Experimental study on discretely modulated continuous-variable quantum key distribution

We present a discretely modulated continuous-variable quantum key distribution system in free space by using strong coherent states. The amplitude noise in the laser source is suppressed to the shot-noise limit by using a mode cleaner combined with a frequency shift technique. Also, it is proven that the phase noise in the source has no impact on the final secret key rate. In order to increase the encoding rate, we use broadband homodyne detectors and the no-switching protocol. In a realistic model, we establish a secret key rate of 46.8 kbits/s against collective attacks at an encoding rate of 10 MHz for a 90% channel loss when the modulation variance is optimal.Comment: 7 pages,6 figure

Finding Unsatisfiable Subformulas with Stochastic Method

Abstract. Explaining the causes of infeasibility of Boolean formulas has many practical applications in various fields. A small unsatisfiable subformula provides a succinct explanation of infeasibility and is valuable for applications. In recent years the problem of finding unsatisfiable subformulas has been addressed frequently by research works, which are mostly based on the SAT solvers with DPLL backtrack-search algorithm. However little attention has been concentrated on extraction of unsatisfiable subformulas using stochastic methods. In this paper, we propose a resolution-based stochastic local search algorithm to derive unsatisfiable subformulas. This approach directly constructs the resolution sequences for proving unsatisfiability with a local search procedure, and then extracts small unsatisfiable subformulas from the refutation traces. We report and analyze the experimental results on benchmarks

Equity in use of maternal health services in Western Rural China: a survey from Shaanxi province

BACKGROUND: The 20(th) century was marked by a significant improvement in worldwide human health and access to healthcare. However, these improvements were not completely or uniformly distributed among, or even within, nations. This study was designed to assess the use of maternal health services by pregnant women in China, with a focus on the inequity related to family income level. METHODS: Two population-based cross-sectional surveys were carried out in the Zhenan and Lantian counties in March 2007 and from December 2008 to March 2009. A total of 2562 women completed the questionnaires, including 948 who were pregnant in 2006 and 1614 from 2008–2009. The concentration index (CI) was calculated and used to analyze the parameters of maternal health care in the two counties surveyed. RESULTS: The responses in both 2006 and 2008–2009 indicated a bias towards higher (rich) economic statuses for the use of maternal and child health services. The CI of ‘delivery at health facility’ was 0.0206 (95% confidence interval between 0.0114 and 0.0299) for 2006 and 0.0053 (95% confidence interval between 0.0015 and 0.0091) for 2008, which represented a statistically significant inequity for women of lower (poor) economic statuses. Similar CI was observed in ‘receiving antenatal care within 12 weeks’ for 2006 (CI(2006) = 0.0956, 95% confidence interval between 0.0516 and 0.1396). The CIs of ‘postnatal visit’ and ‘postnatal visit >3-times’ was positive (except for 2006), indicating that the poor used postnatal care less than the non-poor. In 2008, poor women had C-sections more often than non-poor women (CI(2008) = −0.0629, 95% confidence interval between-0.1165 and −0.0093), but such a difference was not observed in 2006. CONCLUSIONS: In 2006 and 2008, the use of maternal health services in western rural China was significantly unequal between pregnant women of poor and non-poor economic statuses. Financial support that enables poorer pregnant women to use health services will be beneficial. Utilization of maternal healthcare services can be improved if out-of-pocket expenses can be minimized

PSAT1 prompted cell proliferation and inhibited cell apoptosis in multiple myeloma through regulating PI3K/AKT pathway

Purpose: To identify the biological function of phosphoserine aminotransferase 1 (PSAT1) in regulating cell proliferation and apoptosis in multiple myeloma (MM).Methods: The mRNA and protein levels of PSAT1 were determined using quantitative real-time polymerase chain reaction (PCR) and western blotting, respectively. Cell proliferation was measured using CCK-8 assay.Results: PSAT1 mRNA and protein expression levels were significantly increased in MM cell lines when compared to control cells. Moreover,  downregulation of PSAT1 inhibited MM cell proliferation and induced cell apoptosis, whereas overexpression of PSAT1 promoted MM cell  proliferation and suppressed cell apoptosis. Further analysis demonstrated that the underlying mechanism was via regulation of PI3K/AKT pathway.Conclusion: The results identified a novel role for PSAT1 in the progression of MM, which may provide a therapeutic and a new anticancer target for the therapy of MM. Keywords: Multiple myeloma, PSAT1, Cell proliferation, PI3K/AKT pathwa

Study of phase transition of Potts model with DANN

A transfer learning method, domain adversarial neural network (DANN), is introduced to study the phase transition of two-dimensional q-state Potts model. With the DANN, we only need to choose a few labeled configurations automatically as input data, then the critical points can be obtained after training the algorithm. By an additional iterative process, the critical points can be captured to comparable accuracy to Monte Carlo simulations as we demonstrate it for q = 3, 5, 7 and 10. The type of phase transition (first or second-order) is also determined at the same time. Meanwhile, for the second-order phase transition at q = 3, we can calculate the critical exponent $\nu$ by data collapse. Furthermore, compared with the traditional supervised learning, the DANN is of higher accuracy with lower cost.Comment: 25 pages, 23 figure

Optimization of bonding parameters of laminated wood using a novel bio-based RPF adhesive

Adhesive is the key component and factor for the manufacture of glulam, affected both the properties and cost of glulam product. Bio-based resorcinol-phenol-formaldehyde (BRPF) resin was developed by partly replacing the expensive resorcinol and phenol with the cheap biomass derived pyrolysis oil. The press process parameters and the dosage of adhesive and corresponding curing agent were selected as the factors and extensively studied. BRPF resin was successfully used to bond the laminas to produce glulam, and the optimized process parameters for the cold-pressing adhesion of BRPF resin with pine wood were obtained as follows: the cold-pressing pressure 1.4 MPa, the cold-pressing time 9 h, the amount of adhesive coating 320 g/m2, and the proportion of curing agent (poly-formaldehyde) 17%. The mechanical performances of laminated wood bonding with BRPF resin under the optimal condition were further verified. It is believed that the results obtained here will promote the use of bio-based resin in the bonding of laminated wood, and then contribute to the green manufacturing of glulam with lower cost

Design Multilayer Antireflection Coatings for Terrestrial Solar Cells

In order to analyze the influence of methods to design antireflection coatings (ARCs) on reflectivity of broadband solar cells, we provide detailed analyses about the ARC coupled with a window layer and the refractive index dispersion effect of each layer. By multidimensional matrix data simulation, two methods were employed to measure the composite reflection of a Si/ZnS double-layer ARC within the spectral ranges of 300–870 nm (dual junction) and 300–1850 nm (triple junction) under AM1.5 solar radiation. A comparison study, between the results obtained from the commonly used weighted average reflectance method (WAR) and that from the introduced effective average reflectance method (EAR), shows that the optimization of ARC by EAR method is convenient and feasible