Breaking a novel colour image encryption algorithm based on chaos

Recently, a colour image encryption algorithm based on chaos was proposed by cascading two position permutation operations and one substitution operation, which are all determined by some pseudo-random number sequences generated by iterating the Logistic map. This paper evaluates the security level of the encryption algorithm and finds that the position permutation-only part and the substitution part can be separately broken with only $\lceil (\log_2(3MN))/8 \rceil$ and 2 chosen plain-images, respectively, where $MN$ is the size of the plain-image. Concise theoretical analyses are provided to support the chosen-plaintext attack, which are verified by experimental results also.Comment: 5 pages, 1 figur

The Adsorption of CHS-1 Resin for Cr (VI) of Low Concentration from Electroplating Wastewater

AbstractThe adsorption property of CHS-1 resin for Cr (VI) was investigated by chemical analysis. Experiment results show that CHS-1 resin has the best adsorption ability for Cr (VI) at pH=2-3. The exchange adsorption rate of the resin for Cr (VI) at low concentration is controlled by liquid film diffusion and chemical reaction. The behavior obeys the Freundlich isotherm and Langmuir equation. Its saturated sorption capacity is 347.22mg/g at 298K. The thermodynamic adsorption parameters, enthalpy change ΔH and free energy change ΔG298 of the adsorption are 1.39kJ/mol and -5.3kJ/mol. Cr (VI) adsorbed on CHS-1 resin can be eluted by 5% NaOH -5% NaCl quantitatively without apparent decrease in sorption capacity

Uncertainty analysis on process responses of conventional spinning using finite element method

Conventional spinning is a widely used metal forming process to manufacture rotationally axis-symmetric and asymmetric products. Considerable efforts have been made to investigate the forming quality of spun parts using the process in recent years. However, inherent uncertainty properties involved in the spinning process are rarely considered in previous studies. In this paper, an uncertainty analysis and process optimisation procedure have been developed and implemented on conventional spinning with 3D Finite Element Method (FEM). Three process variables are randomized by Gaussian distribution to study the probabilistic characteristics of two process responses. Linear and quadratic approximate representations are constructed by Monte Carlo based Response Surface Method (RSM) with Latin Hypercube Sampling (LHS). The Most Probable Point (MPP) method, which has been widely used to estimate the failure probability in other applications, is further developed in this paper to obtain the probability distribution of the system responses. Following an evaluation of the system responses conducted by the MPP method, a control variable method is used to reduce the variance of spun part wall thickness and total roller force to satisfy the 3σ quality requirement. This uncertainty analysis and process optimisation procedure can be easily implemented in other metal spinning processes. © 2014 Springer-Verlag Berlin Heidelberg

Expressions of Hippocampal Mineralocorticoid Receptor (MR) and Glucocorticoid Receptor (GR) in the Single-Prolonged Stress-Rats

Post-traumatic stress disorder (PTSD) is a stress-related mental disorder caused by traumatic experience. Single-prolonged stress (SPS) is one of the animal models proposed for PTSD. Rats exposed to SPS showed enhanced inhibition of the hypothalamo-pituitary-adrenal (HPA) axis, which has been reliably reproduced in patients with PTSD. Mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) in the hippocampus regulate HPA axis by glucocorticoid negative feedback. Abnormalities in negative feedback are found in PTSD, suggesting that GR and MR might be involved in the pathophysiology of these disorders

1,2-Bis(4-nitro­benz­yl)diselane

The title compound, C14H12N2O4Se2, is not chiral, but the mol­ecules assume a chiral conformation in the solid state and crystallize as an aggregate. The central C—Se—Se—C torsion angle is 90.4 (2)°, while the two Se—Se—C—C fragments assume gauche conformations with values of −59.4 (5) and 67.5 (4)°. The dihedral angle between the two benzene rings is 80.74 (14)°

Systematic Review on Acupuncture for Treatment of Dysphagia after Stroke

Objective. To assess the therapeutic efficacy of acupuncture for dysphagia after stroke. Methods. Seven electronic databases were searched from their inception until 31 September 2016. All randomized controlled trials (RCTs) incorporating acupuncture or acupuncture combined with other interventions for treatment of dysphagia after stroke were enrolled. Then they were extracted and assessed by two independent evaluators. Direct comparisons were conducted in RevMan 5.3.0 software. Results. 6010 patients of 71 papers were included. The pooled analysis of efficacy rate of 58 studies indicated that acupuncture group was superior to the control group with moderate heterogeneity (RR = 1.17, 95% CI: 1.13 1.21, Z=9.08, and P<0.00001); meta-analysis of the studies using blind method showed that the efficacy rate of acupuncture group was 3.01 times that of control group with no heterogeneity (RR = 3.01, 95% CI: 1.95 4.65, Z=4.97, and P<0.00001). Only 13 studies mentioned the safety evaluation. Conclusion. The result showed that the acupuncture group was better than control group in terms of efficacy rate of dysphagia after stroke. And the combining result of those researches using blind method was more strong in proof. Strict evaluation standard and high-quality RCT design are necessary for further exploration