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The interaction of brilliant green with herring sperm DNA was investigated in detail by spectrometric methods in γ-cyclodextrin systems. On the condition of physiological pH, brilliant green prefers to form the 1:1 inclusion complex with γ-cyclodextrin.All the evidences indicated that the binding modes between γ-cyclodextrin-brilliant green and DNA were grooving binding and partial non-classical intercalative binding. The binding ratio of the inclusion complex with DNA is 6:1. The calculated thermodynamic parameters suggested that the binding of the inclusion complex to DNA was driven mainly by entropy.

This paper proposes a new belief rule-based (BRB) expert system for fault diagnosis of marine diesel engines. The expert system is the first of its kind that consists of multiple concurrently activated BRB subsystems, in which each subsystem has its distinctive outputs and uses the evidential reasoning approach for inference. This novel modeling approach can be applied to identify fault modes that may co-exist. In essence, the group of BRB subsystems is used to model the nonlinear relationships between the fault features and the fault modes in marine diesel engines. The initial BRB expert system can be established by using expert experience and then optimized by using the data samples accumulated during the operation of marine diesel engines. Due to limitations in knowledge and data collected, ignorance is also considered in some BRB subsystems. The proposed BRB expert system is applied to abnormal wear detection for a kind of marine diesel engine. The performance of the BRB expert system is investigated in comparison with that of artificial neural network (ANN) models, support vector machine (SVM) models, and binary logistic regression model with fivefold cross-validation. The results show that the BRB expert system can be used for fault diagnosis of marine diesel engines in a probabilistic manner, which outperforms the ANN models, SVM models, and the binary logistic regression model in terms of accuracy and stability, and can effectively identify concurrent faults. [ABSTRACT FROM AUTHOR]

Based on the recently proposed power-law spectrum for oceanic turbulence [Opt. Express 26 , 10188 (2018)] and the Rytov approximation, the new and exact theoretical forms for the wave structure function (WSF) of plane and spherical waves propagating in turbulent ocean are derived. To make the results easy to use, the simple formulas for the WSF and the associated spatial coherence radius in certain asymptotic regimes are also developed. Through numerical analysis, it is found that the existing results based on the Nikishov's spectrum predict a higher values for the WSF and thus a lower values for the spatial coherence radius than our results. [ABSTRACT FROM AUTHOR]

Recent studies have shown that targeting doxorubicin to mitochondria of tumor cells can bypass the multi-drug resistance problem and inhibit tumor growth. We previously discovered that the C-9th and C-13th position-alkylated berberine derivatives possess improved mitochondria-targeting activity compared to berberine. Therefore, we hypothesize that these alkylated berberine derivatives could be utilized as potential mitochondrial-targeting ligands by inserting the alkyl chain into the liposomal bilayer membrane during the preparation of liposomes. In this research, a berberine derivate (a 16-carbon aliphatic chain was introduced to the C-9th of berberine, 9-C16 berberine) was employed to prepare mitochondria-targeting doxorubicin-loaded folic acid-conjugated polyethylene glycol(PEGylated) liposomes (MT-FOL-PLS). The results of in vitro cytotoxicity and apoptosis-inducing studies revealed that MT-FOL-PLS showed the strongest cytotoxicity and apoptosis-inducing effects in drug resistant MCF-7/adr cells in comparison with free doxorubicin and regular liposomal doxorubicin. MT-FOL-PLS enhanced cellular uptake of doxorubicin up to 15-fold compared to free doxorubicin, and targeted doxorubicin to mitochondria. In vivo and ex vivo drug distribution studies showed that MT-FOL-PLS increased the drug distribution in tumor and the administration of MT-FOL-PLS to resistant MCF-7/adr cell mouse xenografts stopped tumor growth. Our results confirmed that alkylated berberines can be exploited as mitochondrial-targeting ligands to overcome cancer multi-drug resistance, further advancing the research on active targeting of liposome delivery systems in the treatment of resistant cancer. [ABSTRACT FROM AUTHOR]

A series of new cadmium complexes (dyes1–5) were obtained by assembly of the donor–bridge–acceptor (D–π–A)-type ligand (L: 4′-(4-[4-(imidazole)styryl]phenyl) 2,2′ : 6′,2″-terpyridine) with CdX2(X=Cl, Br, I, NCS, ClO4), in which dye3was characterized by single crystal X-ray diffraction. Various weak interactions, including hydrogen bonds (C–H⋯N, C–H⋯X) and π–π interactions, played significant roles in the final topological structures. Linear and non-linear optical properties of ligand and the complexes were investigated. The two-photon absorption cross-section of these complexes are larger than that of ligand with maximum values of 577 GM (dye1), 242 GM (dye2), 171 GM (dye3), 326 GM (dye4), and 215 GM (dye5) in N,N-dimethylformamide. [ABSTRACT FROM AUTHOR]

