblocking, which can automatically learn feature representations based on a deep learning framework. We first train a supervised convolutional neural network (CNN) to learn the hierarchical features of deblocking operations with labeled patches from the training datasets. The first convolutional layer of the CNN serves as the preprocessing module to efficiently obtain the tampering artifacts. Then, we extract the features for an image with the CNN on the basis of a patch by applying a patch-sized sliding-window to scan the whole image. The generated image representation is then condensed by a simple feature fusion technique, i.e., regional pooling, to obtain the final discriminative feature. The experimental results on several public datasets demonstrate the superiority of the proposed scheme.

Background/Aims: Raddeanin A (RA), an active pharmacological ingredient from Anemone raddeana Regel, plays an important role in tumor suppression. In this study, we assessed the potentially therapeutic effect of RA on glioblastoma and its underlying mechanisms. Methods: Cell viability was examined using the MTT assay. Invasive and migratory capacities were examined using Transwell and wound healing assays. Apoptosis was determined by Hoechst staining, flow cytometry, DCFH-fluorescent probe and immunohistochemical staining. Autophagy was detected by transmission electron microscopy and western blotting. A U251 glioma xenograft model was established to evaluate the effect of RA in vivo. Results: The data demonstrated that RA inhibited viability, and abrogated the invasive/migratory abilities of glioblastoma cells. In addition, RA induced apoptosis by reactive oxygen species (ROS)/ Jun N-terminal kinase (JNK) signaling in glioblastoma. Conversely, the antioxidant N-Acetyl-L-cysteine (NAC) and pan-caspase inhibitor z-VAD-fmk attenuated RA-induced apoptosis by scavenging ROS and inactivating caspase-3. Furthermore, the inhibition of autophagy by 3-MA exacerbated apoptosis through ROS generation and JNK phosphorylation. In vivo, RA exhibited a curative effect on U251-derived xenografts in nude mice. Conclusions: The results of this study suggest that RA suppressed the growth of glioblastoma, thus serving as a promising and potential strategy for glioblastoma chemotherapy.

In this paper, an improved pulse width modulation (PWM) method for chopper-cell (or half-bridge)based modular multilevel converters (MMCs) is proposed. This method can generate an output voltage with maximally 2N+1 (where N is the number of submodules in the upper or lower arm of MMC) levels, which is as great as that of the carrier-phase-shifted PWM (CPSPWM) method. However, no phase-shifted carrier is needed. Compared with the existing submodule unified pulse width modulated (SUPWM) method, the level number of the output voltage is almost doubled and the height of the step in the staircase voltage is reduced by 50%. Meanwhile, the equivalent switching frequency in the output voltage is twice that of the conventional SUPWM method. All these features lead to much reduced harmonic content in the output voltage. What is more, the voltages of the submodule capacitors can be well balanced without any close-loop voltage balancing controllers which are mandatory in the CPSPWM schemes. Simulation and experimental results on a MMC-based inverter show validity of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, a novel single-phase five-level inverter is proposed using coupled inductors. This inverter can output five-level voltage with only one dc source. No split of the dc voltage capacitor is needed, totally avoiding the voltage balancing problem in conventional multilevel inverters. The level of the output voltage is only half of the dc-link voltage in all conditions, leading to much reduced dv/dt . This inverter is based on the widely used three-arm power module and the voltage stresses on all the power switches are the same, making it very easy to construct. Operation mechanism of this inverter is analyzed and the possible switching patterns are investigated. Based on these analyses, a novel optimized modulation scheme is presented. With this modulation method, no dc components exist in the inductor currents, which is very helpful for minimization of the inductors. Simulation and experimental results show the validity of the proposed inverter together with the optimized modulation scheme. [ABSTRACT FROM AUTHOR]

The derivation of the equivalent circuit for a single-sided linear induction motor (SLIM) is not straightforward, particularly if it includes longitudinal end effects from the cut-open primary magnetic path, transversal edge effects from the differing widths between the primary lamination and secondary sheet, and half-filled primary slots. This paper proposes an improved series equivalent circuit for this machine. The longitudinal end effects are estimated using three different impedances representing the normal, forward, and backward flux density waves in the air gap, whose two boundary conditions are deduced by introducing the conception of magnetic barrier surface. The transversal edge effects are accounted for by correction coefficient C̅t and air-gap flux density correction coefficient C̅b. Using the series circuit, the performance of the SLIM was assessed in a similar manner to a rotating induction machine. A 4-kW SLIM prototype was tested, which validated the simulation technique. [ABSTRACT FROM AUTHOR]

