Phase diagram and magnetic excitations of J1J_1-J3J_3 Heisenberg model on the square lattice

We study the phase diagram and the dynamical spin structure factor of the spin-1/2 J1-J3 Heisenberg model on the square lattice using density matrix renormalization group, exact diagonalization (ED), and cluster perturbation theory (CPT). By extrapolating the order parameters and studying the level crossings of the low-lying energy and entanglement spectra, we obtain the phase diagram of this model and identify a narrow region of quantum spin liquid (QSL) phase followed by a plaquette valence-bond solid (PVBS) state in the intermediate region, whose nature has been controversial for many years. More importantly, we use CPT and ED to study the dynamical spin structure factor in the QSL and the PVBS phase. In the QSL phase, the high-energy magnon mode completely turns into some dispersive weak excitations around the X and M points. For the PVBS phase, the low-energy spectrum is characterized by a gapped triplet excitation, and at the high energy, we find another branch of dispersive excitation with broad continua, which is unlike the plaquette phase in the 2x2 checkerboard model. In the latter case, the second branch of excitation is nearly flat due to the weak effective interactions between the local excitations of the plaquettes. And in the J1-J3 Heisenberg model, the uniform interactions and the spontaneously translational symmetry breaking of the PVBS phase make the difference in the excitation spectra.Comment: 14 pages, 14 figure

Haldane phases and phase diagrams of the S = 3/2, 1 bilinear-biquadratic Heisenberg model on the orthogonal dimer chain

We systematically study the effects of higher-order interactions on the S = 3/2, 1 orthogonal dimer chains using exact diagonalization and density matrix renormalization group. Due to frustration and higher spin, there are rich quantum phases, including three Haldane phases, two gapless phases and several magnetically ordered phases. To characterize these phases and their phase transitions, we study various physical quantities such as energy gap, energy level crossing, fidelity susceptibility, spin correlation, entanglement spectrum and central charge. According to our calculations, the biquadratic term can enhance the Haldane phase regions. In particular, we numerically identify that a Haldane phase in S = 3/2 case is adiabatically connected to the exact AKLT point when adding bicubic term. Our study on the orthogonal dimer model, which is a 1D version of Shastry-Sutherland model, provides insights into understanding the possible S = 3/2, 1 Haldane phases in quasi-1D and 2D frustrated magnetic materials.Comment: 14 pages, 17 figure

Deep Time-Stream Framework for Click-Through Rate Prediction by Tracking Interest Evolution

Click-through rate (CTR) prediction is an essential task in industrial applications such as video recommendation. Recently, deep learning models have been proposed to learn the representation of users' overall interests, while ignoring the fact that interests may dynamically change over time. We argue that it is necessary to consider the continuous-time information in CTR models to track user interest trend from rich historical behaviors. In this paper, we propose a novel Deep Time-Stream framework (DTS) which introduces the time information by an ordinary differential equations (ODE). DTS continuously models the evolution of interests using a neural network, and thus is able to tackle the challenge of dynamically representing users' interests based on their historical behaviors. In addition, our framework can be seamlessly applied to any existing deep CTR models by leveraging the additional Time-Stream Module, while no changes are made to the original CTR models. Experiments on public dataset as well as real industry dataset with billions of samples demonstrate the effectiveness of proposed approaches, which achieve superior performance compared with existing methods.Comment: 8 pages. arXiv admin note: text overlap with arXiv:1809.03672 by other author

Experimental study on mixed traffic flow of bicycles and pedestrians

The mixed flow of bicycles and pedestrians is frequently observed on bicycle-pedestrian-shared roads. Unfortunately, studies on dynamics of this kind of mixed flow are very limited. This paper reports an experimental study of this kind of mixed traffic flow with equal numbers of pedestrians and cyclists asked to walk/ride in a ring-shaped track. In the uni-/bi-directional flow scenarios, pedestrians and bicycles moved in the same/opposite direction. Under both scenarios, bicycles and pedestrians formed their own lanes. Pedestrians walked in the inner lane and cyclists rode in the outer lane. Widths of both the pedestrian lane and the bicycle lane were more uniform in bidirectional flow. The pedestrian flow rate is larger in the unidirectional flow scenario than in the bidirectional flow scenario. In contrast, at low densities, the bicycle flow rate is essentially the same under the two scenarios. When the density is large, the bicycle flow rate becomes larger in the unidirectional flow scenario. Comparing the two modes, pedestrian flow rate is smaller/larger than bicycle flow rate at small/large densities under both scenarios

