Controlling transition probability from matter-wave soliton to chaos

For a Bose-Einstein condensate loaded into a weak traveling optical superlattice it is demonstrated that under a stochastic initial set and in a given parameter region the solitonic chaos appears with a certain probability. Effects of the lattice depths and wave vectors on the chaos probability are investigated analytically and numerically, and different chaotic regions associated with different chaos probabilities are found. The results suggest a feasible method for eliminating or strengthening chaos by modulating the moving superlattice experimentally.Comment: 4 pages, 2 figure

Chaotic shock waves of a Bose-Einstein condensate

It is demonstrated that the well-known Smale-horseshoe chaos exists in the time evolution of the one-dimensional Bose-Einstein condensate (BEC) driven by the time-periodic harmonic or inverted-harmonic potential. A formally exact solution of the time-dependent Gross-Pitaevskii equation is constructed, which describes the matter shock waves with chaotic or periodic amplitudes and phases. When the periodic driving is switched off and the number of condensed atoms is conserved, we obtained the exact stationary states and non-stationary states. The former contains the stable non-propagated shock wave, and in the latter the shock wave alternately collapses and grows for the harmonic trapping or propagates with exponentially increased shock-front speed for the antitrapping. It is revealed that existence of chaos play a role for suppressing the blast of matter wave. The results suggest a method for preparing the exponentially accelerated BEC shock waves or the stable stationary states.Comment: 5 pages, 1 figure

Discrete chaotic states of a Bose-Einstein condensate

We find the different spatial chaos in a one-dimensional attractive Bose-Einstein condensate interacting with a Gaussian-like laser barrier and perturbed by a weak optical lattice. For the low laser barrier the chaotic regions of parameters are demonstrated and the chaotic and regular states are illustrated numerically. In the high barrier case, the bounded perturbed solutions which describe a set of discrete chaotic states are constructed for the discrete barrier heights and magic numbers of condensed atoms. The chaotic density profiles are exhibited numerically for the lowest quantum number, and the analytically bounded but numerically unbounded Gaussian-like configurations are confirmed. It is shown that the chaotic wave packets can be controlled experimentally by adjusting the laser barrier potential.Comment: 7 pages, 5 figure

Calcium-binding protein S100P promotes tumor progression but enhances chemosensitivity in breast cancer

Background: Chemoresistance remains one of the obstacles to overcome in the treatment of breast cancer. S100 calcium-binding protein P (S100P) has been observed to be overexpressed in several cancers and has been associated with drug resistance, metastasis, and prognosis. However, the role of S100P in chemoresistance in breast cancer has not been thoroughly determined. Methods: Immunohistochemistry was used to evaluate the expression level of S100P protein in 22 pairs (pre-chemo and post-chemo) of breast cancer tissue from patients who underwent neoadjuvant chemotherapy. The influence of S100P on the biological behavior and chemosensitivity of breast cancer cells was then investigated. Results: The protein level of S100P in breast cancer tissue was significantly higher than in benign fibroadenoma (p<0.001). The S100P expression level was shown to be decreased by 46.55% after neoadjuvant chemotherapy (p=0.015). Subgroup analysis revealed that S100P reduction (57.58%) was mainly observed in the HER2+ tumors (p=0.027). Our in-vitro experiments showed that the knockdown of S100P suppressed the proliferation, adhesion, migration and invasion abilities of T47D and SK-BR-3 breast cancer cells. We further demonstrated that this knockdown increased the chemoresistance to paclitaxel and cisplatin in SK-BR-3 cells. We found that S100P exerted its function by activating NF-κB, CCND1 and Vimentin, but downregulating E-cadherin. Conclusions: S100P promotes the aggressive properties of breast cancer cells and may be considered as a promising therapeutic target. Moreover, S100P can be used to predict the therapeutic effect of chemotherapy in HER2+ breast cancer patients

Paramagnetic behaviour of silver nanoparticles generated by decomposition of silver oxalate

Silver oxalate Ag2C2O4, was already proposed for soldering applications, due to the formation when it is decomposed by a heat treatment, of highly sinterable silver nanoparticles. When slowly decomposed at low temperature (125 °C), the oxalate leads however to silver nanoparticles isolated from each other. As soon as these nanoparticles are formed, the magnetic susceptibility at room temperature increases from -3.14 10-7 emu.Oe-1.g-1 (silver oxalate) up to -1.92 10-7 emu.Oe-1.g-1 (metallic silver). At the end of the oxalate decomposition, the conventional diamagnetic behaviour of bulk silver, is observed from room temperature to 80 K. A diamagnetic-paramagnetic transition is however revealed below 80 K leading at 2 K, to silver nanoparticles with a positive magnetic susceptibility. This original behaviour, compared to the one of bulk silver, can be ascribed to the nanometric size of the metallic particles