Abstract-In this paper, the influence of one-sample delay for sampling and computation in digital control on the bandwidth of the inner current loop of a 400-Hz ground power unit (GPU) is analyzed first. The results show that it is difficult and even impossible for high-power 400-Hz GPUs to maintain low total harmonic distortion content in the output voltage with the conventional proportional-integral-based double-loop control. To improve the performance, resonant controllers with parallel structure which are widely used in active power filters are applied to the single-loop control of the 400-Hz GPU. The parameter design criterion for the parallel resonant controllers is discussed in the discrete time domain. Meanwhile, adoption of-proportional gain in the single-loop control is investigated. The results show that it can improve the performance little and may cause instability problems. Comparisons between different control methods for the 400-Hz GPU are also made, and the single-loop control method in this paper seems to be the most suitable one in terms of simplicity and performance. Experiments on a 16-b fixed-point DSP-controlled 90-kVA 400-Hz GPU prototype show satisfactory results of the single-loop method feeding linear/nonlinear and balanced/unbalanced loads. [ABSTRACT FROM AUTHOR]

Background/Aims: Glioma is the most devastating cancer in the brain and has a poor prognosis in adults. Therefore, there is a critical need for novel therapeutic strategies for the management of glioma patients. Isogambogenic acid, an active compound extracted from the Chinese herb Garcinia hanburyi, induces autophagic cell death. Methods: Cell viability was detected with MTT assays. Cell proliferation was assessed using the colony formation assay. Morphological changes associated with autophagy and apoptosis were tested by TEM and Hoechst staining, respectively. The apoptosis rate was measured by flow cytometry. Western blot, immunofluorescence and immunohistochemical analyses were used to detect protein expression. U87-derived xenografts were established for the examination of the effect of isogambogenic acid on glioma growth in vivo. Results: Isogambogenic acid induced autophagic death in U87 and U251 cells, and blocking late-stage autophagy markedly enhanced the antiproliferative activities of isogambogenic acid. Moreover, we observed the activation of AMPK-mTOR signalling in isogambogenic acid-treated glioma cells. Furthermore, the activation of AMPK or the inhibition of mTOR augmented isogambogenic acid-induced autophagy. Inhibition of autophagy attenuated apoptosis in isogambogenic acid-treated glioma cells. Finally, isogambogenic acid inhibited the growth of U87 glioma in vivo. Conclusion: Isogambogenic acid inhibits the growth of glioma via activation of the AMPK-mTOR signalling pathway, which may provide evidence for future clinical applications in glioma therapy.

Exploring electric field controlled magnetism enables high efficiency and low energy consumption spintronic devices. Here, by manipulating oxygen vacancies and magnetic moment, the authors achieve voltage control of magnetic interlayer coupling in GdOxbased magnetic tunnel junctions.

Meconopsis Vig. is a genus possessing important medicinal and ornamental values in the Papaveraceae. Many species in this genus are commonly used in traditional Tibetan medicines over thousands of years. In this study, we reported the complete chloroplast genome sequence of Meconopsis punicea. Total lengths of the chloroplast genomes were 152,933 bp. The genome had typical quadripartite structure, LSC region (83,031 bp) and SSC region (17,920 bp) were separated by a pair of IRs (25,991 bp), respectively. Moreover, they were composed of 131 genes, including 86 protein coding genes, 37 tRNA genes, 8 rRNA genes and one pseudogene. Phylogenetic analysis based on complete chloroplast genomes showed that M. integrifolia had closer relationship with M. punicea; meanwhile, Meconopsis was closely related to Papaver in Papaveraceae.