Poly[μ-aqua-diaqua(μ3-1H-benzimid­azole-5-carboxylato-κ3 N 3:O,O′)(μ2-1H-benzimidazole-5-carboxylato-κ3 N 3:O:O′)-μ5-sulfato-μ4-sulfato-tri­cadmium]

The asymmetric unit of the title compound, [Cd3(C8H5N2O2)2(SO4)2(H2O)3]n, contains three CdII ions, two sulfate anions, two 1H-benzimidazole-5-carboxyl­ate (H2bic) ligands and three coordinated water mol­ecules. One CdII ion is six-coordinated and exhibits a distorted octa­hedral geometry, while the other two CdII ions are seven-coordinated, displaying a distorted penta­gonal–bipyramidal geometry. The CdII ions are bridged by two types of sulfate anions, producing inorganic chains along [100]. These chains are further connected by the H2bic ligands, leading to a three-dimensional framework. N—H⋯O and O—H⋯O hydrogen bonds and π–π inter­actions between the imidazole and benzene rings [centroid–centroid distances = 3.953 (2), 3.507 (2), 3.407 (2) and 3.561 (2) Å] further stabilize the crystal structure

A Simplified Rice DNA Extraction Protocol for PCR Analysis

Abstract: A simple protocol was established for DNA extraction using etiolated rice seedlings, whereby rice DNA was directly extracted in 0.5 mol/L NaOH solution in a single eppendorf tube. Results of comparative PCR analyses and electrophoresis showed that the DNA extracted using this method was as good and useful as that using standard CTAB method. Key words: DNA extraction; rice; polymerase chain reaction; molecular marker; simple sequence repeats; transgene DNA molecular marker technology has been advancing rapidly during past decades and its application perspective seems very brilliant in crop breeding, varietal purity test of crop seeds and germplasm fingerprinting MATERIALS AND METHODS Materials Seeds of the following conventional and hybrid rice varieties were used in this study: indica hybrid rice Xieyou 92 (Xieqingzao/Hui 92) F 1 and Xieyou 46 (Xieqingzao A/Milyang 46) F 1 , the cytoplasmic male sterile line Xieqingzao A, the DNA extraction DNA was extracted using a modified CTAB method PCR and products analysis PCR amplification of DNA fragments of the cry1Ab gene in transgenic rice and of the microsatellite within the Wx gene in hybrid rice were conducted using the DNA templates isolated by modified CTAB method and our own simplified protocol. The sequences of forward primer and reverse primer for the cry1Ab gene were 5'-TTCCTTGGACGAAATCCCACC-3' and 5'-GCCAGAATTGAACACATGAGCGC-3', targeting a fragment of 559 bp. The forward primer of SSR of Wx gene was 5'-CTTTGTCTATCTCAAGACAC-3' and the reverse primer 5'-TTGCAGATGTTCTTCCTGATG-3', which were designed according to Blight et a

In2S3 Quantum Dots: Preparation, Properties and Optoelectronic Application

Low-dimensional semiconductors exhibit remarkable performances in many device applications because of their unique physical, electrical, and optical properties. In this paper, we report a novel and facile method to synthesize In2S3 quantum dots (QDs) at atmospheric pressure and room temperature conditions. This involves the reaction of sodium sulfide with indium chloride and using sodium dodecyl sulfate (SDS) as a surfactant to produce In2S3 QDs with excellent crystal quality. The properties of the as-prepared In2S3 QDs were investigated and photodetectors based on the QDs were also fabricated to study the use of the material in optoelectronic applications. The results show that the detectivity of the device stabilizes at ~ 1013 Jones at room temperature under 365 nm ultraviolet light irradiation at reverse bias voltage