Tim-3 promotes cell aggressiveness and paclitaxel resistance through the NF-κB /STAT3 signalling pathway in breast cancer cells

Objective: Although T-cell immunoglobulin and mucin-domain containing molecule-3 (Tim-3) has been recognized as a promising target for cancer immunotherapy, its exact role in breast cancer has not been fully elucidated. Methods: Tim-3 gene expression in breast cancer and its prognostic significance were analyzed. Associated mechanisms were then explored in vitro by establishing Tim-3-overexpressing breast cancer cells. Results: In a pooled analysis of The Cancer Genome Atlas (TCGA) database, Tim-3 gene expression levels were significantly higher (P<0.001) in breast cancer tissue, compared with normal tissues. Tim-3 was a prognosis indicator in breast cancer patients [relapse-free survival (RFS), P=0.004; overall survival (OS), P=0.099]. Tim-3 overexpression in Tim-3low breast cancer cells promoted aggressiveness of breast cancer cells, as evidenced by enhanced proliferation, migration, invasion, tight junction deterioration and tumor-associated tubal formation. Tim-3 also enhanced cellular resistance to paclitaxel. Furthermore, Tim-3 exerted its function by activating the NF-κB/STAT3 signalling pathway and by regulating gene expression [cyclin D1 (CCND1), C-Myc, matrix metalloproteinase-1(MMP1), TWIST, vascular endothelial growth factor (VEGF) upregulation, concomitant with E-cadherin downregulation). Lastly, Tim-3 downregulated tight junction-associated molecules zona occludens (ZO)-2, ZO-1 and occludin, which may further facilitate tumor progression. Conclusions: Tim-3 plays an oncogenic role in breast cancer and may represent a potential target for antitumor therapy

Physical review indexes

The independent directors of a board can impact CEO payperformancemore effectively if a compensation committeeprovides information and assist them in designing relevantexecutive pay schemes. On the basis of this idea, we developed andtested the hypotheses that Chinese firms with a compensationcommittee have a closer CEO pay link with performance when alarger proportion of independent directors serves on the board. Wefocused primarily on the effect of a compensation committee onCEO pay-performance relation as a consequence of its help for theboard and found that board independence produces a strongerrelationship between executive compensation and firmperformance in Chinese listed firms. This association is more evidentin those firms which have a compensation committee. Our findingssuggest that the interaction between independent directors on theboard and a compensation committee has important consequencesfor CEO incentive systems as well as corporate governancestructures in China

Compilation of Bilateral Trade Database by Industry and End-Use Category

During the last decade, the volume of international trade has increased significantly as international economic integration has deepened, especially in emerging countries, and national industrial structures have become increasingly aligned with international trade in intermediate goods. The OECD STAN Bilateral Trade Database by Industry and End-use Category (BTDIxE) presents international trade in goods flows broken down both by industry sectors and by end-use categories, allowing insights into the patterns of trade in intermediate goods between countries to track global production networks and supply chains as well as helping to address other trade-related policy issues such as trade in value added and tasks.global value chains, trade in intermediates, trade statistics

Suppression of Crosstalk in Quantum Circuit Based on Instruction Exchange Rules and Duration

Crosstalk is the primary source of noise in quantum computing equipment. The parallel execution of multiple instructions in quantum computation causes crosstalk, which causes coupling between signal lines and mutual inductance and capacitance between signal lines, destroying the quantum state and causing the program to fail to execute correctly. Overcoming crosstalk is a critical prerequisite for quantum error correction and large-scale fault-tolerant quantum computing. This paper provides an approach for suppressing crosstalk in quantum computers based on multiple instruction exchange rules and duration. Firstly, for the majority of the quantum gates that can be executed on quantum computing devices, a multiple instruction exchange rule is proposed. The multiple instruction exchange rule reorders quantum gates in quantum circuits and separates double quantum gates with high crosstalk on quantum circuits. Then, time stakes are inserted based on the duration of different quantum gates, and quantum gates with high crosstalk are carefully separated in the process of quantum circuit execution by quantum computing equipment to reduce the influence of crosstalk on circuit fidelity. Several benchmark experiments verify the proposed method’s effectiveness. In comparison to previous techniques, the proposed method improves fidelity by 15.97% on average