The quantum spin liquid (QSL) state is an exotic state of matter featuring a high degree of entanglement and lack of long-range magnetic order in the zero-temperature limit. The triangular antiferromagnet YbMgGaO_{4} is a candidate QSL host, and precise determination of the Hamiltonian parameters is critical to understanding the nature of the possible ground states. However, the presence of chemical disorder has made directly measuring these parameters challenging. Here we report neutron scattering and magnetic susceptibility measurements covering a broad range of applied magnetic field at low temperature. Our data shows a field-induced crossover in YbMgGaO_{4}, which we reproduce with complementary classical Monte Carlo and density matrix renormalization group simulations. Neutron scattering data above and below the crossover reveal a shift in scattering intensity from M to K points and, collectively, our measurements provide essential characteristics of the phase crossover that we employ to strictly constrain proposed magnetic Hamiltonian parameters despite the chemical disorder. Constrained exchange parameters further suggest the material's proximity to the QSL state in the clean limit. More broadly, our approach demonstrates a means of pursuing QSL candidates where Hamiltonian parameters might otherwise be obscured by disorder.

The van der Waals compound, MnBi_{2}Te_{4}, is the first intrinsic magnetic topological insulator, providing a materials platform for exploring exotic quantum phenomena such as the axion insulator state and the quantum anomalous Hall effect. However, intrinsic structural imperfections lead to bulk conductivity, and the roles of magnetic defects are still unknown. With higher concentrations of the same types of magnetic defects, the isostructural compound MnSb_{2}Te_{4} is a better model system for a systematic investigation of the connections among magnetism, topology, and lattice defects. In this work, the impact of antisite defects on the magnetism and electronic structure is studied in MnSb_{2}Te_{4}. Mn-Sb site mixing leads to complex magnetic structures and tunes the interlayer magnetic coupling between antiferromagnetic and ferromagnetic. The detailed nonstoichiometry and site mixing of MnSb_{2}Te_{4} crystals depend on the growth parameters, which can lead to ≈40% of Mn sites occupied by Sb and ≈15% of Sb sites by Mn in as-grown crystals. Single-crystal neutron diffraction and electron microscopy studies show nearly random distribution of the antisite defects. Band structure calculations suggest that the Mn-Sb site mixing favors a ferromagnetic interlayer coupling, consistent with experimental observation, but is detrimental to the band inversion required for a nontrivial topology. Our results suggest a long-range magnetic order of Mn ions sitting on Bi sites in MnBi_{2}Te_{4}. The effects of site mixing should be considered in all layered heterostructures that consist of alternating magnetic and topological layers, including the entire family of MnTe(Bi_{2}Te_{3})_{n}, its Sb analogs, and their solid solution.

Measurement accuracy is an important performance indicator for high-voltage direct current (HVDC) voltage dividers. The temperature rise effect for a HVDC voltage divider’s internal resistance has an adverse effect on measurement accuracy. In this paper, by building a solid model of a DC voltage divider, the internal temperature rise characteristic and error caused by the temperature rise in a resistance voltage divider were theoretically simulated. We found that with the increase in height and working time, the internal temperature of the voltage divider increased. The results also showed that the lowest temperature was near the lower flange and the highest temperature was near the upper flange in the middle of the voltage divider. The error caused by the temperature rise increased first and then decreased gradually with divider height, increasing with its working time. The measurement error caused by the internal temperature difference in steady state reached a maximum of 158.4 ppm. This study provides a theoretical basis to determine the structure and accuracy improvement for a resistive voltage divider, which is helpful for the selection of components and the optimization of the heat dissipation structure.

Background/Aims: Glioblastoma multiforme (GBM) is the most malignant primary brain tumor with a poor prognosis. Combination treatment of autophagy inducer and autophagy inhibitor may be a feasible solution to improve the therapeutic effects. However, the correlation between them is unclear. The purpose of this study was to investigate the effect of autophagy inhibition at different stages on cytotoxicity of autophagy inducers in glioblastoma cells. Methods: Autophagy inhibition at early stage was achieved by 3-methyladenine (3-MA) or Beclin 1 shRNA. Autophagy inhibition at late stage was achieved by chloroquine (CQ) or Rab7 shRNA. Cell viability was assessed by MTT assay. Autophagy was measured using transmission electron microscopy and western blot. Apoptosis was measured using western blot and flow-cytometry. Results: Inhibition of early steps of autophagy by 3-MA or Beclin 1 knockdown decreased the toxic effect of arsenic trioxide (ATO) in GBM cell lines. In contrast, blockade of autophagy flux at late stage by CQ or Rab7 knockdown enhanced the cytotoxicity of ATO, and caused accumulation of degradative autophagic vacuoles and robust apoptosis. Moreover, depletion of Beclin 1 abolished the synergistic effect of ATO and CQ by reducing autophagy and apoptosis. Combination of CQ with other autophagy inducers also induced synergistic apoptotic cell death. Conclusion: These results suggest that inhibition of late process of autophagy, not initial step, increases the cytotoxic effect of autophagy inducers via autophagy and apoptosis, which may contribute to GBM chemotherapy.