The prognostic significance of protein tyrosine phosphatase 4A2 in breast cancer

Duanzheng Zhao,1 Libin Guo,2,* Henrique Neves,3,* Hiu-Fung Yuen,4 Shu-Dong Zhang,5 Cian M McCrudden,6 Qing Wen,5 Jin Zhang,2 Qi Zeng,4 Hang Fai Kwok,3,5,6 Yao Lin2 1College of Continuing Education, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, People’s Republic of China; 2College of Life Sciences, Fujian Normal University, Fuzhou, Fujian, People’s Republic of China; 3Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau Special Administrative Region, People’s Republic of China; 4Institute of Molecular and Cell Biology, Biopolis Drive, Proteos, Singapore; 5Center for Cancer Research and Cell Biology, 6School of Pharmacy, Queen’s University of Belfast, Belfast, UK *These authors have contributed equally to this work Abstract: Although PTP4A3 has been shown to be a very important factor in promoting cancer progression, the role of its close family member PTP4A2 is still largely unknown. Recent reports have shown contradicting results on the role of PTP4A2 in breast cancer progression. Considering this, we aimed to investigate the prognostic value of PTP4A2 in five independent breast cancer data sets (minimum 198 patients per cohort, totaling 1,124 patients) in the Gene Expression Omnibus Database. We found that high expression of PTP4A2 was a favorable prognostic marker in all five independent breast cancer data sets, as well as in the combined cohort, with a hazard ratio of 0.68 (95% confidence interval =0.56–0.83; P<0.001). Low PTP4A2 expression was associated with estrogen receptor-negative tumors and tumors with higher histological grading; furthermore, low expression was inversely correlated with the expression of genes involved in proliferation, including MKI67 and the MCM gene family encoding the minichromosome maintenance proteins. These findings suggest that PTP4A2 may play a role in breast cancer progression by dysregulating cell proliferation. PTP4A2 expression was positively correlated with ESR1, the gene encoding estrogen receptor-alpha, and inversely correlated with EGFR expression, suggesting that PTP4A2 may be involved in these two important oncogenic pathways. Together, our results suggest that expression of PTP4A2 is a favorable prognostic marker in breast cancer. Keywords: breast cancer, PTP4A2, survival, prognostic marker, overexpression, minichromosome maintenance proteins&nbsp

Comparison of Efficacy and Safety Between First and Second Generation Drug-Eluting Stents in Patients with Stable Coronary Artery Disease: A Single-Center Retrospective Study

Background: Lots of trials demonstrate that second-generation drug-eluting stents (G2-DES), with their improved properties, offer significantly superior efficacy and safety profiles compared to first generation DES (G1-DES) for patients with coronary artery disease (CAD) receiving percutaneous coronary intervention (PCI). This study aimed to verify the advantage of G2-DES over G1-DES in Chinese patients with stable CAD (SCAD). Methods: For this retrospective observational analysis, 2709 SCAD patients with either G1-DES (n = 863) or G2-DES (n = 1846) were enrolled consecutively throughout 2013. Propensity score matching (PSM) was applied to control differing baseline factors. Two-year outcomes, including major adverse coronary events as well as individual events, including target vessel-related myocardial infarction, target lesion revascularization (TLR), target vessel revascularization, and cardiogenic death were evaluated. Results: The incidence of revascularization between G1- and G2-DES showed a trend of significant difference with a threshold P - value (8.6% vs. 6.7%, χ2 = 2.995, P = 0.084). G2-DES significantly improved TLR-free survival compared to G1-DES (96.6% vs. 97.9%, P = 0.049) and revascularization-free survival curve showed a trend of improvement of G2-DES (92.0% vs. 93.8%, P = 0.082). These differences diminished after PSM. Multivariate Cox proportional hazard regression analysis showed a trend for G1-associated increase in revascularization (hazard ratio: 1.28, 95% confidence interval: 0.95-1.72, P = 0.099) while no significance was found after PSM. Other endpoints showed no significant differences after multivariate adjustment regardless of PSM. Conclusions: G1-DES showed the same safety as G2-DES in this large Chinese cohort of real-world patients. However, G2-DES improved TLR-free survival of SCAD patients 2 years after PCI. The advantage was influenced by baseline clinical factors. G1-DES was associated with a trend of increase in revascularization risk and was not an independent predictor of worse medium-term prognosis compared with G2-DES