Ultraviolet-visible (UV-vis) spectra, fluorescence spectra, electrochemistry, and the thermodynamic method were used to discuss the interaction mode between the inclusion complex of hematoxylin with β-cyclodextrin and herring sperm DNA. On the condition of physiological pH, the result showed that hematoxylin and β-cyclodextrin formed an inclusion complex with binding ratio nhematoxylin:nβ-cyclodextrin = 1:1. The interaction mode between β-cyclodextrin-hematoxylin and DNA was a mixed binding, which contained intercalation and electrostatic mode. The binding ratio between β-cyclodextrin-hematoxylin and DNA was nβ-cyclodextrin -hematoxylin:nDNA = 2:1, binding constant was K⊖298.15K = 5.29 × 104 L·mol-1, and entropy worked as driven force in this action. [ABSTRACT FROM AUTHOR]

This article presents the important research findings of our study on whether delayed retirement will affect the health of Chinese workers from the perspective of sustainability of physical health. The treatment group is those who continue to work after the current statutory retirement age and the control group are those who no longer work after current statutory retirement age, and the physical health of these people is used as a dependent variable. The samples are selected from the following six regions of China: Shanghai, Chengdu, Guangzhou, Beijing, Zhengzhou, and Shenyang. Quantitative studies of physical health status of the samples are carried out. The study illustrates that for female manual workers who are younger than 63 years old, female non-manual workers who are younger than 66 years old, male manual workers who are younger than 64 years old, and male non-manual workers who are younger than 67 years old, delaying retirement, and continuing to stay in work has no effect on their physical health. After these chronological age stages, however, it has significant impact on their health. These research findings have significant impact and value for the design of China's delayed retirement policy. [ABSTRACT FROM AUTHOR]

The water-lubricated thrust bearings of the marine Rim-Driven Thruster (RDT) are usually composed of polymer composites, which are prone to serious wear under harsh working conditions. Ultrasonic is an excellent non-destructive monitoring technology, but polymer materials are characterized by viscoelasticity, heterogeneity, and large acoustic attenuation, making it challenging to extract ultrasonic echo signals. Therefore, this paper proposes a wear monitoring method based on an improved ultrasonic reflection coefficient amplitude spectrum, introducing an ultrasonic transfer function to mathematically resolve the attenuation coefficients in the propagation model, and using a differential evolutionary algorithm to invert the thickness, sound velocity, density, and attenuation coefficients of polymer bearings simultaneously. The effects of different influencing factors on the ultrasonic signal and identification results are explored, including probe contact pressure, surface roughness and surface inclination; In order to remove the influence of water film overlap on the identification of polymer bearing thickness, a water film separation method based on time-frequency domain ultrasonic reconfiguration is proposed to construct the ultrasonic theoretical time domain waveform of the bearing. An ultrasonic wear measurement system is built to record the ultrasonic echoes of PEEK test blocks with different pressures to the probe, surface roughness, and tilt angles. The experiment is carried out on the water film calibration test rig, using a high-precision spiral micrometer to simulate the mixing of water films of different thicknesses with polymer test block and collecting ultrasonic signals. The results show that the method has a thickness identification error of approximately 0.5% for PEEK specimens with different probe contact pressure, roughness, and tilt angle, and the reconfiguration thickness identification error is less than 1% for the full range of water film overlap. • Propose a wear monitoring method based on an improved ultrasonic reflection coefficient amplitude spectrum, introducing an ultrasonic transfer function to mathematically resolve the attenuation coefficients in the propagation model. • A water film separation method based on time-frequency domain ultrasonic reconfiguration is proposed to construct the ultrasonic theoretical time domain waveform of the bearing. • Use a differential evolutionary algorithm to invert the thickness, sound velocity, density, and attenuation coefficients of polymer bearings simultaneously. • The method has a thickness identification error of approximately 0.5% for PEEK specimens with different probe contact pressure, roughness, and tilt angle, and the reconfiguration thickness identification error is less than 1% for the full range of water film overlap. [ABSTRACT FROM AUTHOR]