We report the fabrication of a set of new rare-earth-free magnetic compounds, which form the Fe3Co3Ti2-type hexagonal structure with P-6m2 symmetry. Neutron powder diffraction shows a significant Fe/Co anti-site mixing in the Fe3Co3Ti2 structure, which has a strong effect on the magnetocrystalline anisotropy as revealed by first-principle calculations. Increasing substitution of Fe atoms for Co in the Fe3Co3Ti2 lattice leads to the formation of Fe4Co2Ti2, Fe5CoTi, and Fe6Ti2 with significantly improved permanent-magnet properties. A high magnetic anisotropy (13.0 Mergs/cm3) and saturation magnetic polarization (11.4 kG) are achieved at 10 K by altering the atomic arrangements and decreasing Fe/Co occupancy disorder.

In artificial multiferroics hybrids consisting of ferromagnetic La0.7Sr0.3MnO3 (LSMO) and ferroelectric BaTiO3 epitaxial layers, net Ti moments are found from polarized resonant soft x-ray reflectivity and absorption. The Ti dichroic reflectivity follows the Mn signal during the magnetization reversal, indicating exchange coupling between the Ti and Mn ions. However, the Ti dichroic reflectivity shows stronger temperature dependence than the Mn dichroic signal. Besides a reduced ferromagnetic exchange coupling in the interfacial LSMO layer, this may also be attributed to a weak Ti-Mn exchange coupling that is insufficient to overcome the thermal energy at elevated temperatures.

We observe current induced spin transfer torque resonance in permalloy (Py) grown on monolayer MoS2. By passing rf current through the Py/MoS2 bilayer, field-like and damping-like torques are induced which excite the ferromagnetic resonance of Py. The signals are detected via a homodyne voltage from anisotropic magnetoresistance of Py. In comparison to other bilayer systems with strong spin-orbit torques, the monolayer MoS2 cannot provide bulk spin Hall effects and thus indicates the purely interfacial nature of the spin transfer torques. Therefore our results indicate the potential of two-dimensional transition-metal dichalcogenide for the use of interfacial spin-orbitronics applications.

BACKGROUND: We performed a systematic review and meta-analysis to address the (added) value of intraoperative 5-aminolevulinic acid (5-ALA)-guided resection of high-grade malignant gliomas compared with conventional neuronavigation-guided resection, with respect to diagnostic accuracy, extent of tumor resection, safety, and survival. METHODS AND FINDINGS: An electronic database search of Medline, Embase, and the Cochrane Library was undertaken. The review process followed the guidelines of the Cochrane Collaboration. 10 studies matched all selection criteria, and were thus used for qualitative synthesis. 5-ALA-guided resection demonstrated an overall sensitivity of 0.87 (95% confidence interval [CI], 0.81-0.92), specificity of 0.89 (95% CI, 0.79-0.94), positive likelihood ratio (LR) of 7.62 (95% CI, 3.87-15.01), negative LR of 0.14 (95% CI, 0.09-0.23), and diagnostic odds ratio (OR) of 53.06 (95% CI, 18.70-150.51). Summary receiver operating characteristic curves (SROC) showed an area under curve (AUC) of 94%. Contrast-enhancing tumor was completely resected in patients assigned 5-ALA as compared with patients assigned white light. Patients in the 5-ALA group had higher 6-month progression free survival and overall survival than those in the white light group. CONCLUSION: Based on available literature, there is level 2 evidence that 5-ALA-guided surgery is more effective than conventional neuronavigation-guided surgery in increasing diagnostic accuracy and extent of tumor resection, enhancing quality of life, or prolonging survival in patients with high-grade malignant gliomas.

The title compound, C14H12N4O6·C3H7NO, is a monoclinic polymorph of an already published structure [Baughman et al. (2004). Acta Cryst. C60, 103–106]. In the previously reported structure, the compound crystallized in the triclinic space group Poverline{1} (Z = 2), whereas the structure reported here is monoclinic (P21/n, Z = 4). In both forms, two intramolecular hydrogen bonds result in the formation of a fairly planar hydrazone skeleton (r.m.s. deviations for all non-H atoms = 0.127 Å for the monoclinic from and 0.131 Å for the triclinic form) and each molecule is hydrogen bonded to one solvent molecule. The principal difference between the two forms lies in the different orientation of the two molecules. In the monoclinic form, the two molecules are almost coplanar [dihedral angle = 3.27 (2)°], whereas in the triclinic form the two molecules are almost mutulally perpendicular (dihedral angle = 85.3°).

