Background. Whether carotid tortuosity/kinking of the internal carotid artery leads to cerebral ischemia remains unclear. There is very little research about the hemodynamic variation induced by carotid tortuosity/kinking in the literature. The objective of this study was to research the blood pressure changes induced by carotid tortuosity/kinking. Methods. We first created a geometric model of carotid tortuosity/kinking. Based on hemodynamic boundary conditions, the hemodynamics of carotid tortuosity and kinking were studied via a finite element simulation. Then, an in vitro system was built to validate the numerical simulation results. The mean arterial pressure changes before and after carotid kinking were measured using pressure sensors in 12 patients with carotid kinking. Results. Numerical simulation revealed that the pressure drops increased with increases in the kinking angles. Clinical tests and in vitro experiments confirmed the numerical simulation results. Conclusions. Carotid kinking leads to blood pressure reduction. In certain conditions, kinking may affect the cerebral blood supply and be associated with cerebral ischemia.

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At present, diseases resulting from various reasons have been causing deadly fears to humans and previously incogitable losses to health. Meanwhile, the patient compliance has been weakening because of drug resistance and serious drug adverse effects. There is therefore an urgent need for the development of novel structural agents. Rhodanine derivatives have exhibited wide biological activities, as well as significant industrial applications, which suggests that rhodanine heterocycle represents a key structural motif in heterocyclic chemistry and occupies a prominent position in drug discovery. Here, we review some deadly defects of clinical medicines to the therapy of diseases and important advances on rhodanine derivatives in drug researches (e.g. as anti-diabetic, anti-viral, antiinflammatory, anti-microbial, anti-tumor agents and inhibitors for Alzheimer Disease), indicating that rhodanine heterocycle could be used as a significant pharmacophore to develop novel pharmacological active molecules. It is believed that the review is of importance for new ideas in the development of and rational designs of rhodanine-based drugs.

The exploitation of functional phosphors possessing a variety of advantages including narrow-band emission, fast response to near-ultraviolet (n-UV)/blue light excitation, high quantum efficiency, and low thermal quenching, will be essentially...

The maximum upsurge (MU) and the maximum air chamber pressure (MACP) are critical parameters for the design of air cushion surge chamber (ACSC) in hydropower stations. In this paper, the existence of the MU and the MACP are proved under compound conditions. The theoretical formula predicting the most dangerous superposition moment of the MU and the MACP under compound condition is derived, and the influence factors are analyzed as well. To verify the accuracy of the formula, the rigid model based on Runge-Kutta method (RKM) and the elastic model based on the method of characteristics (MOC) are established, respectively, according to the parameters of the ACSC system in the practical hydropower station. The numerical results agree well with the theoretical predictions. In addition, the MU and the MACP under three control conditions are simulated, respectively, and the results show that when the cross-sectional area of throttled orifice is small, the MU and the MACP occur under the successive load rejection condition (SLR); when the cross-sectional area is large, the MU and the MACP occur under the load rejection after load acceptance condition (LRLA).