BACKGROUND:Environmental changes, air pollution and ozone depletion are increasing oxidative stress, and global warming threatens health by heat stress. We now face a high risk of simultaneous exposure to heat and oxidative stress. However, there have been few studies investigating their combined adverse effects on cell viability. PRINCIPAL FINDINGS:Pretreatment of hydrogen peroxide (H(2)O(2)) specifically and highly sensitized cells to heat stress, and enhanced loss of mitochondrial membrane potential. H(2)O(2) exposure impaired the HSP40/HSP70 induction as heat shock response (HSR) and the unfolded protein recovery, and enhanced eIF2alpha phosphorylation and/or XBP1 splicing, land marks of ER stress. These H(2)O(2)-mediated effects mimicked enhanced heat sensitivity in HSF1 knockdown or knockout cells. Importantly, thermal preconditioning blocked H(2)O(2)-mediated inhibitory effects on refolding activity and rescued HSF1 +/+ MEFs, but neither blocked the effects nor rescued HSF1 -/- MEFs. These data strongly suggest that inhibition of HSR and refolding activity is crucial for H(2)O(2)-mediated enhanced heat sensitivity. CONCLUSIONS:H(2)O(2) blocks HSR and refolding activity under heat stress, thereby leading to insufficient quality control and enhancing ER stress. These uncontrolled stress responses may enhance cell death. Our data thus highlight oxidative stress as a crucial factor affecting heat tolerance.

An abstract of the article "C-Terminal Part of Alpha-Synuclein Mediates its Activity in Promoting Proliferation of Dopaminergic Cells," by Juanjuan Yin, Tao Wang, Junyan Han, Chen Zhang, Qiulan Ma, Xin Li, Furong Cheng, Yaohua Li, Guangwei Liu, Piu Chan, and colleagues, is presented.

Cotton fiber is a raw material for the global textile industry and fiber quality is essential to its industrial application. Carotenoids are plant secondary metabolites that may serve as dietary components, regulate light harvesting, and scavenge reactive oxygen species. Although carotenoids accumulate predominantly in rapidly elongating cotton fibers, their roles in cotton fiber development remain poorly understood. In this study, a fiber-specific promoter proSCFP was applied to drive the expression of GhOR1Del, a positive regulator of carotenoid accumulation, to upregulate the carotenoid level in cotton fiber in planta. Fiber length, strength, and fineness were increased in proSCFP:GhOR1Del transgenic cotton and abscisic acid (ABA) and ethylene contents were increased in elongating fibers. The ABA downstream regulator GhbZIP27a stimulated the expression of the ethylene synthase gene GhACO3 by binding to its promoter, suggesting that ABA promoted fiber elongation by increasing ethylene production. These findings suggest the involvement of carotenoids and ABA signaling in promoting cotton fiber elongation and provide a strategy for improving cotton fiber quality. [ABSTRACT FROM AUTHOR]

Although the onset time of chemical reactions can be manipulated by mechanical, electrical, and optical methods, its chemical control remains highly challenging. Herein, we report a chemical timer approach for manipulating the emission onset time of chemiluminescence (CL) reactions. A mixture of Mn2+, NaHCO3, and a luminol analog with H2O2 produced reactive oxygen species (ROS) radicals and other superoxo species (superoxide containing complex) with high efficiency, accompanied by strong and immediate CL emission. Surprisingly, the addition of thiourea postponed CL emission in a concentration-dependent manner. The delay was attributed to a slow-generation-scavenging mechanism, which was found to be generally applicable not only to various types of CL reagents and ROS radical scavengers but also to popular chromogenic reactions. The precise regulation of CL kinetics was further utilized in dynamic chemical coding with improved coding density and security. This approach provides a powerful platform for engineering chemical reaction kinetics using chemical timers, which is of application potential in bioassays, biosensors, CL microscopic imaging, microchips, array chips, and informatics. [ABSTRACT FROM AUTHOR]